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单选

下列叙述中正确的是(23)。

  • A.时分多路复用是将物理信道的总带宽分割成若干个子信道,该物理信道同时传输各子信道的信号
  • B.虚电路传输方式类似于邮政信箱服务,数据报服务类似于长途电话服务
  • C.多路复用的方法中,从性质上来说,频分多路复用较适用于模拟信号传输,而时分多路复用较适用于数据信号传输
  • D.即使采用数字通信方式,也需要同模拟通信方式一样,必须使用调制解调器
试题出自试卷《软件水平考试(中级)网络工程师上午(基础知识)试题模拟试卷20》
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