Radio

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General

See also Audio streams, Streaming, Electronics, Wi-Fi

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  • https://en.wikipedia.org/wiki/Intentional_radiator - any device that is deliberately designed to produce radio waves.Radio transmitters of all kinds, including the garage door opener, cordless telephone, cellular phone, wireless video sender, wireless microphone, and many others fall into this category.



  • https://en.wikipedia.org/wiki/Smith_chart - invented by Phillip H. Smith (1905–1987), is a graphical aid or nomogram designed for electrical and electronics engineers specializing in radio frequency (RF) engineering to assist in solving problems with transmission lines and matching circuits. The Smith chart can be used to simultaneously display multiple parameters including impedances, admittances, reflection coefficients, scattering parameters, noise figure circles, constant gain contours and regions for unconditional stability, including mechanical vibrations analysis. The Smith chart is most frequently used at or within the unity radius region. However, the remainder is still mathematically relevant, being used, for example, in oscillator design and stability analysis. While the use of paper Smith charts for solving the complex mathematics involved in matching problems has been largely replaced by software based methods, the Smith charts display is still the preferred method of displaying how RF parameters behave at one or more frequencies, an alternative to using tabular information. Thus most RF circuit analysis software includes a Smith chart option for the display of results and all but the simplest impedance measuring instruments can display measured results on a Smith chart display.


Broadcasting




  • https://en.wikipedia.org/wiki/Wireless_communication - or sometimes simply wireless, is the transfer of information or power between two or more points that are not connected by an electrical conductor. The most common wireless technologies use radio waves. With radio waves distances can be short, such as a few meters for Bluetooth or as far as millions of kilometers for deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples of applications of radio wireless technology include GPS units, garage door openers, wireless computer mice, keyboards and headsets, headphones, radio receivers, satellite television, broadcast television and cordless telephones.

Somewhat less common methods of achieving wireless communications include the use of other electromagnetic wireless technologies, such as light, magnetic, ...used from about 1890 for the first radio transmitting and receiving technology, as in wireless telegraphy, until the new word radio replaced it around 1920. The term was revived in the 1980s and 1990s mainly to distinguish digital devices that communicate without wires, such as the examples listed in the previous paragraph, from those that require wires or cables. This became its primary usage in the 2000s, due to the advent of technologies such as LTE, LTE-Advanced, Wi-Fi and Bluetooth.

Wireless operations permit services, such as long-range communications, that are impossible or impractical to implement with the use of wires. The term is commonly used in the telecommunications industry to refer to telecommunications systems (e.g. radio transmitters and receivers, remote controls, etc.) which use some form of energy (e.g. radio waves, acoustic energy,) to transfer information without the use of wires. Information is transferred in this manner over both short and long distances.


  • https://en.wikipedia.org/wiki/Wireless_telegraphy - the transmission of telegraphy signals from one point to another by means of an electromagnetic, electrostatic or magnetic field, or by electrical current through the earth or water. The term is used synonymously for radio communication systems, also called radiotelegraphy, which transmit telegraph signals by radio waves. When the term originated in the late 19th century it also applied to other types of experimental wireless telegraph communication technologies, such as conduction and induction telegraphy. Radio telegraphy often used manually-sent Morse code; radioteletype (RTTY) always uses mechanically generated and recorded characters.




  • RadioDNS.uk - This site is a directory listing of the 500 radio stations in the United Kingdom which have RadioDNS Hybrid Radio services available. The list of frequencies, identifiers, multiplexes and transmitters is retrieved from the Ofcom Technical parameters. The service information is then fetched using the ETSI TS 102 818 Service and Programme Information standard (aka RadioEPG).



  • Part15 - License Free, legal, low-power radio broadcasting


  • https://en.wikipedia.org/wiki/Frequency_agility - the ability of a radar system to quickly shift its operating frequency to account for atmospheric effects, jamming, mutual interference with friendly sources, or to make it more difficult to locate the radar broadcaster through radio direction finding. The term can also be applied to other fields, including lasers or traditional radio transceivers using frequency-division multiplexing, but it remains most closely associated with the radar field and these other roles generally use the more generic term "frequency hopping".


Transmission

  • https://en.wikipedia.org/wiki/Transmitter - an electronic device which produces radio waves with an antenna. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating current, the antenna radiates radio waves.




  • https://en.wikipedia.org/wiki/Intermediate_frequency - a frequency to which a carrier wave is shifted as an intermediate step in transmission or reception. The intermediate frequency is created by mixing the carrier signal with a local oscillator signal in a process called heterodyning, resulting in a signal at the difference or beat frequency. Intermediate frequencies are used in superheterodyne radio receivers, in which an incoming signal is shifted to an IF for amplification before final detection is done.Conversion to an intermediate frequency is useful for several reasons. When several stages of filters are used, they can all be set to a fixed frequency, which makes them easier to build anreflectional receiverd to tune. Lower frequency transistors generally have higher gains so fewer stages are required. It's easier to make sharply selective filters at lower fixed frequencies.There may be several such stages of intermediate frequency in a superheterodyne receiver; two or three stages are called double (alternatively, dual) or triple conversion, respectively.




  • https://en.wikipedia.org/wiki/Link_budget - accounting of all of the gains and losses from the transmitter, through the medium (free space, cable, waveguide, fiber, etc.) to the receiver in a telecommunication system. It accounts for the attenuation of the transmitted signal due to propagation, as well as the antenna gains, feedline and miscellaneous losses. Randomly varying channel gains such as fading are taken into account by adding some margin depending on the anticipated severity of its effects. The amount of margin required can be reduced by the use of mitigating techniques such as antenna diversity or frequency hopping.

A simple link budget equation looks like this: Received Power (dB) = Transmitted Power (dB) + Gains (dB) − Losses (dB). Note that decibels are logarithmic measurements, so adding decibels is equivalent to multiplying the actual numeric ratios.


  • https://en.wikipedia.org/wiki/QRP_operation - refers to transmitting at reduced power while attempting to maximize one's effective range. The term QRP derives from the standard Q code used in radio communications, where "QRP" and "QRP?" are used to request, "Reduce power", and ask "Should I reduce power?" respectively. The opposite of QRP is QRO, or high-power operation.


  • https://en.wikipedia.org/wiki/RF_power_amplifier - a type of electronic amplifier that converts a low-power radio-frequency signal into a higher power signal. Typically, RF power amplifiers drive the antenna of a transmitter. Design goals often include gain, power output, bandwidth, power efficiency, linearity (low signal compression at rated output), input and output impedance matching, and heat dissipation.



Reception

  • https://en.wikipedia.org/wiki/Radio_receiver - an electronic device that receives radio waves and converts the information carried by them to a usable form. It is used with an antenna. The antenna intercepts radio waves (electromagnetic waves) and converts them to tiny alternating currents which are applied to the receiver, and the receiver extracts the desired information. The receiver uses electronic filters to separate the desired radio frequency signal from all the other signals picked up by the antenna, an electronic amplifier to increase the power of the signal for further processing, and finally recovers the desired information through demodulation.


  • https://en.wikipedia.org/wiki/Radio_receiver_design - includes the electronic design of different components of a radio receiver which processes the radio frequency signal from an antenna in order to produce usable information such as audio. The complexity of a modern receiver and the possible range of circuitry and methods employed are more generally covered in electronics and communications engineering. The term radio receiver is understood in this article to mean any device which is intended to receive a radio signal in order to generate useful information from the signal, most notably a recreation of the so-called baseband signal (such as audio) which modulated the radio signal at the time of transmission in a communications or broadcast system.



  • https://en.wikipedia.org/wiki/Regenerative_circuit - an amplifier circuit that employs positive feedback (also known as regeneration or reaction). Some of the output of the amplifying device is applied back to its input so as to add to the input signal, increasing the amplification. One example is the Schmitt trigger (which is also known as a regenerative comparator), but the most common use of the term is in RF amplifiers, and especially regenerative receivers, to greatly increase the gain of a single amplifier stage.


  • https://en.wikipedia.org/wiki/Tuned_radio_frequency_receiver - or TRF receiver, is a type of radio receiver that is composed of one or more tuned radio frequency (RF) amplifier stages followed by a detector (demodulator) circuit to extract the audio signal and usually an audio frequency amplifier. This type of receiver was popular in the 1920s. Early examples could be tedious to operate because when tuning in a station each stage had to be individually adjusted to the station's frequency, but later models had ganged tuning, the tuning mechanisms of all stages being linked together, and operated by just one control knob. By the mid 1930s, it was replaced by the superheterodyne receiver patented by Edwin Armstrong.


  • https://en.wikipedia.org/wiki/Reflex_receiver - occasionally called a reflectional receiver, is a radio receiver design in which the same amplifier is used to amplify the high-frequency radio signal (RF) and low-frequency audio (sound) signal (AF). It was first invented in 1914 by German scientists Wilhelm Schloemilch and Otto von Bronk, and rediscovered and extended to multiple tubes in 1917 by Marius Latour and William H. Priess. The radio signal from the antenna and tuned circuit passes through an amplifier, is demodulated in a detector which extracts the audio signal from the radio carrier, and the resulting audio signal passes again through the same amplifier for audio amplification before being applied to the earphone or loudspeaker. The reason for using the amplifier for "double duty" was to reduce the number of active devices, vacuum tubes or transistors, required in the circuit, to reduce the cost. The economical reflex circuit was used in inexpensive vacuum tube radios in the 1920s, and was revived again in simple portable tube radios in the 1930s.




  • https://en.wikipedia.org/wiki/Superheterodyne_receiver - often shortened to superhet, is a type of radio receiver that uses frequency mixing to convert a received signal to a fixed intermediate frequency (IF) which can be more conveniently processed than the original carrier frequency. It was invented by US engineer Edwin Armstrong in 1918 during World War I. Virtually all modern radio receivers use the superheterodyne principle.


  • https://en.wikipedia.org/wiki/Frequency_mixer - a nonlinear electrical circuit that creates new frequencies from two signals applied to it. In its most common application, two signals are applied to a mixer, and it produces new signals at the sum and difference of the original frequencies. Other frequency components may also be produced in a practical frequency mixer.
  • https://en.wikipedia.org/wiki/Heterodyne - a signal processing technique invented by Canadian inventor-engineer Reginald Fessenden that creates new frequencies by combining or mixing two frequencies. Heterodyning is used to shift one frequency range into another, new one, and is also involved in the processes of modulation and demodulation. The two frequencies are combined in a nonlinear signal-processing device such as a vacuum tube, transistor, or diode, usually called a mixer.



  • https://en.wikipedia.org/wiki/Direct-conversion_receiver - also known as homodyne, synchrodyne, or zero-IF receiver, is a radio receiver design that demodulates the incoming radio signal using synchronous detection driven by a local oscillator whose frequency is identical to, or very close to the carrier frequency of the intended signal. This is in contrast to the standard superheterodyne receiver where this is accomplished only after an initial conversion to an intermediate frequency. The simplification of performing only a single frequency conversion reduces the basic circuit complexity but other issues arise, for instance, regarding dynamic range and image rejection. In its original form it was unsuited to receiving AM and FM signals without implementing an elaborate phase locked loop. Although these and other technical challenges made this technique rather impractical around the time of its invention (1930's), current technology, and software radio in particular, have revived its use in certain areas including some consumer products.


Two-way


  • https://en.wikipedia.org/wiki/Air_interface - or access mode, is the communication link between the two stations in mobile or wireless communication. The air interface involves both the physical and data link layers (layer 1 and 2) of the OSI model for a connection


  • https://en.wikipedia.org/wiki/Duplex_(telecommunications) - a point-to-point system composed of two or more connected parties or devices that can communicate with one another in both directions. Duplex systems are employed in many communications networks, either to allow for simultaneous communication in both directions between two connected parties or to provide a reverse path for the monitoring and remote adjustment of equipment in the field. There are two types of duplex communication systems: full-duplex (FDX) and half-duplex (HDX).


  • https://en.wikipedia.org/wiki/Selective_calling - used to address a subset of all two-way radios on a single radio frequency channel. Where more than one user is on the same channel, (co-channel users,) selective calling can address a subset of all receivers or can direct a call to a single radio. Selective calling features fit into two major categories — individual calling and group calling. Individual calls generally have longer time-constants: it takes more air-time to call an individual radio unit than to call a large group of radios.Selective calling is akin to the use of a lock on a door. A radio with carrier squelch is unlocked and will let any signal in. Selective calling locks out all signals except ones with the correct "key", in this case a specific digital code. Selective calling systems can overlap; a radio may have (group call) and DTMF individual calling.


