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下列叙述错误的是（)A．高频无线电信号由天线发出后，沿两条路径在空间传播B．微波天线的高度方向

下列叙述错误的是()

A．高频无线电信号由天线发出后，沿两条路径在空间传播

B．微波天线的高度方向性，在地面一般采用广播方式通信

C．人们将小区式移动通信系统叫做蜂窝移动通信系统

D．使用卫星通信时，需要注意它的传输延迟，传输延迟的典型值为540ms

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