Aircraft monitoring in remote areas via the low-orbit satellite communications system “Iridium” along with the GSM data transmission through ASC-6 telemetry terminal

One of the most important aims of air traffic control is continuous positioning of aircraft, which makes it possible to control a given flight plan and record deviations from the route, along with organizing search and rescue operations in case of an accident or a disaster. Great difficulties arise when performing this task in areas where there is no radar station in the mountains, forests, at high latitudes or at extremely low altitudes. This problem can be solved by using satellite navigation systems, satellite communication systems and automatic vehicle monitoring. In order to communicate with the control center, it is advisable to transmit data packets of up to 340 bytes contain- ing information about the location of the aircraft and its status. This can be done via GSM mobile networks, and in areas where there is no communication of this kind, via the satellite communications system “Iridium”. To put these two possible ways of communication into practice, the aircraft must have on board an ASC-6 GLONASS / GPS terminal (a vehicle-compatible modification), which determines location, speed and heading of the aircraft. It is also able to reg- ister a number of other parameters, such as the status of the analog / discrete inputs, and RS-232 connected sensors indications. This makes it possible to transmit to the control center not only the geographical position data, but also the speed of the aircraft and other operational data. A special communication module SM-1 can be used to support the sat- ellite communication, as it is ASC-6 compatible through RS-232 interface.