  • https://en.wikipedia.org/wiki/Call_sign - also known as a call name' or call letters, historically as a call signal, or abbreviated as a call, is a unique designation for a transmitter station. In North America, they are used for all FCC-licensed transmitters. A call sign can be formally assigned by a government agency, informally adopted by individuals or organizations, or even cryptographically encoded to disguise a station's identity. The use of call signs as unique identifiers dates to the landline railroad telegraph system. Because there was only one telegraph line linking all railroad stations, there needed to be a way to address each one when sending a telegram. In order to save time, two-letter identifiers were adopted for this purpose. This pattern continued in radiotelegraph operation; radio companies initially assigned two-letter identifiers to coastal stations and stations aboard ships at sea. These were not globally unique, so a one-letter company identifier (for instance, 'M' and two letters as a Marconi station) was later added. By 1912, the need to quickly identify stations operated by multiple companies in multiple nations required an international standard; an ITU prefix would be used to identify a country, and the rest of the call sign an individual station in that country.



  • https://en.wikipedia.org/wiki/AN/TRC-97 - a radio set that has 12 multiplex channels (later expanded to 24 channels and 16 telegraph channels connected to an analog radio. The radio set is a mobile terminal that can transmit up to 40 miles (64 km) straight line-of-sight at up to 1 watt, using a traveling wave tube amplifier, or 96 miles (154 km) in tropospheric scatter at up to 1 kilowatt, using a tunable klystron amplifier, at a frequency range of 4.4 to 5 gigahertz and 1.2 to 2.2 gigahertz.


Spectrum

  • https://en.wikipedia.org/wiki/Radio_spectrum - the part of the electromagnetic spectrum from 3 Hz to 3000 GHz (3 THz). Electromagnetic waves in this frequency range, called radio waves, are extremely widely used in modern technology, particularly in telecommunication. To prevent interference between different users, the generation and transmission of radio waves is strictly regulated by national laws, coordinated by an international body, the International Telecommunication Union (ITU).

Different parts of the radio spectrum are appointed by the ITU for different radio transmission technologies and applications; some 40 radiocommunication services are defined in the ITU's Radio Regulations (RR). In some cases, parts of the radio spectrum are sold or licensed to operators of private radio transmission services (for example, cellular telephone operators or broadcast television stations). Ranges of allocated frequencies are often referred to by their provisioned use (for example, cellular spectrum or television spectrum).


  • https://en.wikipedia.org/wiki/Extremely_low_frequency - electromagnetic radiation (radio waves) with frequencies from 3 to 30 Hz, and corresponding wavelengths of 100,000 to 10,000 kilometers, respectively. In atmospheric science, an alternative definition is usually given, from 3 Hz to 3 kHz. In the related magnetosphere science, the lower frequency electromagnetic oscillations (pulsations occurring below ~3 Hz) are considered to lie in the ULF range, which is thus also defined differently from the ITU radio bands.

ELF radio waves are generated by lightning and natural disturbances in Earth's magnetic field, so they are a subject of research by atmospheric scientists. Because of the difficulty of building antennas that can radiate such long waves, ELF frequencies have been used in only a very few human-made communication systems. ELF waves can penetrate seawater, which makes them useful in communication with submarines. The US, Russia, and India are the only nations known to have constructed ELF communication facilities. The U.S. facilities were used between 1985 and 2004 but are now decommissioned. ELF waves can also penetrate significant distances into earth or rock, and "through-the-earth" underground mine communication systems use frequencies of 300 to 3000 Hz. The frequency of alternating current flowing in electric power grids, 50 or 60 Hz, also falls within the ELF band, making power grids an unintentional source of ELF radiation.


  • https://en.wikipedia.org/wiki/Super_low_frequency - frequency range between 30 hertz and 300 hertz. They have corresponding wavelengths of 10,000 to 1,000 kilometers. This frequency range includes the frequencies of AC power grids (50 hertz and 60 hertz). Another conflicting designation which includes this frequency range is Extremely Low Frequency (ELF), which in some contexts refers to all frequencies up to 300 hertz.


  • https://en.wikipedia.org/wiki/Ultra_low_frequency - frequency range of electromagnetic waves between 300 hertz and 3 kilohertz. In magnetosphere science and seismology, alternative definitions are usually given, including ranges from 1 mHz to 100 Hz, 1 mHz to 1 Hz, 10 mHz to 10 Hz. Frequencies above 3 Hz in atmosphere science are usually assigned to the ELF range.



  • https://en.wikipedia.org/wiki/Low_frequency - LF is the ITU designation for radio frequencies (RF) in the range of 30 kHz–300 kHz. As its wavelengths range from ten kilometres to one kilometre, respectively, it is also known as the kilometre band or kilometre wave. LF radio waves exhibit low signal attenuation, making them suitable for long-distance communications. In Europe and areas of Northern Africa and Asia, part of the LF spectrum is used for AM broadcasting as the "longwave" band. In the western hemisphere, its main use is for aircraft beacon, navigation (LORAN), information, and weather systems. A number of time signal broadcasts are also broadcast in this band.
  • https://en.wikipedia.org/wiki/Longwave - also written as long wave (in British and American parlance) or long-wave, and commonly abbreviated LW, refers to parts of the radio spectrum with relatively long wavelengths. The term is an historic one, dating from the early 20th century, when the radio spectrum was considered to consist of long (LW), medium (MW) and short (SW) radio wavelengths. Most modern radio systems and devices use wavelengths which would then have been considered 'ultra-short'.

In contemporary usage, the term longwave is not defined precisely, and its meaning varies across the world. Most commonly, it refers to radio wavelengths longer than 1000 metres; frequencies less than 300 kilohertz (kHz), including the International Telecommunications Union's (ITU's) low frequency (LF) (30–300 kHz) and very low frequency (VLF) (3–30 kHz) bands. Sometimes, part of the medium frequency (MF) band (300–3000 kHz) is included.


  • https://en.wikipedia.org/wiki/Medium_wave - the part of the medium frequency (MF) radio band used mainly for AM radio broadcasting. For Europe the MW band ranges from 526.5 kHz to 1606.5 kHz, using channels spaced every 9 kHz, and in North America an extended MW broadcast band goes from 535 kHz to 1705 kHz, using 10 kHz spaced channels.


Radio waves in this band can be reflected or refracted from a layer of electrically charged atoms in the atmosphere called the ionosphere. Therefore short waves directed at an angle into the sky can be reflected back to Earth at great distances, beyond the horizon. This is called skywave or skip propagation. Thus shortwave radio can be used for very long distance communication, in contrast to radio waves of higher frequency which travel in straight lines (line-of-sight propagation) and are limited by the visual horizon, about 40 miles. Shortwave radio is used for broadcasting of voice and music to shortwave listeners over very large areas; sometimes entire continents or beyond. It is also used for military over-the-horizon radar, diplomatic communication, and two-way international communication by amateur radio enthusiasts for hobby, educational and emergency purposes.






  • https://en.wikipedia.org/wiki/Microwave - with wavelengths ranging from one meter to one millimeter; with frequencies between 300 MHz (100 cm) and 300 GHz (0.1 cm). This broad definition includes both UHF and EHF (millimeter waves), and various sources use different boundaries. In all cases, microwave includes the entire SHF band (3 to 30 GHz, or 10 to 1 cm) at minimum, with RF engineering often restricting the range between 1 and 100 GHz (300 and 3 mm).

The prefix micro- in microwave is not meant to suggest a wavelength in the micrometer range. It indicates that microwaves are "small", compared to waves used in typical radio broadcasting, in that they have shorter wavelengths. The boundaries between far infrared, terahertz radiation, microwaves, and ultra-high-frequency radio waves are fairly arbitrary and are used variously between different fields of study.


  • https://en.wikipedia.org/wiki/Extremely_high_frequency - EHF, from 30 to 300 gigahertz. It lies between the super high frequency band, and the far infrared band which is also referred to as the terahertz gap. Radio waves in this band have wavelengths from ten to one millimetre, giving it the name millimetre band or millimetre wave, sometimes abbreviated MMW or mmW. Millimetre-length electromagnetic waves were first investigated in the 1890s by Indian scientist Jagadish Chandra Bose.


  • https://en.wikipedia.org/wiki/Terahertz_radiation - also known as submillimeter radiation, terahertz waves, tremendously high frequency, T-rays, T-waves, T-light, T-lux or THz – consists of electromagnetic waves within the ITU-designated band of frequencies from 0.3 to 3 terahertz (THz; 1 THz = 1012 Hz). Wavelengths of radiation in the terahertz band correspondingly range from 1 mm to 0.1 mm (or 100 μm). Because terahertz radiation begins at a wavelength of one millimeter and proceeds into shorter wavelengths, it is sometimes known as the submillimeter band, and its radiation as submillimeter waves, especially in astronomy.

Terahertz radiation occupies a middle ground between microwaves and infrared light waves known as the terahertz gap, where technology for its generation and manipulation is in its infancy. It represents the region in the electromagnetic spectrum where the frequency of electromagnetic radiation becomes too high to be measured digitally via electronic counters, so must be measured by proxy using the properties of wavelength and energy. Similarly, the generation and modulation of coherent electromagnetic signals in this frequency range ceases to be possible by the conventional electronic devices used to generate radio waves and microwaves, requiring the development of new devices and techniques. Photon energy in THz regime is less than band-gap of nonmetallic materials and thus THz beam can traverse through such materials. The transmitted THz beam is used for material characterization, layer inspection and developing transmission images.


  • https://en.wikipedia.org/wiki/Terahertz_gap - an engineering term for a band of frequencies in the terahertz region of the electromagnetic spectrum between radio waves and infrared light for which practical technologies for generating and detecting the radiation do not exist. It is defined as 0.1 to 10 THz (wavelengths of 3 mm to 30 µm). Currently, at frequencies within this range, useful power generation and receiver technologies are inefficient and impractical.


  • https://en.wikipedia.org/wiki/Far_infrared - often defined as any radiation with a wavelength of 15 micrometers (µm) to 1 mm (corresponding to a range of about 20 THz to 300 GHz), which places far infrared radiation within the CIE IR-B and IR-C bands. Different sources use different boundaries for the far infrared spectrum; for example, astronomers sometimes define far infrared as wavelengths between 25 µm and 350 µm. Visible light includes radiation with wavelengths between 400 nm and 700 nm, meaning that far infrared photons have less energy than visible light photons.



Signals

  • http://www.sigidwiki.com/wiki/Signal_Identification_Guide - wiki intended to help identify radio signals through example sounds and waterfall images. Most signals are received and recorded using a software defined radio such as the RTL-SDR, Airspy, SDRPlay, HackRF, BladeRF, Funcube Dongle, USRP or others. [1]



Antenna




  • A.T.V - probably the most extensive aerials site on the Internet and in 2017 we had 370,000 visitors with 810,000 page hits. In fact even “the trade” use this site. Actually, even we use it if we want to check up on anything to do with aerials !



  • https://en.wikipedia.org/wiki/Antenna_feed - refers to several slightly different parts of an antenna system: The antenna feed is the wire or cabling (transmission line) that connects between the antenna and the radio, specifically called the feed line; The antenna feed is the location on the antenna where the feedline from the receiver or transmitter connects or attaches; The antenna feed is the matching system at the attachment point that converts the feedline impedance to the antenna’s intrinsic impedance, and makes any balanced-to-unbalanced conversion (if necessary).


  • https://en.wikipedia.org/wiki/Feed_horn - In parabolic antennas such as satellite dishes, a feed horn (or feedhorn) is a small horn antenna used to convey radio waves between the transmitter and/or receiver and the parabolic reflector. In transmitting antennas, it is connected to the transmitter and converts the radio frequency alternating current from the transmitter to radio waves and feeds them to the rest of the antenna, which focuses them into a beam. In receiving antennas, incoming radio waves are gathered and focused by the antenna's reflector on the feed horn, which converts them to a tiny radio frequency voltage which is amplified by the receiver. Feed horns are used mainly at microwave (SHF) and higher frequencies.



  • https://en.wikipedia.org/wiki/Hirose_U.FL - a miniature RF connector for high-frequency signals up to 6 GHz manufactured by Hirose Electric Group and others.U.FL connectors are commonly used in applications where space is of critical concern, most often Mini PCI cards for laptop computers. U.FL connectors are commonly used inside laptops and embedded systems to connect the Wi-Fi antenna to a Mini PCI card. Another common use is connecting GPS antennas.




