CAJ | 학술논문

介绍了采用调频广播作为外辐射源的无源雷达，因FM广播载频高和带宽窄，采用窄带采样定理可以保证在信号无失真采样的前提下大大降低采样频率，为实时信号处理提供方便。另外，目标回波会受到较强的直达波干扰影响，由于多普勒频移相对较小，目标回波与直达波干扰频谱混叠严重，使用经典滤波器进行直达波干扰抑制十分困难。因此，设计了基于最小均方的自适应回波重建系统，仿真表明，直达波干扰抑制效果明显，目标回波得到较好重建，自适应回波重建系统工作性能良好。
개소료채용조빈엄파작위외복사원적무원뢰체，인FM엄파재빈고화대관착，채용착대채양정리가이보증재신호무실진채양적전제하대대강저채양빈솔，위실시신호처리제공방편。령외，목표회파회수도교강적직체파간우영향，유우다보륵빈이상대교소，목표회파여직체파간우빈보혼첩엄중，사용경전려파기진행직체파간우억제십분곤난。인차，설계료기우최소균방적자괄응회파중건계통，방진표명，직체파간우억제효과명현，목표회파득도교호중건，자괄응회파중건계통공작성능량호。
Passive radar based on freq uency modulation broadcast is introduced. Because of its high-carrier-frequency and narrow-band,sampling frequency can be reduced greatly using narrowband sampling theorem,which is helpful to real-time signal processing. Moreover,echo signals are interfered seriously by strong direct-path wave. Because Doppler shift is relatively small,frequency spectrums of echo signal and direct-path wave interference overlap seriously. Obviously,classic filter is helpless in this case. Therefore,adaptive echo reconstruction system based on least mean square is designed. Simulation shows that direct-path wave interference has greatly been suppressed and echo signals have successfully been reconstructed,which indicates that the designed system is effective.