The muf and the possible maximum skywave field strength are calculated and are compared with the corresponding groundwave . and the conclusion is that the main propagation mode 200 kilometers on the sea is groundwave and the disturbance of skywave could be omitted 得出天波传播的最高可用频率、可能的最强天波场强，并与相应的地波场强进行了比较，阐明了海上200公里距离上的短波通信中电波主要是以地波的形式传播的，天波对地波通信的多径干扰问题可以忽略的结论。
