Sodelobe Suppression Technology Basing On APC

The rapid development of modern stealth technology and extensive use of lowaltitude penetration technology, makes the target have smaller RCS and lower SCR. high-resolution technology is one of the effective ways to solve the detection of low RCS targets and low SNR targets.. As two main HRRP formation methods, pulse compression and synthetic broadband technology can not obtain the ideal low range sidelobes, and result in high-intensity targets covering the dim goals around them. In this paper, adaptive pulse compression(APC) technology is stuided to reduce the high sidelobes in the high-resolution imaging process and to improve dim target detection capability. This dissertation is organized as follows:The second chapter first introduces the principle of traditional pulse compression and matched filter, and analyzes the sidelobe suppression performance of several window functions that commonly used in matched filter. Then for the LFM signal waveform, introduces the basic principles and steps of APC algorithm based on the minimum mean square error(MMSE). The simulation results show that compared to the traditional windowed sidelobe suppression methods, APC can suppress the sidelobes better, improve the signal range resolution, and detect the dim targets that covered by sidelobes of strong targets better.The third chapter constructs the APC algorithm model for the stepped frequency(SF) radar, and deduces the algorithm and steps of SF APC based on the criteria of reiterative minimum mean square error(RMMSE). Simulation experimental results show that the APC algorithm can reduce the high sidelobes of IFFT method, and has a better sidelobe suppression power than the windowed processing. It can overcome mainlobe broadening and improve the performance of dim target detection in neighboring multi-target scenarios. Then for moving targets scene, the requirement of velocity compensation for moving target is analyzed, and the algorithm and steps of SF APC after velocity compensation is deduced. The simulation results show that, APC with different compensated velocity has a better sidelobe suppression effect than IFFT method and the windowed processing.In the forth chapter, we extend the APC algorithm in the range domain to the space- range domain and introduce space-range adaptive pulse compression(SR-APC) algorithm to suppress sidelobes in azimuth and range simultaneously according to the space-time adaptive processing(STAP) method. Simulation results show that SR-APC algorithm can suppress sidelobe in the azimuth and range better than MF, and resolve the dim target in the two-dimensional imaging of neighboring multi-objective scene. Then we propose a dimension reduced version of SR-APC algorithm, and simulation results demonstrate that it can reduce the computation complexity in the premise of limited capacity reduction in sidelobe suppression.