Horn

  • https://en.wikipedia.org/wiki/Horn_antenna - or microwave horn is an antenna that consists of a flaring metal waveguide shaped like a horn to direct radio waves in a beam. Horns are widely used as antennas at UHF and microwave frequencies, above 300 MHz. They are used as feed antennas (called feed horns) for larger antenna structures such as parabolic antennas, as standard calibration antennas to measure the gain of other antennas, and as directive antennas for such devices as radar guns, automatic door openers, and microwave radiometers. Their advantages are moderate directivity, low standing wave ratio (SWR), broad bandwidth, and simple construction and adjustment.

Yagi

  • https://en.wikipedia.org/wiki/Yagi–Uda_antenna - ommonly known as a Yagi antenna, is a directional antenna consisting of multiple parallel elements in a line, usually half-wave dipoles made of metal rods. Yagi–Uda antennas consist of a single driven element connected to the transmitter or receiver with a transmission line, and additional "parasitic elements" which are not connected to the transmitter or receiver: a so-called reflector and one or more directors. It was invented in 1926 by Shintaro Uda of Tohoku Imperial University, Japan, and (with a lesser role played by his colleague) Hidetsugu Yagi. The reflector element is slightly longer than the driven dipole, whereas the directors are a little shorter.[4] The parasitic elements absorb and reradiate the radio waves from the driven element with a different phase, modifying the dipole's radiation pattern. The waves from the multiple elements superpose and interfere to enhance radiation in a single direction, achieving a very substantial increase in the antenna's gain compared to a simple dipole.Also called a "beam antenna",or "parasitic array", the Yagi is very widely used as a high-gain antenna on the HF, VHF and UHF bands. It has moderate to high gain which depends on the number of elements used, typically limited to about 20 dBi, linear polarization, unidirectional (end-fire) beam pattern with high front-to-back ratio of up to 20 db. and is lightweight, inexpensive and simple to construct. The bandwidth of a Yagi antenna, the frequency range over which it has high gain, is narrow, a few percent of the center frequency, and decreases with increasing gain, so it is often used in fixed-frequency applications. The largest and best-known use is as rooftop terrestrial television antennas, but it is also used for point-to-point fixed communication links, in radar antennas, and for long distance shortwave communication by shortwave broadcasting stations and radio amateurs.


  • Simple Wi-Fi Yagi - It's easy to make a small Yagi for a wireless router even if it lacks an antenna connector. The photo shows how I added two parasitic elements to the sleeve dipole of my Netgear WGR614. [5]


Loop

  • https://en.wikipedia.org/wiki/Loop_antenna - a radio antenna consisting of a loop or coil of wire, tubing, or other electrical conductor usually fed by a balanced source or feeding a balanced load. Within this physical description there are two distinct antenna types. The large self-resonant loop antenna has a circumference close to one wavelength of the operating frequency and so is resonant at that frequency. This category also includes smaller loops 5% to 30% of a wavelength in circumference, which use a capacitor to make them resonant. These antennas are used for both transmission and reception. In contrast, small loop antennas less than 1% of a wavelength in size are very inefficient radiators, and so are only used for reception. An example is the ferrite (loopstick) antenna used in most AM broadcast radios. Loop antennas have a dipole radiation pattern; they are most sensitive to radio waves in two broad lobes in opposite directions, 180° apart. Due to this directional pattern they are used for radio direction finding (RDF), to locate the position of a transmitter.

Evolved

  • https://en.wikipedia.org/wiki/Evolved_antenna - an antenna designed fully or substantially by an automatic computer design program that uses an evolutionary algorithm that mimics Darwinian evolution. This sophisticated procedure has been used in recent years to design a few antennas for mission-critical applications involving stringent, conflicting, or unusual design requirements, such as unusual radiation patterns, for which none of the many existing antenna types are adequate. [6]

Leaky feeder

  • https://en.wikipedia.org/wiki/Leaky_feeder - a communications system used in underground mining and other tunnel environments. Manufacturers and cabling professionals use the term "radiating cable" as this implies that the cable is designed to radiate: something that coaxial cable is not generally supposed to do.

to sort



Electronics

  • https://github.com/Open-RFlab/Open-RFlab - A free & open source, complete, powerful and user friendly platform to design RF electronics. A real alternative to proprietary and onerous softwares. That is the Open-RFlab project's goal.


  • RF Tools | LC Filter Design Tool - Calculate LC filters circuit values with low-pass, high-pass, band-pass, or band-stop response.Select Chebyshev, Elliptic, Butterworth or Bessel filter type, with filter order up to 20, and arbitrary input and output impedances.


RNode

  • RNode | unsigned.io - an open, free and unrestricted digital radio transceiver. It enables anyone to send and receive any kind of data over both short and very long distances. RNodes can be used with many different kinds of programs and systems, but they are especially well suited for use with the cryptographic networking stack Reticulum. RNode is not a product, and not any one specific device in particular. It is a system that is easy to replicate across space and time, that produces highly functional communications tools, which respects user autonomy and empowers individuals and communities to protect their sovereignty, privacy and ability to communicate and exchange data and ideas freely.


Modulation



  • https://en.wikipedia.org/wiki/Phase_detector - or phase comparator is a frequency mixer, analog multiplier or logic circuit that generates a signal which represents the difference in phase between two signal inputs. The phase detector is an essential element of the phase-locked loop (PLL). Detecting phase difference is important in other applications, such as motor control, radar and telecommunication systems, servo mechanisms, and demodulators.


  • https://en.wikipedia.org/wiki/Product_detector - a type of demodulator used for AM and SSB signals. Rather than converting the envelope of the signal into the decoded waveform like an envelope detector, the product detector takes the product of the modulated signal and a local oscillator, hence the name. A product detector is a frequency mixer. Product detectors can be designed to accept either IF or RF frequency inputs. A product detector which accepts an IF signal would be used as a demodulator block in a superheterodyne receiver, and a detector designed for RF can be combined with an RF amplifier and a low-pass filter into a direct-conversion receiver.


  • https://en.wikipedia.org/wiki/Costas_loop - a phase-locked loop (PLL, based circuit which is used for carrier frequency recovery from suppressed-carrier modulation signals (e.g. double-sideband suppressed carrier signals) and phase modulation signals (e.g. BPSK, QPSK). It was invented by John P. Costas at General Electric in the 1950s. Its invention was described as having had "a profound effect on modern digital communications". The primary application of Costas loops is in wireless receivers. Its advantage over other PLL-based detectors is that at small deviations the Costas loop error voltage is sin ⁡ ( 2 ( θ i − θ f ) ) as compared to sin ⁡ ( θ i − θ f ). This translates to double the sensitivity and also makes the Costas loop uniquely suited for tracking Doppler-shifted carriers, especially in OFDM and GPS receivers.




  • https://en.wikipedia.org/wiki/List_of_amateur_radio_modes - Amateurs use a variety of voice, text, image, and data communications modes over radio. Generally new modes can be tested in the amateur radio service, although national regulations may require disclosure of a new mode to permit radio licensing authorities to monitor the transmissions. Encryption, for example, is not generally permitted in the Amateur Radio service except for the special purpose of satellite vehicle control uplinks. The following is a partial list of the modes of communication used, where the mode includes both modulation types and operating protocols.


AM

AM radio ranges from 535 to 1705 kilohertz, stations are possible every 10 kHz.





FM

FM radio ranges in a higher spectrum from 88 to 108 megahertz, stations are possible every 200 kHz.




  • C. Crane FM2 Digital Full Spectrum FM Transmitter




  • https://en.wikipedia.org/wiki/MPX_filter - a function found in cassette decks. Residual high-frequency components of the signal remaining after de-multiplexing can be problematic when recording to analog magnetic media. While the higher frequencies are unlikely to survive filtering in the recording deck, the 19 kHz tone is within the 20 to 20,000 Hz frequency range for many tape formats, including compact cassette, and typically provides an audible beat (difference) tone in conjunction with the tape head bias signal used when recording. The recording may also be saturated by the pilot tone. More importantly, the pilot tone interferes with the proper functioning of noise reduction systems such as Dolby B, C and S. Because the pilot tone is relatively loud in comparison to the overall loudness of the FM program (typically -20dB), the source signal is not correctly processed by the noise reduction system, leading to audible artefacts such as breathing and pumping. For this reason many decks with defeatable MPX filters have been designed in such a way that the MPX filter can only be enabled when also a noise reduction system is enabled.


Digital



  • http://newton.i2lab.ucf.edu/wiki/Digital_modes - Signals sent by radio (or over long wires or when stored on magnetic media) must be modulated with some method that prevents their signal from degrading before the signals can be received. A transmitter and receiver must use the same mode of modulation to successfully communicate. A digital mode converts a signal with a finite set of discrete symbols (i.e., 1 and 0, or the alphabet) into a modulated signal suitable for transmission.


DAB

  • https://en.wikipedia.org/wiki/Digital_audio_broadcasting - DAB standard was initiated as a European research project in the 1980s. The Norwegian Broadcasting Corporation (NRK) launched the first DAB channel in the world on 1 June 1995 (NRK Klassisk), and the BBC and Swedish Radio (SR) launched their first DAB digital radio broadcasts in September 1995. DAB receivers have been available in many countries since the end of the 1990s.

Audio quality varies depending on the bitrate used and audio material. Most stations use a bit rate of 128 kbit/s or less with the MP2 audio codec, which requires 160 kbit/s to achieve perceived FM quality. 128 kbit/s gives better dynamic range or signal-to-noise ratio than FM radio, but a more smeared stereo image, and an upper cut-off frequency of 14 kHz, corresponding to 15 kHz of FM radio. However, "CD quality" sound with MP2 is possible "with 256…192 kbps".

An upgraded version of the system was released in February 2007, which is called DAB+. DAB is not forward compatible with DAB+, which means that DAB-only receivers are not able to receive DAB+ broadcasts. However, broadcasters can mix DAB and DAB+ programs inside the same transmission and so make a progressive transition to DAB+. DAB+ is approximately twice as efficient as DAB, and more robust.


HD Radio / NRSC-5



FMeXtra


ISDB


SDARS


DRM

  • https://en.wikipedia.org/wiki/Digital_Radio_Mondiale - DRM, a set of digital audio broadcasting technologies designed to work over the bands currently used for analogue radio broadcasting including AM broadcasting, particularly shortwave, and FM broadcasting. DRM is more spectrally efficient than AM and FM, allowing more stations, at higher quality, into a given amount of bandwidth, using various MPEG-4 audio coding formats.


  • Dream - Open-Source Software Implementation of a DRM (Digital Radio Mondiale) Receiver under the GNU General Public License (GPL).

CAM-D

  • https://en.wikipedia.org/wiki/CAM-D - Compatible Amplitude Modulation - Digital or CAM-D is a hybrid digital radio format for AM broadcasting, proposed by broadcast engineer Leonard R. Kahn.The system is an in-band on-channel technology that uses the sidebands of any AM radio station. Analog information is still used up to a bandpass of about 7.5kHz, with standard amplitude modulation. The missing treble information that AM normally lacks is then transmitted digitally beyond this. Audio mixing in the receiver then blends them back together.

Unlike other IBOC technologies like iBiquity's HD Radio, Kahn's apparently does not provide a direct path to all-digital transmissions, nor any multichannel capability. Its advantage, however, is that it takes up far less of the sidebands, thereby causing far less interference to adjacent channels, hence the "Compatible" in the name. Interference has affected HD Radio on AM, along with its (like CAM-D) proprietary nature.

Digital Radio Mondiale, commonly used in shortwave broadcasting, can use less, the same, or more bandwidth as AM, to provide high quality audio. Digital Radio Mondiale requires digital detection circuitry not present in conventional AM radios to decode programming.Special CAM-D receivers provide the benefit of better frequency response and a slow auxiliary data channel for display of station ID, programming titles, etc.

Trunked

  • https://en.wikipedia.org/wiki/Trunked_radio_system - two-way radio system that uses a control channel to automatically direct radio traffic. Two-way radio systems are either trunked or conventional, where conventional is manually directed by the radio user. Trunking is a more automated and complex radio system, but provides the benefits of less user intervention to operate the radio and greater spectral efficiency with large numbers of users. Instead of assigning, for example, a radio channel to one particular organization at a time, users are instead assigned to a logical grouping, a "talkgroup". When any user in that group wishes to converse with another user in the talkgroup, a vacant radio channel is found automatically by the system and the conversation takes place on that channel. Many unrelated conversations can occur on a channel, making use of the otherwise idle time between conversations. Each radio transceiver contains a microcomputer to control it. A control channel coordinates all the activity of the radios in the system. The control channel computer sends packets of data to enable one talkgroup to talk together, regardless of frequency.


