100kHz地波计算方法比较

Discussion on Prediction of Ground-wave at 100kHz

对于无线电授时、导航来说 ,地球表面大地电特性非常重要 ,可以用地波衰减法测定大地等效电特性。目前有若干种方法可用于计算 1 0 0kHz地波场强衰减和二次相位因子随传播路径的距离、大地电特性和大气折射指数的变化。对几种方法计算的结果和采用的参数作了比较和讨论。结果表明 :对于 1 0 0 0km距离的均光滑的地球表面的地波传播而言 。

The electrical characteristics of the earth surface are very important for radio time service and navigation,and the equivalent ground electrical characteristics can be estimated by the ground wave attenuation method.For 100kHz ground wave propagation the field strength attenuation and second phase factor,which vary with ground electrical characteristics,atmospheric radio refractive index and propagation distance between transmitting and receiving antennas,can be calculated by several different methods.The results and adopted parameters for different calculation methods are compared and discussed in this paper.It is shown that for 100kHz ground wave propagation along the uniform and smooth ground,the calculation results,which are obtained from the method proposed by the Radio Institute of China,coincide best with the Recommeneation ITU R 368 7'Ground wave Propagation Curves for Frequencies between 10kHz and 30MHz'.