被动声呐 meaning in Chinese

passive sonar

Study on double - threshold tracks correlation algorithm for active sonar to passive sonar
主被动声呐多目标航迹关联的双门限算法研究
Research on technique of passive sonar target recognition based modulation line spectrum feature extraction
基于调制线谱特征提取的被动声呐目标识别技术研究
The primary tactical employment of the aircraft is through the use of active and passive electronic sensors , the most useful of which is the sonobuoy
在多种搜潜设备中，主动或被动声呐浮标是能够在较大范围水域布防搜潜的主要航空搜潜装备。