  • https://github.com/robotastic/trunk-recorder - Trunk Recorder is able to record the calls on trunked and conventional radio systems. It uses 1 or more Software Defined Radios (SDRs) to do this. The SDRs capture large swatches of RF and then use software to process what was received. GNURadio is used to do this processing because it provides lots of convenient RF blocks that can be pieced together to allow for complex RF processing. The libraries from the amazing OP25 project are used for a lot of the P25 functionality. Multiple radio systems can be recorded at the same time.

AFSK

  • https://en.wikipedia.org/wiki/Frequency-shift_keying - a modulation technique by which digital data is represented by changes in the frequency (pitch) of an audio tone, yielding an encoded signal suitable for transmission via radio or telephone. Normally, the transmitted audio alternates between two tones: one, the "mark", represents a binary one; the other, the "space", represents a binary zero.

AFSK differs from regular frequency-shift keying in performing the modulation at baseband frequencies. In radio applications, the AFSK-modulated signal normally is being used to modulate an RF carrier (using a conventional technique, such as AM or FM) for transmission. AFSK is not always used for high-speed data communications, since it is far less efficient in both power and bandwidth than most other modulation modes. In addition to its simplicity, however, AFSK has the advantage that encoded signals will pass through AC-coupled links, including most equipment originally designed to carry music or speech. AFSK is used in the U.S.-based Emergency Alert System to notify stations of the type of emergency, locations affected, and the time of issue without actually hearing the text of the alert.


  • Not Black Magic: AFSK - is popular amongst Radio Amateurs and is used for the for the Automatic Packet Reporting System (APRS). It was also used in early telephone-line modems. Almost all AFSK modems these days follow the Bell 202 specification. Bell 202 enables a half-duplex communication at 1200 bit/s, using a mark tone (‘1’ bit) of 1200 Hz and a Space tone (‘0’ bit) of 2200 Hz. The basic set-up for AFSK transmission is shown in the block diagram bellow. PC TNC Radio Link Block Diagram When transmitting AFSK over a radio, like in a radio amateur set-up, the AFSK modulation is done by a TNC (terminal node controller). The TNC is also responsible for packet/frame assembly. The computer communicates the data to transmit to the TNC over a USB or a RS-232 interface. The TNC takes the raw data, assembles it into a frame, typically is a AX.25 frame, and encodes and modulates the frame into the audio band using AFSK. The resulting audio signal is then input into a Radio which in turn FM modulates the audio signal into the RF band, normally either VHF or UHF, which is transmitted over air. Reception is done in reverse order, the Radio demodulates the RF signal and feeds the resulting audio tone into the TNC which demodulates the audio signal, decodes the bits, de-assembles the packets and transmits the received data to the PC. This means that when AFSK is transmitted by a Radio the bits are double modulated, first in the Audio band by the TNC and then FM modulated into the RF band by the Radio, and can therefore be called a FM-AFSK modulation.




  • AFSK - SatNOGS Wiki - has a built-in demodulator for AFSK (Audio Frequency Shift Keying). Here's what a typical AFSK demod looks like. The (4) on the data tab shows that there are four demods available. Only two are shown here.


  • https://www.sigidwiki.com/wiki/AFSK_Paging_Link - POCSAG and FLEX are read as pulse trains in FM as their spectrum of FSK is only 2 carriers switching on and off. With this in mind, additional transmitters can use that pulse train waveform to be re-modulated as AFSK modes in an FM baseband ranging from Bell-202, Lojack, or any other modes as uplinks or downlinks in the RF bands.


  • https://github.com/markqvist/OpenModem - an open source firmware implementation of a AFSK modem supporting 300, 1200 and 2400 baud operation, suitable for communication over a wide variety of analogue mediums, both radio and wired. The firmware is designed for and compatible with unsigned.io's OpenModem, but can be used on any similar build. Complete modems are available from the unsigned.io shop, or can be build from scratch by referring to the schematics and documentation on the OpenModem page

Amateur / ham radio

  • https://en.wikipedia.org/wiki/Amateur_radio - also called ham radio, describes the use of radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communication. The term "amateur" is used to specify "a duly authorised person interested in radioelectric practice with a purely personal aim and without pecuniary interest;" (either direct monetary or other similar reward) and to differentiate it from commercial broadcasting, public safety (such as police and fire), or professional two-way radio services (such as maritime, aviation, taxis, etc.).

The amateur radio service (amateur service and amateur-satellite service) is established by the International Telecommunication Union (ITU) through the International Telecommunication Regulations. National governments regulate technical and operational characteristics of transmissions and issue individual stations licenses with an identifying call sign. Prospective amateur operators are tested for their understanding of key concepts in electronics and the host government's radio regulations. Radio amateurs use a variety of voice, text, image, and data communications modes and have access to frequency allocations throughout the RF spectrum to enable communication across a city, region, country, continent, the world, or even into space.





  • Amateur-radio-wiki - This site aims to enable ham operators and curious alike to document, share and explore the fantastic world of amateur radio.


  • ham-radio.com - site and it's hosted organizations offered as a free service to the Amateur Radio community.



  • SV2AGW - Quality Ham Software and Services.






  • Guerrilla Radio - How some inmates hack, rewire, and retool their radios to create walkie-talkies. [12]


  • https://en.wikipedia.org/wiki/Submillimeter_amateur_radio - refers to Amateur radio activity in the sub-millimeter region (275 GHz to 3 THz) of the electromagnetic spectrum. While no international frequency allocations exist for amateur radio in the sub-millimeter region, a number of administrations permit radio amateurs to experiment on Terahertz frequencies. Amateurs who operate in the region must design and construct their own equipment, and those who do, often attempt to set communication distance records on sub-millimeter frequencies.





Software

Fldigi

  • https://sourceforge.net/projects/fldigi - a modem program for most of the digital modes used by radio amateurs today: CW, PSK, MFSK, RTTY, Hell, DominoEX, Olivia, and Throb are all supported. It can help calibrate a sound card to a time signal and do frequency measurement tests.

FreeDV

  • FreeDV - Open Source Amateur Digital Voice, Where Amateur Radio Is Driving The State of the Art. A Digital Voice mode for HF radio. You can run FreeDV using a free GUI application for Windows, Linux and OSX that allows any SSB radio to be used for low bit rate digital voice. Alternatively you can buy a SM1000 FreeDV adaptor that allows you to run FreeDV on any HF radio without a PC or sound card. If you are a hardware or software developer, you can integrate FreeDV into your project using the LGPL licensed FreeDV API. Speech is compressed down to 700-1600 bit/s then modulated onto a 1.25 kHz wide signal comprised of 16 QPSK carriers which is sent to the Mic input of a SSB radio. The signal is received by an SSB radio, then demodulated and decoded by FreeDV. FreeDV 700C is approaching SSB in it’s low SNR performance. At high SNRs FreeDV 1600 sounds like FM, with no annoying analog HF radio noise. FreeDV was built by an international team of Radio Amateurs working together on coding, design, user interface and testing. FreeDV is open source software, released under the GNU Public License version 2.1. The modems and Codec 2 speech codec used in FreeDV are also open source.


xawtv radio

hfssdv


remoteAudio

  • https://github.com/dh1tw/remoteAudio - a cross plattform audio streaming application, built for Amateur Radio purposes. The most typical use case for this software is the remote operation of an amateur radio station. remoteAudio is written in Go.


HamWAN

  • HamWAN - a non-profit organization (501c3) developing best practices for high speed amateur radio data networks. HamWAN also runs the Puget Sound Data Ring, which is a real-world network implementation of the proposed designs.So far, HamWAN networks have been used for things like low-latency repeater linking, real-time video feeds from distant locations, serving APRS I-gates, providing redundant internet access to emergency operations centers, and more. Any licensed radio amateur in the service area can connect their shack directly to the network with just a small investment in equipment and no recurring cost. Since many traditional uses for Internet at home are not compatible with Part 97 rules, this won't replace your home Internet connection. However, it works and acts just like one.


Hot spots

DV Access Point Dongle

  • DV Access Point Dongle - connects to your PC or Intel based Mac via a USB port and provides a 2 meter Access Point for use with a D-STAR radio. Using an Internet connection, a user may connect to and communicate with D-STAR gateways and reflectors around the world. The DVAPTool application used with the DV Access Point Dongle may be installed and run on Microsoft Windows XP/Vista/7, Mac OS X Leopard/Snow Leopard, or many flavors of Linux.

DVAP

DV Dongle

  • DV Dongle - connects to your PC or Apple Mac via a USB port and provides encoding and decoding of compressed audio using the DVSI AMBE2000 full duplex vocoder DSP chip. AMBE technology is used in all D-Star radios to provide efficient voice transmissions. It is also used in some HF digital protocols by vendors like AOR. The DVTool application used with the DV Dongle may be installed and run on Microsoft Windows XP/Vista/7/8/10, Mac OS X, or many flavors of Linux.

DV4mini

DV MEGA

  • DV MEGA - The goal of the DV-MEGA project is to develop a KIT for a dual-band D-Star transceiver. Because this can't be done overnight different modules will be available all based on theD-Star stream. The D-Star steam is common to a DV-node adapter, radio hotspot and transceiver.

openSPOT2

JumboSPOT


pistar

  • pistar - a software image built initially for the Raspberry Pi (produced by the Raspberry Pi Foundation).The design concept is simple, provide the complex services and configuration for Digial Voice on Amateur radio in a way that makes it easily accessable to anyone just starting out, but make it configurable enough to be interesting for those of us who cant help but tinker.Pi-Star would not be here today, were it not for the software made by Jonathan Naylor (G4KLX), we started with his DStarRepeater and ircDDBGateway and now support the full G4KLX MMDVM suite, including the extra cross-mode gateways added on by Andy (CA6JAU), I cannot thank these guys for the vast amount of time and effort that they continue to put into their projects.Pi-Star can be what ever you want it to be, from a simple single mode hotsport running simplex providing you with access to the increasing number of Digital Voice networks, up to a public duplex multimode repeater!

to sort

TMRh20

Goals:

  • Extremely low-latency digital audio recording, playback, communication and relaying at high speeds

Features:

  • Now supports AVR devices (Arduino Uno,Nano,Mega,etc)
  • Designed with low-latency radio/wireless communication in mind
  • Very simple user interface to Arduino DUE DAC and ADC
  • PCM/WAV Audio/Analog Data playback using Arduino Due DAC
  • PCM/WAV Audio/Analog Data recording using Arduino Due ADC
  • Onboard timers drive the DAC & ADC automatically
  • Automatic sample rate/timer adjustment based on rate of user-driven data requests/input
  • Uses DMA (Direct Memory Access) to buffer DAC & ADC data
  • ADC & DAC: 8, 10 or 12-bit sampling
  • Single channel or stereo output
  • Multi-channel ADC sampling


RF24Audio

  • RF24Audio - Realtime Audio Streaming Library for Arduino. Audio Streaming Realtime with NRF24L01 radios. Realtime Audio Streaming Library for Arduino. This class implements a realtime audio streaming solution using nRF24L01(+) radios driven by the newly optimized RF24 library fork.

Radio control

See also RV

  • https://en.wikipedia.org/wiki/Radio_control - the use of radio signals to remotely control a device. Radio control is used for control of model vehicles from a hand-held radio transmitter. Industrial, military, and scientific research organizations make use of radio-controlled vehicles as well.



  • OpenSesame is a device that can wirelessly open virtually any fixed-code garage door in seconds, exploiting a new attack I've discovered on wireless fixed-pin devices. Using a child's toy from Mattel.

Satellite



  • https://en.wikipedia.org/wiki/AMSAT - a name for amateur radio satellite organizations worldwide, but in particular the Radio Amateur Satellite Corporation (AMSAT) with headquarters at Washington, D.C. AMSAT organizations design, build, arrange launches for, and then operate (command) satellites carrying amateur radio payloads, including the OSCAR series of satellites. Other informally affiliated national organizations exist, such as AMSAT Germany (AMSAT-DL) and AMSAT Japan (JAMSAT).


TV

See TV

Data

See also Signals, Data, Streaming



  • https://en.wikipedia.org/wiki/Datacasting - the broadcasting of data over a wide area via radio waves. It most often refers to supplemental information sent by television stations along with digital television, but may also be applied to digital signals on analog TV or radio. It generally does not apply to data which is inherent to the medium, such as PSIP data which defines virtual channels for DTV or direct broadcast satellite systems; or to things like cable modem or satellite modem, which use a completely separate channel for data.


Codes




  • https://en.wikipedia.org/wiki/Telegraph_key - a switching device used primarily to send Morse code. Similar keys are used for all forms of manual telegraphy, such as in ‘wire’ or electrical telegraph and ‘wireless’ or radio telegraphy.


