推荐回答（1个）
防止非法用户盗用信道入网。
抗干扰能力强，特别在中转通信系统中可有效地防止干扰信号对中转台的干扰。
小区域频率复用，提高频率的利用率，达到频率共享。
可以实现不同组别的组呼、全呼等选呼功能，操作简单、方便实用。了解亚音频技术在对讲机中的应用，可以更好地发挥它的功能。
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