One of the plurality of first slave receiving apparatuses which serves as a reference first slave receiving apparatus repeatedly transmits a wireless control signal for controlling synchronization between a first receiving apparatus segment and a second receiving apparatus segment. One of the plurality of second slave receiving apparatuses which serves as a reference second slave receiving apparatus transmits a reference timing signal for performing synchronization in the second receiving apparatus segment including the reference second slave receiving apparatus to the second master receiving apparatus in synchronization with the wireless control signal. The second master receiving apparatus transmits a synchronization timing signal for performing synchronization in the second receiving apparatus segment including the second master receiving apparatus to another one of the plurality of second slave receiving apparatuses in the second receiving apparatus segment including the second master receiving apparatus, in response to the reference timing signal.