传统的MUSIC超分辨时延估计技术是直接基于测量数据,其性能往往只对宽带且频谱近似平坦的信号较优,而对窄带信号估计性能较差。针对上述问题,本文通过利用谐波频率估计模型和 DOA(Direction of Arrival)估计模型之间的等价性,将时延估计问题转化为谐波频率估计问题,提出了一种改进SSMUSIC(Signal Subspace Scaled Multiple Signal Classification)超分辨多径时延估计算法。改进后的算法采用平滑的思想和SSMU-SIC算法的思想构造协方差矩阵和MUSIC谱,实现了对多径时延的超分辨估计。仿真表明,该算法能够实现对窄带信号多径时延超分辨估计且具有DP(Direct-Path)不模糊和谱峰陡峭的特点,估计性能优于传统的超分辨算法。
Traditional MUSIC super-resolution time delay estimation technology is based on the direct data and its performance always better on the condition of wideband and approximate flat spectrum and bad on the narrowband signal.Aim at these problems,this paper use the equality of model-based sinusoidal parameter estimation and DOA estimation,then propose an improved SSMUSIC algorithm of super-resolution time delay estimation through transform the problem into problem of parameter estimation of sinusoidal signals.The improved algorithm adopts the smoothing technique and SSMUSIC technique to construct the covariance matrix and MUSIC spectrum and realizes the Super-Resolution Time Delay Estimation in Multipath Environments.The simulations show that improved algorithm has the better performance on the traditional super-resolution algorithm which can realize the Super-Resolution Time Delay Estimation in Multipath Environments of narrowband signals and has the features of DP unambiguity and abrupt spectrum.