  • https://en.wikipedia.org/wiki/Q_code a standardized collection of three-letter codes all of which start with the letter "Q". It is a brevity code initially developed for commercial radiotelegraph communication and later adopted by other radio services, especially amateur radio. To distinguish the use of "Q" codes transmitted as questions from those transmitted as statements, operators used the Morse question "INT" (dit dit dah dit dah) as a prefix to the "Q" code. Although Q codes were created when radio used Morse code exclusively, they continued to be employed after the introduction of voice transmissions. To avoid confusion, transmitter call signs are restricted; no country is ever issued an ITU prefix starting with "Q". Codes in the range QAA–QNZ are reserved for aeronautical use; QOA–QQZ for maritime use and QRA–QUZ for all services. "Q" has no official meaning, but it is sometimes assigned with a word with mnemonic value, such as "Queen's" (e.g. QFE = Queen's Field Elevation), "Query", "Question", or "reQuest".


Automatic Identification System

  • https://en.wikipedia.org/wiki/Automatic_identification_system - an automatic tracking system that uses transceivers on ships and is used by vessel traffic services (VTS). When satellites are used to receive AIS signatures, the term Satellite-AIS (S-AIS) is used. AIS information supplements marine radar, which continues to be the primary method of collision avoidance for water transport. Although technically and operationally distinct, the ADS-B system is analogous to AIS and performs a similar function for aircraft.


  • https://en.wikipedia.org/wiki/AIS-SART - a self-contained radio device used to locate a survival craft or distressed vessel by sending updated position reports using a standard Automatic Identification System (AIS) class-A position report. The position and time synchronization of the AIS-SART are derived from a built in GNSS receiver (e.g. GPS). Shipboard Global Maritime Distress Safety System (GMDSS) installations include one or more search and rescue locating devices. These devices may be either an AIS-SART (AIS Search and Rescue Transmitter) (from January 1, 2010), or a radar-SART (Search and Rescue Transponder).


ALE

  • https://en.wikipedia.org/wiki/Automatic_link_establishment - commonly known as ALE, is the worldwide de facto standard for digitally initiating and sustaining HF radio communications. ALE is a feature in an HF communications radio transceiver system that enables the radio station to make contact, or initiate a circuit, between itself and another HF radio station or network of stations. The purpose is to provide a reliable rapid method of calling and connecting during constantly changing HF ionospheric propagation, reception interference, and shared spectrum use of busy or congested HF channels.

ADS-B

  • https://en.wikipedia.org/wiki/Automatic_dependent_surveillance_%E2%80%93_broadcast - a surveillance technology in which an aircraft determines its position via satellite navigation and periodically broadcasts it, enabling it to be tracked. The information can be received by air traffic control ground stations as a replacement for secondary surveillance radar, as no interrogation signal is needed from the ground. It can also be received by other aircraft to provide situational awareness and allow self-separation. ADS–B is "automatic" in that it requires no pilot or external input. It is "dependent" in that it depends on data from the aircraft's navigation system.

APRS

  • https://en.wikipedia.org/wiki/Automatic_Packet_Reporting_System - an amateur radio-based system for real time digital communications of information of immediate value in the local area. Data can include object Global Positioning System (GPS) coordinates, weather station telemetry, text messages, announcements, queries, and other telemetry. APRS data can be displayed on a map, which can show stations, objects, tracks of moving objects, weather stations, search and rescue data, and direction finding data. In its most widely used form, APRS is transported over the AX.25 protocol using 1200 bit/s Bell 202 AFSK on frequencies located within the 2 meter amateur band.


  • aprs.fi map - The positions of the amateur radio operators and their vehicles are received from the APRS-IS network on the Internet. Most of them are originally transmitted on amateur radio frequencies (typically around 145 MHz), and received and forwarded to the APRS-IS by igate stations run by clubs and individuals around the world. The positions of ships are received from the AIS frequencies by receiving stations around the world. If you wish to receive AIS transmissions and provide them to the service, you're more than welcome to do so.



  • APRS-IS - the common name given to the Internet-based network which inter-connects various APRS radio networks throughout the world (and space). APRS-IS is maintained and operated by volunteer Amateur Radio operators to provide world-wide capabilities to the Amateur Radio APRS RF networks and to promote the Amateur Radio service as a whole.



  • https://github.com/markqvist/MicroAPRS - an APRS firmware for MicroModem. It supports both normal KISS mode, and a simple serial protocol for easy communication with an Arduino, or other MCU.


Radiosonde

  • https://en.wikipedia.org/wiki/Radiosonde - battery-powered telemetry instrument carried into the atmosphere usually by a weather balloon that measures various atmospheric parameters and transmits them by radio to a ground receiver. Modern radiosondes measure or calculate the following variables: altitude, pressure, temperature, relative humidity, wind (both wind speed and wind direction), cosmic ray readings at high altitude and geographical position (latitude/longitude). Radiosondes measuring ozone concentration are known as ozonesondes. Radiosondes may operate at a radio frequency of 403 MHz or 1680 MHz. A radiosonde whose position is tracked as it ascends to give wind speed and direction information is called a rawinsonde ("radar wind -sonde"). Most radiosondes have radar reflectors and are technically rawinsondes. A radiosonde that is dropped from an airplane and falls, rather than being carried by a balloon is called a dropsonde. Radiosondes are an essential source of meteorological data, and hundreds are launched all over the world daily.



WSPR

  • https://en.wikipedia.org/wiki/WSPR_(amateur_radio_software) - pronounced "whisper", stands for "Weak Signal Propagation Reporter". It is a protocol, implemented in a computer program, used for weak-signal radio communication between amateur radio operators. The protocol was designed, and a program written initially, by Joe Taylor, K1JT. Software is now open source and is developed by a small team. The program is designed for sending and receiving low-power transmissions to test propagation paths on the MF and HF bands.

WSPR implements a protocol designed for probing potential propagation paths with low-power transmissions. Transmissions carry a station's callsign, Maidenhead grid locator, and transmitter power in dBm. The program can decode signals with S/N as low as −28 dB in a 2500 Hz bandwidth. Stations with internet access can automatically upload their reception reports to a central database called WSPRnet, which includes a mapping facility.


  • WSPRnet - a group of amateur radio operators using K1JT's MEPT_JT digital mode to probe radio frequency propagation conditions using very low power (QRP/QRPp) transmissions. The software is open source, and the data collected are available to the public through this site.




  • https://github.com/threeme3/WsprryPi - Makes a very simple WSPR beacon from your RasberryPi by connecting GPIO port to Antanna (and LPF), operates on LF, MF, HF and VHF bands from 0 to 250 MHz.


LRPT

  • https://en.wikipedia.org/wiki/Low-rate_picture_transmission - LRPT, is a digital transmission system, intended to deliver images and data from an orbital weather satellite directly to end users via a VHF radio signal. It is used aboard polar-orbiting, near-Earth weather satellite programs such as MetOp and NPOESS.

RDS

  • https://en.wikipedia.org/wiki/Radio_Data_System - a communications protocol standard for embedding small amounts of digital information in conventional FM radio broadcasts. RDS standardizes several types of information transmitted, including time, station identification and program information.The standard began as a project of the European Broadcasting Union (EBU), but has since become an international standard of the International Electrotechnical Commission (IEC). Radio Broadcast Data System (RBDS) is the official name used for the U.S. version of RDS. The two standards are only slightly different.Both carry data at 1,187.5 bits per second on a 57 kHz subcarrier, so there are exactly 48 cycles of subcarrier during every data bit. The RBDS/RDS subcarrier was set to the third harmonic of the 19 kHz FM stereo pilot tone to minimize interference and intermodulation between the data signal, the stereo pilot and the 38 kHz DSB-SC stereo difference signal. (The stereo difference signal extends up to 38 kHz + 15 kHz = 53 kHz, leaving 4 kHz for the lower sideband of the RDS signal.) The data is sent with error correction. RDS defines many features including how private (in-house) or other undefined features can be "packaged" in unused program groups.



SCA / SCMO

Q15X25

  • https://en.wikipedia.org/wiki/Q15X25 - a communications protocol for sending data over a radio link. It was designed by amateur radio operator Pawel Jalocha, SP9VRC, to be an open communications standard. Like all amateur radio communications modes, this protocol uses open transmissions which can be received and decoded by anyone with similar equipment. Q15X25 is a form of packet radio. It can be used to interconnect local VHF AX.25 packet networks over transcontinental distances. Anyone can design or adapt the open-source software to develop their own Q15X25 system.

Radiofax

  • https://en.wikipedia.org/wiki/Radiofax - also known as weatherfax (portmanteau word from the words "weather facsimile") and HF fax (due to its common use on shortwave radio), is an analogue mode for transmitting monochrome images. It was the predecessor to slow-scan television (SSTV). Prior to the advent of the commercial telephone line "fax" machine, it was known, more traditionally, by the term "radiofacsimile". The cover of the regular NOAA publication on frequencies and schedules states "Worldwide Marine Radiofacsimile Broadcast Schedules".


Radioteletype

  • https://en.wikipedia.org/wiki/Radioteletype - a telecommunications system consisting originally of two or more electromechanical teleprinters in different locations connected by radio rather than a wired link. These machines were superseded by personal computers (PCs) running software to emulate teleprinters. Radioteletype evolved from earlier landline teleprinter operations that began in the mid-1800s. The US Navy Department successfully tested printing telegraphy between an airplane and ground radio station in 1922. Later that year, the Radio Corporation of America successfully tested printing telegraphy via their Chatham, Massachusetts, radio station to the R.M.S. Majestic. Commercial RTTY systems were in active service between San Francisco and Honolulu as early as April 1932 and between San Francisco and New York City by 1934. The US military used radioteletype in the 1930s and expanded this usage during World War II. From the 1980s, teleprinters were replaced by computers running teleprinter emulation software. The term radioteletype is used to describe both the original radioteletype system, sometimes described as "Baudot", as well as the entire family of systems connecting two or more teleprinters or PCs using software to emulate teleprinters, over radio, regardless of alphabet, link system or modulation.In some applications, notably military and government, radioteletype is known by the acronym RATT (Radio Automatic Teletype).



  • https://en.wikipedia.org/wiki/Phase-shift_keying - a digital modulation process which conveys data by changing (modulating) the phase of a constant frequency reference signal (the carrier wave). The modulation is accomplished by varying the sine and cosine inputs at a precise time. It is widely used for wireless LANs, RFID and Bluetooth communication.



  • bpsk31.com - a digital communication mode for amateur radio. It is one of the most common and easy-to-use digital modes as a PSK31 station needs only to consist of an SSB transceiver, an antenna, and a soundcard equipped PC.This website is a basic resource covering what is PSK31, how to set up and operate your own station, some available software, and additional resources.We also operate an email discussion list as a community resource where you can ask questions of other Hams and generally discuss anything related to PSK31.



  • https://en.wikipedia.org/wiki/PSK63 - meaning Phase Shift Keying at a rate of 63 baud) is a digital radio modulation mode used primarily in the amateur radio field to conduct real-time keyboard-to-keyboard informal text chat between amateur radio operators.


Packet radio

  • https://en.wikipedia.org/wiki/Packet_radio - the application of packet switching techniques to digital radio communications. Packet radio uses a packet switching protocol as opposed to circuit switching or message switching protocols to transmit digital data via a radio communication link. Packet radio is frequently used by amateur radio operators. The AX.25 (Amateur X.25) protocol was derived from the X.25 data link layer protocol and adapted for amateur radio use. Every AX.25 packet includes the sender's amateur radio callsign, which satisfies the US FCC requirements for amateur radio station identification. AX.25 allows other stations to automatically repeat packets to extend the range of transmissions. It is possible for any packet station to act as a digipeater, linking distant stations with each other through ad hoc networks. This makes packet radio especially useful for emergency communications.

Packet radio can be used in mobile communications. Some mobile packet radio stations transmit their location periodically using the Automatic Packet Reporting System (APRS). If the APRS packet is received by an "igate" station, position reports and other messages can be routed to an internet server, and made accessible on a public web page. This allows amateur radio operators to track the locations of vehicles, hikers, high-altitude balloons, etc., along with telemetry and other messages around the world. Some packet radio implementations also use dedicated point-to-point links such as TARPN. In cases such as this, new protocols have emerged such as Improved Layer 2 Protocol (IL2P) supporting forward error correction for noisy and weak signal links.



  • AGWPE - Sound Card Packet software
  • https://github.com/wb2osz/direwolf - a software "soundcard" AX.25 packet modem/TNC and APRS encoder/decoder. It can be used stand-alone to observe APRS traffic, as a tracker, digipeater, APRStt gateway, or Internet Gateway (IGate).



