【摘 要】
：
在移动通信系统中,为了充分而有效地利用频谱,须要缩窄波道间隔,但由此会出现严重的邻道干扰和互调干扰。本文针对波道间隔缩窄到25KHz 后,提出收发信机设计必须注意的几个问
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在移动通信系统中,为了充分而有效地利用频谱,须要缩窄波道间隔,但由此会出现严重的邻道干扰和互调干扰。本文针对波道间隔缩窄到25KHz 后,提出收发信机设计必须注意的几个问题及其解决办法。分析调制边带和倍频噪声引起的邻道干扰及其计算方法;分析邻道选择性、发射机互调、接收机互调以及它们的计算方法。并以450MHz 频段为例计算了上述各项的干扰电平、提出解决办法及相应的设计指标。
In the mobile communication system, it is necessary to narrow the channel spacing in order to make full and efficient use of the frequency spectrum. However, serious adjacent channel interference and intermodulation interference may occur. In this paper, after narrowing the channel spacing to 25KHz, several problems that must be noticed in the transceiver design and their solutions are proposed. Analysis of modulation sideband and multipath noise caused by adjacent channel interference and its calculation method; Analysis of adjacent channel selectivity, transmitter intermodulation, receiver intermodulation and their calculation method. Taking the 450MHz frequency band as an example, the interference levels of the above items are calculated and the solutions and corresponding design indexes are proposed.
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