Cogent Airborne Surveillance Transmitter (AST2)
The new Cogent Airborne Surveillance Transmitter (AST2) is designed for modern airborne operations where it is necessary to carry live HD video from the airborne platform to the ground. It also has an option to maintain bi-directional connectivity between the platform and the ground, using a secure data link, for remote control and communications.
The high power transmitter is installed on the airborne platform and carries SDI signals from the EOIR sensor. This digital interface is compatible with a number of manufacturers. The optional Datalink system carries a number of data channels which are multiplexed onto the high power RF radio bearer for transmission. Advanced DVB-T2 modulation is used to make optimum use of the latest COFDM transmission technology. This provides enhanced range and durability ensuring minimal outages of the signal on the ground. Ethernet and serial data communication (RS-232, RS-422 or RS-485) signals are carried on the datalink sub-system.
At the ground receiving point a high gain hemispherical antenna is used to receive the signals, and the platform is tracked using GPS signals carried over the link. The data-link carries the ethernet signals as well as RS232 and RS 422/485 signals, these are present on the data link transceiver on the ground.,The HD video is extracted form the signal and this is decoded in the Cogent 2HD rack mount receiver.
The optional datalink can also be equipped with a WiFi antenna and an embedded RF filter to enable Wi-Fi connectivity on board the airborne platform. The Ground Datalink can also be equipped with 3G/4G antenna, and an embedded RF filter to enable a 3G/4G back-up connection.