线性调频脉冲压缩雷达信号参数估计方法

针对低信噪比下,瞬时自相关谱算法对调频率估计精度不够高及基于传统的包络检波方法对线性调频(LFM)脉宽和重复间隔估计不准确的问题,提出了以分数阶傅里叶变换为核心的多参数估计方法.利用分数阶傅里叶变换对LFM信号的聚集特性,精确估计LFM脉冲压缩雷达信号各主要参数,设计LFM脉冲压缩信号发射接收实验以验证本算法.实验结果表明,在较低信噪比条件下,能够实现线性调频脉冲雷达信号主要参数的准确估计.

Parameters Estimation Algorithm of LFM Pulse Compression Radar Signal

Under low signal noise ratio, estimation accuracy using classical algorithms, such as envelope-demodulation and instant autocorrelation spectrum, can't satisfy with the system requirements. To enhance the estimating accuracy of pulse repetition interval, pulse width and frequency modulation rate, an integrated method of multi-parameter estimation is proposed based on fractional Fourier transform (FRFT) in this paper. The focusing capability of FRFT was used for linear frequency modulation (LFM) signal and the relativity of estimation algorithm for each parameter was considered. Moreover, the founded test platform was utilized that transmits and receives LFM pulse compression radar signal to do a trial on algorithm. The results demonstrate its feasibility. The proposed method could not only get high estimation accuracy but also have good ability in real-time processing.