Disclosed is radar wave detection and DFS (dynamic frequency selection) with high efficiency while considering, for instance, the power consumption of each communication station within an autonomous distributed network. At least one communication station runs in an interference avoidance operation mode, operates a radar wave detection section, and fulfills the obligation to issue instructions for radar wave detection and DFS for an approximately predetermined period of time. After the lapse of the approximately predetermined period of time, another communication station switches to the interference avoidance operation mode and assumes the obligation to issue instructions for radar wave detection and DFS. In other words, two or more communication stations sequentially run in the interference avoidance operation mode in a time sharing manner. Therefore, the average power consumption of the communication stations decreases.