  • OpenModem - a very flexible and open packet radio modem and TNC. It is built on the proven reliability and performance of the MicroModem platform, but updated with all-round better components, a better DAC and ADC, a faster processor, and a much more powerful firmware, capable of many features that were simply not possible in the limited space of the previous iteration. New expansion ports for GPS, Bluetooth and SD cards have also been added. OpenModem supports both standard 1200-baud operation, but also 300-baud operation for HF packet, and experimental 2400-baud operation. OpenModem can handle large packets. With its MTU of 576 bytes and very large packet buffer, it can handle practically any packet radio software in existence. It also makes it possible to use the modem as a generic IP network interface in Linux.


  • DUAL - A New Packet Radio Link Control Layer - The standard amateur packet radio protocol, AX.25, provides the end-user with a virtual circuit interface to the link layer, while implementing this using packets, and using a CSMA medium access control mechanism. This paper suggests that the link layer in this application area should be separated into 3 layers (LLC, MAC and Physical Layer), and a set of modular protocols for each part be designed for amateur radio use. A new simplified Logical Link Control layer, DUAL, is described, which is not only more suitable than AX.25 for the transmission of higher-layer traffic, but also more bandwidth-efficient. This is achieved by using link layer addresses tailored to the network protocol used, minimizing the link layer overheads, and by incorporating a modified IP header compression scheme adapted for use in a multi-point environment.



ALOHAnet

  • https://en.wikipedia.org/wiki/ALOHAnet - also known as the ALOHA System, or simply ALOHA, was a pioneering computer networking system developed at the University of Hawaii. ALOHAnet became operational in June 1971, providing the first public demonstration of a wireless packet data network.

The ALOHAnet used a new method of medium access, called ALOHA random access, and experimental ultra high frequency (UHF) for its operation. In its simplest form, later known as Pure ALOHA, remote units communicated with a base station (Menehune) over two separate radio frequencies (for inbound and outbound respectively). Nodes did not wait for the channel to be clear before sending, but instead waited for acknowledgement of successful receipt of a message, and re-sent it if this was not received. Nodes would also stop and re-transmit data if they detected any other messages while transmitting. While simple to implement, this results in an efficiency of only 18.4%. A later advancement, Slotted ALOHA, improved the efficiency of the protocol by reducing the chance of collision, improving throughput to 36.8%.



TCP/IP

KA9Q
  • https://en.wikipedia.org/wiki/KA9Q - also called KA9Q NOS or simply NOS, was a popular early implementation of TCP/IP and associated protocols for amateur packet radio systems and smaller personal computers connected via serial lines. It was named after the amateur radio callsign of Phil Karn, who first wrote the software for a CP/M system and then ported it to DOS on the IBM PC. As the KA9Q package included source code, many radio amateurs modified it, so many different versions were available at the same time.


AX.25

  • https://en.wikipedia.org/wiki/AX.25 - a data link layer protocol originally derived from layer 2 of the X.25 protocol suite and designed for use by amateur radio operators. It is used extensively on amateur packet radio networks.AX.25 v2.0 and later occupies the data link layer, the second layer of the OSI model. It is responsible for establishing link-layer connections, transferring data encapsulated in frames between nodes, and detecting errors introduced by the communications channel. As AX.25 is a pre-OSI-model protocol, the original specification was not written to cleanly separate into OSI layers. This was rectified with version 2.0 (1984), which assumes compliance with OSI level 2.


  • https://en.wikipedia.org/wiki/Terminal_node_controller - a device used by amateur radio operators to participate in AX.25 packet radio networks. It is similar in function to the Packet Assembler/Disassemblers used on X.25 networks, with the addition of a modem to convert baseband digital signals to audio tones







  • https://en.wikipedia.org/wiki/Improved_Layer_2_Protocol - IL2P (Improved Layer 2 Protocol) is a data link layer protocol originally derived from layer 2 of the X.25 protocol suite and designed for use by amateur radio operators. It is used exclusively on amateur packet radio networks.

IL2P occupies the data link layer, the second layer of the OSI model. It is responsible for establishing link-layer connections, transferring data encapsulated in frames between nodes, and detecting errors introduced by the communications channel.

The Improved Layer 2 Protocol (IL2P) was created by Nino Carrillo, KK4HEJ, based on AX.25 version 2.0 and implements Reed Solomon Forward Error Correction for greater accuracy and throughput than either AX.25 or FX.25. Specifically, in order to achieve greater stability on link speeds higher than 1200 baud.

IL2P can be used with a variety of modulation methods including AFSK and GFSK. The direwolf software TNC contains the first open source implementation of the protocol.

IL2P

  • https://en.wikipedia.org/wiki/Improved_Layer_2_Protocol - IL2P, is a data link layer protocol originally derived from layer 2 of the X.25 protocol suite and designed for use by amateur radio operators. It is used exclusively on amateur packet radio networks. IL2P occupies the data link layer, the second layer of the OSI model. It is responsible for establishing link-layer connections, transferring data encapsulated in frames between nodes, and detecting errors introduced by the communications channel. The Improved Layer 2 Protocol (IL2P) was created by Nino Carrillo, KK4HEJ, based on AX.25 version 2.0 and implements Reed Solomon Forward Error Correction for greater accuracy and throughput than either AX.25 or FX.25. Specifically, in order to achieve greater stability on link speeds higher than 1200 baud. IL2P can be used with a variety of modulation methods including AFSK and GFSK. The direwolf software TNC contains the first open source implementation of the protocol.


KISS

  • KISS Protocol - The KISS ("Keep It Simple, Stupid") TNC provides direct computer to TNC communication using a simple protocol described here. Many TNCs now implement it, including the TAPR TNC-1 and TNC-2 (and their clones), the venerable VADCG TNC, the AEA PK-232/PK-87 and all TNCs in the Kantronics line. KISS has quickly become the protocol of choice for TCP/IP operation and multi-connect BBS software.


  • https://en.wikipedia.org/wiki/KISS_(amateur_radio_protocol) - a protocol for communicating with a serial terminal node controller (TNC) device used for amateur radio. This allows the TNC to combine more features into a single device and standardizes communications. KISS was developed by Mike Cheponis and Phil Karn to allow transmission of AX.25 packet radio frames containing IP packets over an asynchronous serial link, for use with the KA9Q NOS program. The KISS protocol is designed to be easy to implement in simple embedded devices, which are capable of asynchronous serial communications. While it allows arbitrary data to be transferred, there is no support for flow control or error handling.


  • PIC-Based TNC: What's a "Kiss Mode" TNC and Why Would I Want One? - When Packet Radio was getting underway in the late 1970s and early 1980s most people did not have very much computing power. Many hams (including me) wanted to operate packet with a Commodore 64, Vic 20, or CP/M computer that had a maximum of 64KB (yes, that KB, not MB or GB) of memory. There just wasn't much horsepower in those machines, but one thing that everyone had available was a terminal program. It was the lowest common denominator. So when designers developed TNC's in that era they designed them to work with anything that had a terminal emulator on it. As a result, they built nearly all of the intellegence in the TNC itself. Those TNC's had at least two modes. There was a "command mode" that allowed someone using a terminal program to set any of the dozens of parameters that were needed to optimize communications and it had a "converse mode" that packaged data and passed it to the radio to be transmitted. As time passed computers came along that were much more powerful. Many packet programs were developed that offered a lot more functionality and a more customized user interface. However, it was desirable to create a single interface that could be run on all TNC's that would look the same to the software program. At the same time, since computers had more processing power, it was possible to move some the data packaging functions from the TNC to the computer as well. There were a couple of different protocols developed for doing this, but the one that achieved the widest acceptance was "KISS" mode (for Keep it Simple Stupid). It was developed by Mike Chepponis and Phil Karn in 1987.



  • https://github.com/PA7FRN/kissTnc - a C++ implementation of the TNC software for Arduino. It can be used for AX.25 / packet radio as well as for APRS applications. It is tested on the Arduino Nano and is compatible with MicroAPRS and PA4RAZ APRS projects. The sketch and all used cpp and header files can be opened in the Arduino IDE.


  • https://github.com/markqvist/tncattach - Attach KISS TNC devices as network interfaces in Linux. This program allows you to attach TNCs or any KISS-compatible device as a network interface. This program does not need any kernel modules, and has no external dependencies outside the standard Linux and GNU C libraries.


AMPRNet

  • https://en.wikipedia.org/wiki/AMPRNet - AMateur Packet Radio Network) or Network 44 is used in amateur radio for packet radio and digital communications between computer networks managed by amateur radio operators. Like other amateur radio frequency allocations, an IP range of 44.0.0.0/8 was provided in 1981 for Amateur Radio Digital Communications (a generic term) and self-administered by radio amateurs. In 2001, undocumented and dual-use of 44.0.0.0/8 as a network telescope began, recording the spread of the Code Red II worm in July 2001.


D-STAR

  • https://en.wikipedia.org/wiki/D-STAR - a digital voice and data protocol specification for amateur radio. The system was developed in the late 1990s by the Japan Amateur Radio League and uses minimum-shift keying in its packet-based standard. There are other digital modes that have been adapted for use by amateurs, but D-STAR was the first that was designed specifically for amateur radio.

Several advantages of using digital voice modes are that it uses less bandwidth than older analog voice modes such as amplitude modulation and frequency modulation. The quality of the data received is also better than an analog signal at the same signal strength, as long as the signal is above a minimum threshold and as long as there is no multipath propagation. D-STAR compatible radios are available for HF, VHF, UHF, and microwave amateur radio bands. In addition to the over-the-air protocol, D-STAR also provides specifications for network connectivity, enabling D-STAR radios to be connected to the Internet or other networks, allowing streams of voice or packet data to be routed via amateur radio.



HSMM

  • https://en.wikipedia.org/wiki/High-speed_multimedia_radio - the implementation of high-speed wireless TCP/IP data networks over amateur radio frequency allocations using commercial off-the-shelf (COTS) hardware such as 802.11 Wi-Fi access points. This is possible because the 802.11 unlicensed frequency bands partially overlap with amateur radio bands and ISM bands in many countries. Only licensed amateur radio operators may legally use amplifiers and high-gain antennas within amateur radio frequencies to increase the power and coverage of an 802.11 signal.




AREDN

  • Amateur Radio Emergency Data Network - provides a way for Amateur Radio operators to create high-speed ad hoc Data Networks for use in Emergency and service-oriented communications. The primary goal of the AREDN® project, which is to empower licensed amateur radio operators to quickly and easily deploy high-speed data networks when and where they are needed, as a service both to the hobby and the community. This is especially important in cases when traditional “utility” services (electricity, phone lines, or Internet services) become unavailable. In those cases an off-grid amateur radio emergency data network may be a lifeline for communities impacted by a local disaster.


New Packet Radio

  • NPR New Packet Radio | Hackaday.io - a custom radio protocol, designed to transport bidirectional IP trafic over 430MHz radio links (ham radio frequencies 420-450MHz). This protocol is optimized for "point to multipoint" topology, with the help of managed-TDMA. Bitrate is 50 to 500kbps (net, effective bitrate), depending on the RF bandwidth chosen. The radio modem is cheap (~80$) and home-made, with a 433MHz ISM module inside (flexible enough to be tuned over the whole 420-450MHz band). The modem is connected locally with Ethernet, therefore no specific software is needed on PC. The modem is easy to build and reproduce. You can add a DMR radio amplifier in order to achieve 20W radio power or more. The main usage is an extension of HSMM - Hamnet - AREDN networks. [18]

M17

  • M17 Project - a community of open source developers and radio enthusiasts. We're building understandable systems in support of the hackers and experimenters' history of ham radio. Donate Get Started Read the Spec Open Source Digital Radio Our Current Goal /user/pages/01.home/02._our-current-goal/m17glow.png M17 is developing a new digital radio protocol for data and voice, made by and for amateur radio operators. Our protocol's voice mode uses the free and open Codec 2 voice encoder. This means there are no patents, no royalties, and no licensing or legal barriers to scratch-building your own radio or modifying one you already own. This freedom to build, understand, and innovate is core to amateur radio, but has been missing from the commercially available digital voice modes. This is part of why amateur radio digital voice modes have largely stagnated since the 1990s and we're almost wholly dependent on commercial products that aren't well designed for amateur radio users. M17 is about unlocking the capabilities that amateur radio hardware should already have. Here you will find people working on radio hardware designs that can be copied and built by anyone, software that anyone has the freedom to modify and share to suit their own needs, and other open systems that respect your freedom to tinker. [19]


Winlink

  • Winlink Global Radio Email - a network of amateur radio and authorized government stations that provide worldwide radio email using radio pathways where the internet is not present. The system is built, operated and administered entirely by licensed "Ham" volunteers. It supports email with attachments, position reporting, weather and information bulletins, and is well-known for its role in interoperable emergency and disaster relief communications. It is capable of operating completely without the internet--automatically--using smart-network radio relays. Licensed Winlink operators/stations use both amateur radio and government radio frequencies worldwide. Support for the system is provided by the Amateur Radio Safety Foundation, Inc., a US 501(c)(3) non-profit, public-benefit entity. Winlink Global Radio Email®️ is a US registered trademark of the Amateur Radio Safety Foundation, Inc.


