摘要
当目标的多普勒频率与FFT滤波器组不精确匹配时,会产生FFT的高副瓣现象。利用加窗FFT可以抑制副瓣,但降低了主瓣信噪比。在WFFT输出端利用离散小波变换(discrete wavelet transform,DWT)可以改善雷达处理增益(processing gain,PG),推导了单边形式WFFT-DWT的处理增益公式,并利用FFT/WFFT-DWT进一步提高雷达处理增益。检测性能分析表明,FFT/WFFT-DWT在存在频率偏移时有比FFT/FFT-DWT和FFT更好的检测性能。
When Doppler frequency of target does not match the FFT bin frequencies exactly, the high side lobe appears. The weighed FFT （WFFT） can suppress the side lobe but decrease the SNR in main lobe. Discrete wavelet transform （DWT） was applied to output of WFFT to recover processing gain （PG） lost from non-optimum input signals. And then FFT/WFFT-DWT was proposed to improve PGfurther. Results of PG and detectability analysis demonstrate that FFT/WFFT-DWT can attain much higher detectability than FFT/FFT-DWT as well as FFT especially in unmatched state.
出处
《系统仿真学报》
EI
CAS
CSCD
北大核心
2007年第8期1879-1882,共4页
Journal of System Simulation
基金
全国优秀博士学位论文作者专项基金(200237)
关键词
雷达信号检测
离散小波变换
WFFT
处理增益
MTD
radar signal detection
discrete wavelet transform
weighted fast Fourier transform
processing gain
MTD
