【摘要】 河南省地震局短波通信台网的工作频率被限制在短波的低频段 ,受干扰严重 ,中心台又位于市中心 ,环境噪声电平很高 ,加之 ,局网内可用的电台大部分发射功率小、抗干扰性能差。这些因素给通信台网的工作频率选择带来困难。为提高区域通信的质量 ,在对短波电离层信道传播特性进行分析的基础上 ,结合本地大气噪声和环境噪声的实际情况 ,对河南省地震局通信网的选频问题进行了研究 ,给出了选频的原则和方法 ,介绍了选频试验的结果和体会更多还原

【Abstract】 The working frequency is restricted to low frequency band for the short- wave communication network of Seismological Bureau of Henan Province.Itis difficult to selectthe working frequency for communication network due to the high environmental noise,low emissive power and low anti- noise feature of communication equipment.Based on the analysis of short- wave transmission specialty in ionosphere and local noise caused by atmosphere and environment,the study on short- wave frequency selection for regional communication station was made.In this paper,the principle and method for frequency selection are given.The result and the experience in frequency selection practice are introduced also.更多还原