本文采用修正的周期图法(Welch法)对舰船磁场信号进行了功率谱估计并给出归一化曲线。在此基础上,提取了频域特征量,利用特征频率f_H进行了目标舰船速度的识别研究。计算机仿真表明,正识率可达95％以上。 In this paper, the modified periodic diagram method (Welch method) is used to estimate the power spectrum of the ship’s magnetic field signal and to give the normalized curve. On this basis, the frequency domain feature is extracted and the target ship velocity is identified by using the characteristic frequency f_H. Computer simulation shows that positive recognition rate can reach more than 95%.