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几种射频通信接收机原理框图及优缺点
优点: 1. 在射频链路进行频带选择,在中频链路进行信道选择 ... 图. 理想混频器 在图中,FIN被设置为基带频率为1 MHz的FBB,FLO被设置为本振频率为500 MHz的FLO。 如果是理想混频器,它将产生一个输出,其中包含两个信号音,频率分别为499 MHz和501 MHz。
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