The two transpolar shortwave time signal circuits,Moscow and Irkutsk to the Great Wall Station in Antarctica, are used to study the fading characters for shortwave long circuit.

为了研究过极区的短波长电路的衰落特，极长城站收测莫斯科、依尔库茨克的短波授时台号，并给出各频率对应的衰落深度、衰落率、衰落平时间等参数的统计特征和衰落幅度分布曲线。