基于多重信号分类法的线性调频差频频率估计

Frequency Estimation of LFM Difference Frequency Signal Based on MUSIC

针对傅里叶方法估计线性调频连续波差频信号频率在小尺度上精度低的缺陷,提出利用多重信号分类法(Multiple Signal Classification,MUSIC)估计差频信号频率。该方法在频域上对自相关功率谱进行信号和噪声的空间分解,利用信号空间和噪声空间的正交性,完成对信号频率的超分辨估计。仿真计算和实验室测试表明,该方法有效减小了距离分辨单元的影响,其单一目标距离测量精度优于傅里叶法。

Aiming at the low accuracy of frequency estimation of LFM difference frequency signal based on Fourier transform,this paper proposes the multiple signal classification（MUSIC） method to estimate the frequency of difference frequency signal.The MUSIC algorithm can make space decomposition of signal and noise for autocorrelation power spectrum in frequency domain by using the orthogonality of signal space and noise space.The simulating and test results show that the proposed method improves much on the precision for single target distance comparing with FFT method.