被动式

zhǔ dòng shì hé bèi dòng shì jiāo tì gōng zuò

主动式和被动式交替工作。

The active and passive modes are alternatively implemented.

jiàn chuán fú shè zào shēng shì bèi dòng shì shuǐ shēng tàn cè shè bèi de xìn xī yuán

舰船辐射噪声是被动式水声探测设备的信息源。

Ship-radiated noise within quite a broad frequency range is the only information source of passive acoustic detection.