高精度LFM信号参数估计

解线性调频方法是实际工程中常采用的一种估计LFM信号参数的方法,然而该方法需要对调频斜率在一定范围内搜索,运算量大。针对这个问题本文提出了一种改进算法,首先通过计算LFM信号瞬时自相关的FFT得到调频斜率的估计值,然后在此值附近作小范围精细搜索,从而获得高精度的参数估计值。该方法缩小了搜索的范围,在运算量减少的同时,提高了参数的估计精度。仿真结果表明了此方法的有效性。

Parameter estimation of LFM signal with a high precision

The problem of estimating the parameters of LFM （linear frequency modulation） signals based on de - chirp method is used in engineering implementation frequenty. This method need much computation because it need search chirp rate in some range. In order to avoid its disadvantages, a new estimation algorithm based on dechirp is proposed that decreased the searching range greatly by using signal＇ s autocorrelation. The main characteristics of the proposed algorithm include low computation, easy realization and high precision. Some experimental results are provided to demonstrate the better performance of the estimation method proposed by this paper.