Simulation Analysis Of TACAN Signal Processing And Scheme Design Of Hardware System

TACAN is a short-range radio navigation system, designed to measure the bearing anddistance that ground station relative to plane. It is a navigation equipment used widely, andwas applied to the aircraft carrier at first, which would give distance-bearing information tohigh accuracies for fighter aircraft. Therefore, reconnaissance receiving and processingtechnique for TACAN signal is very important.In this paper, we mainly investigate the method of TACAN signal sorting andrecognition and the method of getting its bearing information, then give the implementscheme of the hardware. We get the single signal source of TACAN through pre-sorting usingRF, PA and PW. The major reference group and auxiliary reference group are sorted fromTACAN signal by template matching method, because the signal form is known and itsparameters are invariant.Then phase difference between reference group and zero phase of envelope is calculatedto get the information on its position relative to ground station.Because zero phase ofenvelope is difficult to obtain, the phase difference between wave trough phase of envelopeand reference group is calculated to instead it. We using TACAN simulator as signal source,which could output a variety of operating modes of the TACAN signal. And the signal sortingand the bearing processing are analysed by the method that previous mentioned. Simulationresults show that the algorithm can get the precise bearing information of TACAN.We firstly introduce the development of TACAN system, the basic theory of the distancemeasuring and phase measuring of TACAN system,the antenna structure of TACAN systemand the mathematical description of TACAN signal, and secondly introduce the characteristicparameters of TACAN signal, the operating mode of TACAN system and the format ofTACAN signal. Thirdly we give the signal processing for TACAN, the sorting algorithm forTACAN, the bearing processing for TACAN and the simulation result.Finally we give theoverall structure and interface of the hardware, the choice for the chip of FPGA and DSP, thealgorithm of FPGA and its implement, the software composition of DSP.