Prc-cw Radar At Close Range Goal Of Adaptive Interference Cancellation

Because of adopting spectrum-spread technology, the PRC-CW radar have an excellent ability of LPI and counter electronic countermeasures of electric interference.But the interference of close-in targets is also a serious problem to PRC-CW radar, it affects the performance of the radar. Eliminating and supressing of Doppler interference of close-in targets of PRC-CW radar are studied.In this thesis, we first introduce the basic principle of the PRC-CW radar and the reason of interference of close-in targets. After studying the former's way of eliminating the Doppler interference of close-in targets, then we propose an adaptive suppress system to suppress the Doppler interference of close-in targets in the PRC-CW radar, the algorithm of the adaptive filter is LMS. The performance of this system and the condition of using this system is analyzed with Winer Filter theory.Secondly, based on the LMS algorithm,\ve have done a lot of simulation to further analyze the performance of the adaptive suppressing system ,and many important parameters,such as adaptive step, adaptive filter lenth,sampling frequecy of the system and the frequency difference beteween useful singal and interference signal. The results of smulation show the adaptive eliminating system have a good performance.At the same time, a proper range of parameter values mentioned above is confirmed, it is a good reference to practical implementation of the adaptive eliminating system.At last, we use our adaptive eliminating system to suppress the practial measured signal of close-in targets, the suppressing rate can achieve 20dB.Then we use fix-point digital signal processer(DSP) to implement the adaptive eliminating system and it's performance meet the specification of practical application.