摘要
在无源双基地雷达系统中,动目标的时延和多普勒频移估计是通过计算直达波信号和目标回波信号的互模糊函数来实现的。提出了首先利用级联积分梳状滤波器(CIC滤波器)对不同时延的互模糊函数进行抽取,然后进行FFT变换的动目标快速检测算法。CIC滤波器在数据抽取过程中能够有效抑制频率混叠干扰及通带信号衰减问题,同时由于信号采样频率的降低,FFT变换的频率分析范围将大大减小,从而明显提高信号处理速度。该算法可以从任意距离单元开始估计目标的多普勒频移,所以可以对数据进行并行处理,这将进一步提高信号检测和处理速度。最后,利用仿真数据验证了该算法的有效性。
In passive bistatic radar system, the joint time delay and the Doppler shift estimation of mov- ing target are based on the cross ambiguity function（CAF） between direct-path signals and target echoes. A fast processing algorithm is proposed based on the cascaded integrator comb filter（CIC filter） which can effi- ciently restrain the frequency atiasing and passband attenuation during data decimation processing. The im- proved algorithm needs several extra steps to decimate the signals, while greatly reduces the overall computa- tion complexity for much depressing sample frequency with almost no influence on the signal detection. The algorithm can compute the target Doppler shift of any range bins. To increase the processing speed further, the algorithm can be parallelized amongst different computers. Finally, the improved algorithm is verified by simulated data.
出处
《雷达科学与技术》
2013年第2期145-149,共5页
Radar Science and Technology