LoRa

  • https://en.wikipedia.org/wiki/LoRa - a patented digital wireless data communication IoT technology developed by Cycleo of Grenoble, France, and acquired by Semtech in 2012. LoRa uses license-free sub-gigahertz radio frequency bands like 169 MHz, 433 MHz, 868 MHz (Europe) and 915 MHz (North America). LoRa enables very-long-range transmissions (more than 10 km in rural areas) with low power consumption. The technology is presented in two parts — LoRa, the physical layer and LoRaWAN, the upper layers.







Bluetooth

See Bluetooth

Mobile phone





  • https://en.wikipedia.org/wiki/Base_transceiver_station - a piece of equipment that facilitates wireless communication between user equipment (UE) and a network. UEs are devices like mobile phones (handsets), WLL phones, computers with wireless Internet connectivity, or antennas mounted on buildings or telecommunication towers. The network can be that of any of the wireless communication technologies like GSM, CDMA, wireless local loop, Wi-Fi, WiMAX or other wide area network (WAN) technology. BTS is also referred to as the node B (in 3G networks) or, simply, the base station (BS). For discussion of the LTE standard the abbreviation eNB for evolved node B is widely used, and GNodeB for 5G.

Though the term BTS can be applicable to any of the wireless communication standards, it is generally associated with mobile communication technologies like GSM and CDMA. In this regard, a BTS forms part of the base station subsystem (BSS) developments for system management. It may also have equipment for encrypting and decrypting communications, spectrum filtering tools (band pass filters) and so on. Antennas may also be considered as components of BTS in general sense as they facilitate the functioning of BTS. Typically a BTS will have several transceivers (TRXs) which allow it to serve several different frequencies and different sectors of the cell (in the case of sectorised base stations). A BTS is controlled by a parent base station controller via the base station control function (BCF). The BCF is implemented as a discrete unit or even incorporated in a TRX in compact base stations. The BCF provides an operations and maintenance (O&M) connection to the network management system (NMS), and manages operational states of each TRX, as well as software handling and alarm collection. The basic structure and functions of the BTS remains the same regardless of the wireless technologies.



1G

  • https://en.wikipedia.org/wiki/1G - refers to the first generation of wireless cellular technology (mobile telecommunications). These are the analog telecommunications standards that were introduced in the 1980s and continued until being replaced by 2G digital telecommunications. The main difference between the two mobile cellular systems (1G and 2G), is that the radio signals used by 1G networks are analog, while 2G networks are digital.

2G

  • https://en.wikipedia.org/wiki/2G - short for second-generation cellular technology. Second-generation 2G cellular networks were commercially launched on the GSM standard in Finland by Radiolinja (now part of Elisa Oyj) in 1991. Three primary benefits of 2G networks over their predecessors were that phone conversations were digitally encrypted; 2G systems were significantly more efficient on the spectrum allowing for far greater wireless penetration levels; and 2G introduced data services for mobile, starting with SMS text messages. 2G technologies enabled the various networks to provide the services such as text messages, picture messages, and MMS (multimedia messages). All text messages sent over 2G are digitally encrypted, allowing for the transfer of data in such a way that only the intended receiver can receive and read it.





  • https://github.com/ptrkrysik/gr-gsm - based on the gsm-receiver written by Piotr Krysik (also the main author of gr-gsm) for the Airprobe project.The aim is to provide set of tools for receiving information transmitted by GSM equipment/devices.

2.5G

2.75G


WAP

  • https://en.wikipedia.org/wiki/Wireless_Application_Protocol - a technical standard for accessing information over a mobile wireless network. A WAP browser is a web browser for mobile devices such as mobile phones that uses the protocol. Introduced with much hype in 1999,[1] WAP achieved some popularity in the early 2000s, but by the 2010s it had been largely superseded by more modern standards. Most modern handset internet browsers now fully support HTML, so do not need to use WAP markup for webpage compatibility, and most of them are no longer able to render and display pages written in WAP.


  • Kannel - a compact and very powerful open source WAP and SMS gateway, used widely across the globe both for serving trillions of short messages (SMS), WAP Push service indications and mobile internet connectivity.

SMS

  • https://en.wikipedia.org/wiki/SMS - Short Message Service is a text messaging service component of most telephone, World Wide Web, and mobile device systems. It uses standardized communication protocols to enable mobile devices to exchange short text messages. An intermediary service can facilitate a text-to-voice conversion to be sent to landlines. SMS was the most widely used data application, with an estimated 3.5 billion active users, or about 80% of all mobile subscribers, at the end of 2010.

SMS, as used on modern devices, originated from radio telegraphy in radio memo pagers that used standardized phone protocols. These were defined in 1985 as part of the Global System for Mobile Communications (GSM) series of standards. The protocols allowed users to send and receive messages of up to 160 alpha-numeric characters to and from GSM mobiles. Although most SMS messages are mobile-to-mobile text messages, support for the service has expanded to include other mobile technologies, such as ANSI CDMA networks and Digital AMPS. SMS is also employed in mobile marketing, a type of direct marketing.According to one market research report, as of 2014, the global SMS messaging business was estimated to be worth over $100 billion, accounting for almost 50 percent of all the revenue generated by mobile messaging.








  • https://en.wikipedia.org/wiki/Multimedia_Messaging_Service - a standard way to send messages that include multimedia content to and from a mobile phone over a cellular network. Users and providers may refer to such a message as a PXT, a picture message, or a multimedia message.[1] The MMS standard extends the core SMS (Short Message Service) capability, allowing the exchange of text messages greater than 160 characters in length. Unlike text-only SMS, MMS can deliver a variety of media, including up to forty seconds of video, one image, a slideshow[2] of multiple images, or audio.



  • https://en.wikipedia.org/wiki/Rich_Communication_Services - a communication protocol between mobile-telephone carriers and between phone and carrier, aiming at replacing SMS messages with a text-message system that is richer, provide phonebook polling (for service discovery), and transmit in-call multimedia

3G UMTS

  • https://en.wikipedia.org/wiki/3G - standing for third generation, is the third generation of wireless mobile telecommunications technology. It is the upgrade for 2G and 2.5G GPRS networks, for faster internet speed. This is based on a set of standards used for mobile devices and mobile telecommunications use services and networks that comply with the International Mobile Telecommunications-2000 (IMT-2000) specifications by the International Telecommunication Union. 3G finds application in wireless voice telephony, mobile Internet access, fixed wireless Internet access, video calls and mobile TV.

3G telecommunication networks support services that provide an information transfer rate of at least 0.2 Mbit/s. Later 3G releases, often denoted 3.5G and 3.75G, also provide mobile broadband access of several Mbit/s to smartphones and mobile modems in laptop computers. This ensures it can be applied to wireless voice telephony, mobile Internet access, fixed wireless Internet access, video calls and mobile TV technologies.


  • https://en.wikipedia.org/wiki/Node_B - the telecommunications node in particular mobile communication networks, namely those that adhere to the UMTS standard. The Node B provides the connection between mobile phones (UEs) and the wider telephone network. UMTS is the dominating 3G standard. Node B corresponds to BTS (base transceiver station) in GSM.




  • https://en.wikipedia.org/wiki/UMTS - The Universal Mobile Telecommunications System (UMTS) is a third generation mobile cellular system for networks based on the GSM standard. Developed and maintained by the 3GPP (3rd Generation Partnership Project), UMTS is a component of the International Telecommunications Union IMT-2000 standard set and compares with the CDMA2000 standard set for networks based on the competing cdmaOne technology. UMTS uses wideband code division multiple access (W-CDMA) radio access technology to offer greater spectral efficiency and bandwidth to mobile network operators.UMTS specifies a complete network system, which includes the radio access network (UMTS Terrestrial Radio Access Network, or UTRAN), the core network (Mobile Application Part, or MAP) and the authentication of users via SIM (subscriber identity module) cards.The technology described in UMTS is sometimes also referred to as Freedom of Mobile Multimedia Access (FOMA)[1] or 3GSM.Unlike EDGE (IMT Single-Carrier, based on GSM) and CDMA2000 (IMT Multi-Carrier), UMTS requires new base stations and new frequency allocations.

3.5G / HSPA

3.75G / HSPA+

3.95G / LTE

  • https://en.wikipedia.org/wiki/LTE_(telecommunication) - a standard for wireless broadband communication for mobile devices and data terminals, based on the GSM/EDGE and UMTS/HSPA technologies. It increases the capacity and speed using a different radio interface together with core network improvements. The standard is developed by the 3GPP (3rd Generation Partnership Project) and is specified in its Release 8 document series, with minor enhancements described in Release 9. LTE is the upgrade path for carriers with both GSM/UMTS networks and CDMA2000 networks. The different LTE frequencies and bands used in different countries mean that only multi-band phones are able to use LTE in all countries where it is supported.

LTE is commonly marketed as "4G LTE and Advance 4G", but it does not meet the technical criteria of a 4G wireless service, as specified in the 3GPP Release 8 and 9 document series for LTE Advanced. LTE is also commonly known as 3.95G. The requirements were originally set forth by the ITU-R organization in the IMT Advanced specification. However, due to marketing pressures and the significant advancements that WiMAX, Evolved High Speed Packet Access and LTE bring to the original 3G technologies, ITU later decided that LTE together with the aforementioned technologies can be called 4G technologies. The LTE Advanced standard formally satisfies the ITU-R requirements to be considered IMT-Advanced. To differentiate LTE Advanced and WiMAX-Advanced from current 4G technologies, ITU has defined them as "True 4G".



4G

  • https://en.wikipedia.org/wiki/4G - the fourth generation of broadband cellular network technology, succeeding 3G. A 4G system must provide capabilities defined by ITU in IMT Advanced. Potential and current applications include amended mobile web access, IP telephony, gaming services, high-definition mobile TV, video conferencing, and 3D television. The first-release Long Term Evolution (LTE) standard (a 4G candidate system) has been commercially deployed in Oslo, Norway, and Stockholm, Sweden since 2009. It has, however, been debated whether first-release versions should be considered 4G.


  • https://en.wikipedia.org/wiki/LTE_Advanced - a mobile communication standard and a major enhancement of the Long Term Evolution (LTE) standard. It was formally submitted as a candidate 4G to ITU-T in late 2009 as meeting the requirements of the IMT-Advanced standard, and was standardized by the 3rd Generation Partnership Project (3GPP) in March 2011 as 3GPP Release 10.


5G


DIY

  • Osmocom - an umbrella project regarding Open source mobile communications. This includes software and tools implementing a variety of mobile communication standards, including GSM, DECT, TETRA and others.
    • Cellular Infrastructure - a group of Osmocom programs implementing cellular network infrastructure components for GSM, GPRS, EDGE, UMTS, HSPA, LTE and their associated interfaces and protocol stacks.


  • OpenBTS - a Linux application that uses a software-defined radio to present a standard 3GPP air interface to user devices, while simultaneously presenting those devices as SIP endpoints to the Internet. This forms the basis of a new type of wireless network which promises to expand coverage to unserved and underserved markets while unleashing a platform for innovation, including offering support for emerging network technologies, such as those targeted at the Internet of Things.


  • UmTRX - The industrial grade dual-channel wide-band SDR transceiver.


  • UmSITE-TM3 - A complete mobile network in a single tower mounted base station, one of the key components of the Fairwaves GSM network architecture. Technical details: Osmocom or OpenBTS software suites (Osmocom by default). Ability to run GnuRadio and other SDR software. Output power - 3W per channel (6W total). UmSITE includes internal duplexers and amplifiers. 1-3 km coverage (with external antennas). Two independent TRX's, i.e. two ARFCNs. Based on UmTRX transceiver. Stable reference clocks: 26MHz TCXO (integer multiple of GSM sample rate) with 100ppb frequency stability. DAC for TCXO frequency fine tuning. Integrated GPS module for automatic TCXO frequency stabilization.


