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Real Time DGPS Data Acquisition of Airborne Vehicle and Display software in Integrated test range
To fulfill the above objective, Range validation helicopter/ aircraft sortie has been conducted in Test Range. During sortie, all the tracking sensors deployed at various sites track the target. At the same time rover GPS receiver set installed in helicopter/ aircraft (i.e. on board) also provides positional information of helicopter/aircraft. The GPS reference station is installed at precisely surveyed benchmark location. In real time RTCM corrections are transmitted from reference station to rover station by UHF Trans-receiver communication antenna installed at reference station. The same antenna is receiving the rover station positional information from air born object. The positional information derived from GPS along with the other tracking sensors has been displayed. Sortie controller identifies GPS and other tracking sensor position using different color displays and accordingly he is giving instruction to pilots as per the range instrumentation requirements in real time. For this purpose, a real time DGPS data Acquisition and display software has been developed [2].
3. Details of system configuration and data Acquisition and display software The basic DGPS system configuration for a typical calibration sortie is given below 
The rover receiver is on the aircraft/helicopter and reference receiver is on the benchmark. In this case the two receivers communicate in real time over radio channel with the help of radio modem associated with each of them, radio modem works in half-duplex mode using TDMA, means it can either transmit or receive at any one instant. In fact, it takes a finite amount of time to change from transmission to reception mode. |