When communicating with a second wireless station, a first wireless station judges, based on link-related information received form the second wireless station and link-related information extracted from a signal transmitted by a fourth wireless station, whether a transmission link from the third wireless station to the fourth wireless station and a transmission link from the first wireless station to the second wireless station can be concurrently established without interference with each other. If judging affirmatively, the first wireless station transmits a signal to the second wireless station in synchronization with a signal transmitted by the third wireless station to the fourth wireless station. Preferably, when the first wireless station having a concurrent transmission control function communicates with the second wireless station having a interference reduction function, the first wireless station controls the interference reduction function of the second wireless station based on the link-related information received from the second wireless station and interference information, such that the transmission link from the third wireless station to the fourth wireless station and the transmission link from the first wireless station to the second wireless station can be established at the same time without interference with each other. If judging that the concurrent transmission is available, the first wireless station transmits a signal to the second wireless station according to a timing that overlaps transmission of a signal from the third wireless station to the fourth wireless station.