该文在分析各种时延估计方法的优缺点的基础上，研究提高时延估计计算精度的方法。文中提出采用线性调频Ｚ变换的方法来提高时延估计的精度。结合采用广义互相关原理，采用线性调频Ｚ 变换对直升机声音信号进行了仿真计算，在有一定相关噪声的条件下，时延估计误差的方差可以达到５ μｓ 以内，优于其它的时延估计方法的计算结果。反映了该方法是一种较好的方法，具有实际意义。将该方法用于智能雷弹中，可以使雷弹对直升机的声定距误差控制在３０ ％ 以内。 Based on the analysis of the advantages and disadvantages of various time delay estimation methods, this paper studies how to improve the accuracy of time delay estimation. In this paper, the method of linear frequency modulation Z transform is proposed to improve the accuracy of time delay estimation. Combining the principle of generalized cross-correlation, the chirp Z-transform is used to simulate the helicopter sound signal. Under certain relative noise, the variance of the delay estimation error can be less than 5 μs, which is better than other delay estimation methods The calculation results. Reflects the method is a better method, of practical significance. Using this method in the intelligent lightning bomb can make the sounding error of the helicopter to the helicopter within 30%.