AZN-V

Historically, AZN-B developed from the following systems:

• Mode-A - the so-called Secondary Surveillance Radar (SSR), used by both civilian and military aircraft, provides up to 4096 identification codes ( transponder code ) and is the most common and used mode. It operates at a request frequency of 1030 MHz. In Mode-A / C mode, altitude data, transponder code, and ICAO airplane code are transmitted, and coordinates are not transmitted.
• Mode-S mode “listens” at a request frequency of 1030 MHz, but responds at a frequency of 1090 MHz, modulating the D PSK signal carrier to minimize interference to other Mode A / C requests.

Only in Mode-S mode the coordinates of the aircraft are transmitted.

When the aircraft transponder receives a request from a ground-based radar, it confirms the receipt of the request by means of a Pulse-position modulation (PPM) signal at a frequency of 1090 MHz.

Regardless of the receipt of a request from a ground radar, approximately every second an extended squitter is transmitted by plane, this squitter contains the coordinates of the aircraft's location.

AZN-B is based on the GPS system (not necessarily, enough IRS ) to determine the exact coordinates of the aircraft in space. This aircraft position information is combined with other information, such as aircraft type, speed, aircraft number, flight, course, vertical speed, and is then broadcast approximately every second.

Other aircraft and ground stations equipped with AZN-V receive this information within a radius of approximately 150 miles . Ground stations combine information received from different points with additional information received from ground-based radars for non-AZN-V devices and relay data for all aircraft in the service radius.

Aircraft situation and weather information can be displayed in the cockpit if the aircraft is equipped with an AZN-V.

Types of equipment AZN-V

AZN-B - receivers (ADS-B IN) - devices of this class receive AZN-B data, but cannot transmit AZN-B data to other aircraft or ground stations. The receiver receives both traffic information and weather information. Currently, the FAA has limited the implementation of ADS-B in that ground stations will only transmit traffic data (including radar data) when they receive information from at least one ADS-B transmitter on an aircraft transmitted in the service radius. Thus, an aircraft equipped with an AZN-V receiver may not “see” traffic data if there are no aircraft with AZN-V transmitters in the service area or do not transmit a signal. Weather information is always transmitted by ground stations and is always available for reception through the ADS-B receiver on the tracks.

АЗН-В - transmitters (ADS-B OUT) - devices of this class can transmit AZN-В data. The transmitters can also “wake up” AZN-V ground stations and switch them to the mode of transmitting the air situation to aircraft in the area of ​​their operation. AZN-B devices capable of transmitting aircraft position and flight path must be FAA certified.

AZN-V- transceivers is a class of devices capable of both transmitting and receiving AZN-V data. AZN-V- transceivers can “wake up” the FAA AZN-V ground stations and switch them to the traffic transmission mode to aircraft in their coverage area. AZN-B devices capable of transmitting aircraft position and flight path must be FAA certified.

TIS-B

Traffic Information Services-Broadcast (TIS-B) is a component of AZN-V technology, which provides free air traffic viewing service for aircraft equipped with AZN-V receivers.

TIS-B allows aircraft equipped with non-AZN-B transponders to transmit their location (obtained by radar) to aircraft equipped with AZN-B.

FIS-B

Flight Information Services-Broadcast (FIS-B) is a component of ADS-B technology, which provides the distribution on the air of free weather information, time limits on flights and special information about the air situation.

From AZN-V, pilots see on the screens in the cockpit information about traffic traffic of the same type as on the screens of controllers. This greatly improves the knowledge of the situation of the pilots, as they know their position with respect to other aircraft, receive information about the deterioration of weather and information about difficult terrain.

AZN-V provides a greater margin for conflict detection, since the effective range is more than 100 miles . Pilots can see the location, course, speed and altitude of other aircraft. AZN-V provides pilots with such services as graphical display of weather conditions and textual flight recommendations at a lower cost than before, and without paid subscriptions to such services.

There are projects to monitor flying aircraft using AZN-V receivers installed by amateurs in their homes and other places. Data from these receivers via the Internet is sent to a central server, where they are collected from thousands of volunteers and amateurs and drawn on a map. Due to the fact that planes fly, as a rule, at high altitude, the range of radio visibility is sufficient to conduct observation in a radius of several thousand kilometers. In this way, it is possible to cover large areas in different countries of the world. One of the most famous of these projects is Flightradar24 .

Thanks to the use of SDR technology, the reception of AZN-V signals is possible at the lowest cost. ^[2]

• Flightradar24
• MLAT

• Russian-language resource on technology AZN-V
• The introduction of the AZN-B system in Australia , 02/01/2012
• Experience and prospects of the introduction of AZN-V in the Russian Federation (inaccessible link) // Federal State Unitary Enterprise GosNII Aeronavigation, 2011