基于宽带信号的高精度时差估计算法

时差估计精度直接影响测向精度，传统时差估计算法受到采样时间间隔和解模糊算法的限制，无法进一步提高精度。对于宽带信号，通过时－频关系将时差估计转换为频率估计，继而采用基于时差搜索的离散傅里叶变换算法进行时差估计，其估计精度不受采样时间间隔的限制，能够适应较低信噪比。该算法运算简单，适于工程实现，可以实时进行处理。仿真结果表明，在一定的带宽条件下，该算法能达到较高的测向精度。

High-precision time delay estimation algorithm of wideband signal

The precision of direction finding is affected directly by the precision of time delay estimation . Traditional time delay estimation algorithms are limited by the requirement of unwrapping phase ambiguity and sample interval .So the precision of time delay estimation can not be improved .The wideband signa according to the relationship between time domain and frequency domain ,converts time delay estimation into frequency estimation .Then ,the time delay can be estimated by the discrete Fourier transform based on the search of time delay .The precision of this algorithm is not limited by the sample interval and the algorithm is able to adapt to the low signal‐to‐noise ratio .The algorithm is simple and suitable for engineering implementation .It can be carried out in real time processing .The simulation results show that the algorithm can achieve very high precision of time delay on the condition of certain band width .