perimeter miscrophone是什么?
问题描述：
perimeter miscrophone是什么?
In order to keep the tunnels from being detected by the perimeter microphones,they were very deep — about 9 metres (30 ft) below the surface.
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答
perimeter周边; 周围; 边缘
microphone扩音器,麦克风
为了避免隧道被周边的声纳设备捕捉到,它们被挖的很深,大约在地表下9米（30英尺）
perimeter microphones应翻译为周围的声纳设备