插值方法在TDOA估计中的研究与应用

摘要

The cross correlation method is one of the most classical methods in TDOA time delay estimation,and the maximum precision of time delay estimation is the sampling period.In order to improve the accuracy of the estimation to the sub sampling level,the original signal data is preprocessed by the interpolation.Thus the sampling rate of the system can be improved indirectly.On this basis,the generalized cross correlation and polynomial fitting are used to estimate the time delay and try to improve the maximum precision of time delay estimation.Matlab simulation and measured data analysis show that the interpolation of data preprocessing can greatly improve the accuracy of time delay estimation,obviously converge the accumulated error of time delay estimation and the algorithm has low complexity,so it is easy to be used in the engineering measurement.%TDOA时延估计中,互相关法是最经典方法之一,其所能估计时延的最大精度为系统采样周期.为了将估算精度推进到亚采样周期级别,对原始信号数据进行点内插值预处理,通过算法间接实现提高系统采样率,在此基础上,运用广义互相关及多项式拟合对时延进行估计,尝试提升时延估计的最大精度.通过Matlab仿真及实测数据分析,结果表明,在数据预处理中进行插值处理,可大大提升时延估算精度,时延估算累计误差能够明显收敛,且该算法复杂度低,易于投入工程实测中使用.