雷达信号脉冲压缩及多普勒敏感性分析.pdfVIP

摘 要 常规的单脉冲雷达无法同时兼顾距离分辨力以及作用距离，脉冲压缩技术能 够有效解决这个矛盾，因而被广泛应用。然而，脉冲压缩回波信号旁瓣以及多普 勒频移都会对测量精度造成影响，因此，关于信号旁瓣和多普勒频移对不同的脉 冲压缩信号的影响程度以及补偿方法的研究具有重要意义。 本文主要对脉冲压缩信号中比较常用的线性调频信号和相位编码信号的脉压 特性及多普勒敏感性展开研究。通过仿真模拟并结合实测数据，分析了窗函数加 权方式对线性调频信号旁瓣抑制的效果，针对线性调频信号在多普勒频移存在的 情况下，由于距离-速度耦合而产生的测距误差，采用上升下降调频多普勒补偿算 法进行校正。分析相位编码信号的脉压特性时，以典型的M 序列码作为研究对象， 采用最小二乘法及迭代加权最小二乘法进行旁瓣抑制，效果比较明显。对于 M 序 列码的多普勒敏感性，研究了多普勒频移对于脉压信号的影响以及由于码长、子 脉冲宽度的不同取值对信号多普勒敏感性的影响。利用基于交替 M 序列的多普勒 补偿算法消除多普勒频移的影响，仿真结果表明此方法能有效对消掉回波中的多 普勒频移，达到补偿目的。 关键词：脉冲压缩信号 旁瓣抑制 多普勒敏感性 Abstract Conventional single-pulse radar can not take into account the distance resolution as well as the operating range. Pulse compression technology can effectively resolve this conflict, so it have been widely used.However, the sidelobes of pulse compression echo signals and the Doppler frequency shift will have an impact on the measurement accuracy.Therefore, the degree of influence from sidelobe and Doppler shift to different pulse compression signal as well as the compensation method to the influence are important to be researched. Pulse compression and Doppler sensitivity of the linear frequency modulation signal(LFM) and the phase-encoded signal which are commonly used from pulse compression signals are studied in this paper. With the Combination of measured data and simulation,the side lobe suppression effect to the LFM signal by weighted window function is analyzed.The upping and downing frequency modulation compensatory algorithm for the LFM is used for regulating the ranging error due to distance - speed coupled in the presence of Doppler frequency shift.M-sequence code as the object of study,Least Square algorithm and Iterative Weighted Least Square algorithm are used for suppressing sidelobe, the effect is more obvious. For the Doppler