Tracking a target in the Advanced Airborne Interceptor Simulator with a second-order filter using TSPI from the RAJPO GPS data link
Joseph H. Nguyen, William D. Holley, Harold F. Casey · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1998
The Advanced Airborne Interceptor Simulator (AAIS) is a pod- mounted system that simulates RF emission of an airborne tracking radar. The simulator does not contain a receiver. It is a 'smart' emitter which uses the time, space and position information (TSPI) received form a target carrying a RAJPO GPS datalink pod. The TSPI essentially replaces outputs typically seen in a radar receiver, namely angle, range and range rate of a target. Since the update rate of this information is dictated by the slow transmission rate of the RAJPO datalink, the signal must be extrapolated and filtered at a much faster rate, close to that of the simulated airborne interceptor. This is necessary to accurately track and faithfully emit radar signals to maintain track on an airborne target. The received TSPI rate is 10 Hz. A second order (alpha) -(beta) filter is chosen to optimize the tracking performance of the AAIS. This paper discusses various rates of the filter, the need for extrapolation and the optimal values of the (alpha) and (beta) factors for this airborne application.