基于离散多项式变换的宽带线性调频信号波达方向估计

摘要

为了解决宽带信号处理的问题,研究了一种宽带线性调频( LFM)信号的波达方向(DOA)估计方法.该方法采用离散多项式变换(DPT)将宽带的LFM信号变换成窄带的,经过变换后,即变换为单个正弦信号和新的噪声.这样可将时变的方向向量转化为时不变的方向向量,再采用常规的窄带信号处理方法——多信号分类( MUSIC)算法,对信号的波达方向进行估计.理论分析和仿真结果表明,该方法能够精确地估计信号的波达方向；不仅计算量小,易于实现,而且估计性能好.%To deal with broadband signal processing, a new algorithm for the Direction Of Arrival (DOA) estimation of wideband Linear Frequency Modulation ( LFM) signal was introduced. In this paper, the broadband LFM signal was transformed into a narrowband signal by Discrete Polynomial-phase Transform ( DPT). After that, the wideband LFM signal could be transformed into a single sinusoidal signal and the new noise. And the time-varying direction vector in time domain was changed to the time-invariant vector. Then, the conventional narrow band signal processing method, Multiple Signal - Classification (MUSIC) algorithm, was used to estimate the DOA. The theoretical analysis and simulation results show that the proposed method can accurately estimate DOA of the signal. The scheme is easy to implement with less computation, and it has good estimation performance.