滑跑中的喷气式战斗机的被动声时频特性

为了分析滑跑中的战斗机的被动声信号的时域、频域、时频分布、能量最大值所对应的频率分布等特性，利用自相关方法、功率谱估计、时频分析和能量极大值所对应的频率等分析方法，对战斗机的声信号的时频特性进行描述。通过2个典型声信号的对比分析，发现飞机起飞瞬间的被动声信号是滑跑中的战斗机的被动声信号的一个新的重要特征；其频率分布具有频率成分高、分布范围广等特点。认为将战斗机的2个主要声特征，即CPA时刻和起飞瞬间的被动声特征联合考虑将有助于实现目标的精确定位和追踪。

Passive acoustic features of moving jet plane

The smart mine was used in unattended airfield surveillance t o investigate the features of time domain, frequency domain and time-frequency distributions of the passive acoustic signals of a moving jet plane. The self-c orrelation, power spectrum estimate, spectrogram analysis and frequency distribution according to the maximum energy were performed to depict the featu res of the passive acoustic signals of the moving jet plane. One new imp ortant features of the instant passive signals of jet plane was pound when jet p lane just started to fly through comparing the time-frequency distributions of two typica l p assive acoustic signals,whose range of frequencies is broad and changes sharply. So, it is necessary to consider the passive acousti c features including the CPA instant and the instant flying signal, which is hel pful to achieve the accurate target classification, localization and tracking.