运动目标的主动声探测脉冲回波信号波形重构

Waveform Reconstruction of Active Acoustic Detection Pulse Echo Signal of Moving Target

摘要:

水下主动声探测是水下目标探测的主要技术之一,其目标回波信号的模拟技术对水下作战防御、声呐和水中兵器以及水下目标探测系统的研制、实战操作训练等多项国防及民用领域具有十分重要的作用。 针对常见的 CW 和 LFM 主动声探测信号,开展了运动目标回波信号波形的重构技术研究。 在捕获得到主动声探测脉冲的条件下,利用“波形存储重发”的基本方法,根据运动目标相对运动速度,重新设置回波信号采样频率,从而实现宽带回波信号(LFM 信号)及窄带回波信号(CW 信号)的多普勒频移模拟。 根据目标回波时延信息,给出了目标回波时延重构模拟方法,并根据不同目标类型和入射方位给出了目标强度参数设置的参考。

关键词:主动声探测;回波模拟;CW 信号;LFM 信号;波形重构

Abstract:

Underwater active acoustic detection is one of the main techniques for underwater target detection. Its target echo signal simulation technology plays an important role in the defense and civil fields of development, combat operation and training of underwater combat defense, sonar, underwater weapon, and underwater target detection system. Aiming at common CW and LFM active acoustic detection signals, the reconstruction technology of moving target’s echo signal waveforms is studied. Under the con- dition that the active acoustic detection pulse is captured, the basic method of “waveform storage retransmission” is used to reset the echo signal sampling frequency according to the relative motion speed of the moving target, thereby the Doppler shift simulation of broadband echo signal (LFM signal) and narrowband echo signal (CW signal) is realized. According to the target echo delay infor- mation, the simulation method of target echo delay reconstruction is given. The reference of target intensity parameter setting is giv- en according to different target types and incident orientations.

Key words:active acoustic detection; echo simulation; CW signal; LFM signal; waveform reconstruction