  • ZeroPhone - an open-source smartphone that can be assembled for 50$ in parts. It is Linux-powered, with UI software written in Python, allowing it it to be easily modifiable - and it doesn't prohibit you from changing the way it works.


Software-defined radio



  • Opendigitalradio.org – Open techniques for Digital Radio Broadcasting. What we do: We promote digital radio broadcasting; We develop the ODR-mmbTools free open source software used in many small-scale DAB broadcast projects; We maintain a knowledge base about digital radio in form of a wiki.
  • Opendigitalradio.org wiki - Open digital broadcasting techniques based on software defined radio. Digital radio transmission and development must also become democratized for experimenters and small broadcasters. Opendigitalradio.org wiki is about creating a community for documenting and exchanging experimentations and gather information about existing small-scale DAB projects. Please read Introduction for more information. Opendigitalradio is a non-profit association based in Switzerland (page in french), offering also a broadcast infrastructure for temporary radio stations.


Software


GNU Radio





running the "volk_profile" gnuradio utility will detect and enable processor specific optimisations and will in many cases give a significant performance boost.


  • https://github.com/tapparelj/gr-lora_sdr - fully-functional GNU Radio software-defined radio (SDR), implementation of a LoRa transceiver with all the necessary receiver components to operate correctly even at very low SNRs. The transceiver is available as a module for GNU Radio 3.10. This work has been conducted at the Telecommunication Circuits Laboratory, EPFL. In the GNU Radio implementation of the LoRa Tx and Rx chains the user can choose all the parameters of the transmission, such as the spreading factor, the coding rate, the bandwidth, the sync word, the presence of an explicit header and CRC.[30]

Gqrx


LuaRadio

  • LuaRadio is a lightweight, embeddable flow graph signal processing framework for software-defined radio. It provides a suite of source, sink, and processing blocks, with a simple API for defining flow graphs, running flow graphs, creating blocks, and creating data types. [31]

liquid-dsp

  • liquid-dsp - a free and open-source signal processing library for software-defined radios written in C. Its purpose is to provide a set of extensible DSP modules that do not rely on external dependencies or cumbersome frameworks.

CubicSDR

FreeDV

  • FreeDV - a Digital Voice mode for HF radio. You can run FreeDV using a free GUI application for Windows, Linux and OSX that allows any SSB radio to be used for low bit rate digital voice.

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DAB

  • welle.io - an open source DAB and DAB+ software defined radio (SDR) with support for rtl-sdr (RTL2832U) and airspy. It supports high DPI and touch displays and it runs even on cheap computers like Raspberry Pi 2/3 and 100€ China Windows 10 tablets.


  • https://github.com/JvanKatwijk/qt-dab - for Windows, Linux and Raspberry Pi for listening to terrestrial Digital Audio Broadcasting (DAB and DAB+). It is the successor of both DAB-rpi and sdr-j-DAB, two former programs by the same author.


  • https://github.com/JvanKatwijk/dab-cmdline - provides entries for the functionality to handle DAB/DAB+ through some simple calls. A few callback functions provide the communication back from the library to the caller. The library interface is given in dab-api.h



  • Google Play: Wavesink DAB/FM Trial - Turn your phone or tablet into a DAB and FM-Stereo RDS receiver. On USB-OTG compatible phones, simply connect a cheap USB dongle and listen to VHF radio in HiFi quality. Note that the trial version has a runtime limitation and does not support DAB+ but only DAB and FM/RDS.


DVB-S

sdrtrunk

  • https://github.com/DSheirer/sdrtrunk - A cross-platform java application for decoding, monitoring, recording and streaming trunked mobile and related radio protocols using Software Defined Radios (SDR).

Universal Radio Hacker

  • https://github.com/jopohl/urh - a complete suite for wireless protocol investigation with native support for many common Software Defined Radios. URH allows easy demodulation of signals combined with an automatic detection of modulation parameters making it a breeze to identify the bits and bytes that fly over the air. As data often gets encoded before transmission, URH offers customizable decodings to crack even sophisticated encodings like CC1101 data whitening. When it comes to protocol reverse-engineering, URH is helpful in two ways. You can either manually assign protocol fields and message types or let URH automatically infer protocol fields with a rule-based intelligence. Finally, URH entails a fuzzing component aimed at stateless protocols and a simulation environment for stateful attacks.

SDRPlusPlus

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  • https://github.com/rxseger/rx_tools - rx_fm, rx_power, and rx_sdr tools for receiving data from SDRs, based on rtl_fm, rtl_power, and rtl_sdr from librtlsdr, but using the SoapySDR vendor-neutral SDR support library instead, intended to support a wider range of devices than RTL-SDR.




  • Identification Guide - wiki intended to help identify radio signals through example sounds and waterfall images. Most signals are received and recorded using a software defined radio such as the RTL-SDR, Airspy, SDRPlay, HackRF, BladeRF, Funcube Dongle, USRP or others.






Telephony

  • http://openbts.org/
    • OpenBTS - a Unix application that uses a software radio to present a GSM air interface to standard 2G GSM handset and uses a SIP softswitch or PBX to connect calls. (You might even say that OpenBTS is a simplified form of IMS that works with 2G feature-phone handsets.) The combination of the global-standard GSM air interface with low-cost VoIP backhaul forms the basis of a new type of cellular network that can be deployed and operated at substantially lower cost than existing technologies in many applications, including rural cellular deployments and private cellular networks in remote areas.

Web SDR



  • SDR.hu - On sdr.hu, you can find SDR receivers that amateur radio operators shared, so you can listen to radio signals without even having to buy any SDR hardware! In fact, amateur radio is a great thing and also lets you experiment with transmitting on the air, by using various frequency bands and modulations.



Hardware



  • Myriad RF is a family of open source hardware and software projects for wireless communications, and a community that is working to make wireless innovation accessible to as many people as possible.






RTL-SDR

  • http://sdr.osmocom.org/trac/wiki/rtl-sdr - RTL-SDR is a set of tools that enables DVB-T USB dongles based on the Realtek RTL2832U chipset to be used as cheap software defined radios, given that the chip allows transferring raw I/Q samples from the tuner straight to the host device.


The frequency range of the RTL2832U / E4000 is generally around 64MHZ to 1700MHz with a gap around 1100MHz to 1250MHz. The RTL2832U / R820T frequency range is 24MHZ to roughly 1850MHz with no gaps (found yet), and no DC offset spike. RTL dongles have 2.4 MHz of useful bandwidth.




  • https://github.com/rxseger/rx_tools - rx_fm, rx_power, and rx_sdr tools for receiving data from SDRs, based on rtl_fm, rtl_power, and rtl_sdr from librtlsdr, but using the SoapySDR vendor-neutral SDR support library instead, intended to support a wider range of devices than RTL-SDR. Old!







  • Rtl Power - a unix-hacker's approach to the waterfall. Its unique features include:Just getting started with rtl_power, and it looks like just the to... Unlimited frequency range. You can do the whole 1.7GHz of a dongle. Unlimited time. At least until you run out of disk for logging. Unlimited FFT bins. But in practice I don't think I've taken it above 100k bins. Quantitative rendering. Exact power levels are logged. Runs on anything. A slower computer will use less samples to keep up.








  • https://github.com/theori-io/nrsc5 - This program receives NRSC-5 digital radio stations using an RTL-SDR dongle. It offers a command-line interface as well as an API upon which other applications can be built. Before using it, you'll first need to compile the program using the build instructions below. [40]
  • https://github.com/cmnybo/nrsc5-gui - a graphical interface for nrsc5. It makes it easy to play your favorite FM HD radio stations using an RTL-SDR dongle. It will also display weather radar and traffic maps if the radio station provides them.

Broadcom Wi-Fi chips

  • https://github.com/seemoo-lab/mobisys2018_nexmon_software_defined_radio - This projects demonstrates our discovery that turns Broadcom's 802.11ac Wi-Fi chips into software-defined radios that transmit arbitrary signals in the Wi-Fi bands. In this example, we patch the Wi-Fi firmware of BCM4339 devices installed in Nexus 5 smartphones and BCM43455c0 devices installed in Raspberry Pi B3+ computers. The Raspberry Pi B3 will never be supported as it only contains an 802.11n PHY. The firmware patch utilises three ioctls. [41]

RaspberryPI

WSPR-Pi


PiFM



PirateRadio
rpitx


  • https://github.com/felixzero/rpitx_alsa - An ALSA sound driver interface for sending samples to F5OEO's rpitx. This is only a proof-of-concept demo. It should work, but it is in no way complete and/or perfect.
PiFmRds
PiFmAdv


jackpifm
tesla_coil_fm_driver
  • https://github.com/coup-de-foudre/tesla_coil_fm_driver - Project forked from PNPtutorials.Use Raspberry Pi as FM transmitter. Works on any RPi board.This project uses the general clock output to produce frequency modulated radio communication. It is based on idea originaly posted here but does not use DMA controller in order to distribute samples to output (clock generator), so sound quality is worse as in PiFm project and only mono transmition is available but this makes possible to run it on all kind of boards.


PiAmp
  • PiAmp - Raspberry Pi FM transmitter amp and filter


CaribouLite

FL2000

  • osmo-fl2k - Since rtl-sdr has been released a couple of years ago, cheap SDR receivers are ubiquitous. SDRs with transmission capability have become cheaper as well, but are still more expensive. osmo-fl2k allows to use USB 3.0 to VGA adapters based on the Fresco Logic FL2000 chip, which are available for around $5, as general purpose DACs and SDR transmitter generating a continuous stream of samples by avoiding the HSYNC and VSYNC blanking intervals.








FT232RL


HackRF

  • https://en.wikipedia.org/wiki/HackRF_One - a wide band software defined radio (SDR) half-duplex transceiver created and manufactured by Great Scott Gadgets. Its creator, Michael Ossmann, launched a successful KickStarter campaign in 2014 with a first run of the project called HackRF (Project Jawbone). The hardware and software's open source nature has attracted hackers, amateur radio enthusiasts, and information security practitioners.


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  • RootIO Radio - a technology platform for low cost, hyperlocal community radio stations. Tiny FM radio stations that require little investment, maintenance, or contribution from the community, yet at the same time offer more and better modes of interaction than traditional stations. After a few days of installation and training, stations can start to facilitate new economic opportunities, new opportunities for expression and deliberation, and provide information across, into, and out of the community they serve.Each station is amplified by our cloud/telephony Radio as a Service (RaaS). With the cloud, an individual station can receive free voice-quality calls that go straight to air, download audio from the Internet in the background, or run SMS votes. Using any basic phone (through RaaS) local hosts can run live shows with callers; local business people can record ads or announcements; citizen journalists can cover live meetings or sports events. With solar power a station can serve as 24/7 endpoint to emergency services.Four stations have been running in Northern Uganda for the last year, and small rural communities are creating their own programs, reporting their own news, and requesting audio content from the Internet. RootIO, with the help of Resilient Africa Network, is hoping to launch another 20 stations in the coming year.


  • RadioWitness - Immutable, peer-to-peer archiving and distribution of police radio calls. Authors use Software-Defined Radios and Dat Archives to record local police radio. Publishers seed archives from Authors and then re-distribute them to larger audiances. Other rolse arise too, such as Studios who synthesize radio archives into archives of audible speech, and Indexers who aggregate metadata on individual radio calls. Stop by #radiowitness on freenode and say hi.




RFID

  • https://en.wikipedia.org/wiki/Radio-frequency_identification - uses electromagnetic fields to automatically identify and track tags attached to objects. The tags contain electronically stored information. Passive tags collect energy from a nearby RFID reader's interrogating radio waves. Active tags have a local power source (such as a battery) and may operate hundreds of meters from the RFID reader. Unlike a barcode, the tag need not be within the line of sight of the reader, so it may be embedded in the tracked object. RFID is one method of automatic identification and data capture (AIDC).


  • https://en.wikipedia.org/wiki/Microchip_implant_(animal) - an identifying integrated circuit placed under the skin of an animal. The chip, about the size of a large grain of rice, uses passive RFID (Radio Frequency Identification) technology, and is also known as a PIT (Passive Integrated Transponder) tag.Externally attached microchips such as RFID ear tags are commonly used to identify farm and ranch animals, with the exception of horses. Some external microchips can be read with the same scanner used with implanted chips.



  • https://github.com/Proxmark/proxmark3 - a powerful general purpose RFID tool, the size of a deck of cards, designed to snoop, listen and emulate everything from Low Frequency (125kHz) to High Frequency (13.56MHz) tags.This repository contains enough software, logic (for the FPGA), and design documentation for the hardware that you could, at least in theory, do something useful with a proxmark3.