The present invention effectively suppresses the level of an interference signal from another radar unit with respect to the level of a received signal of a radar unit, and avoids increasing the measurement time and the number of additional circuits required for the suppression. A first radar transmission unit transmits a first radar transmission signal periodically with a first transmission period under the control of a first transmission code control unit on the basis of a first transmission trigger signal generated after a first delay time from the reception of a predetermined synchronization establishment signal by a first transmission trigger signal generation unit. A second radar transmission unit transmits a second radar transmission signal periodically with a second transmission period under the control of a second transmission code control unit on the basis of a second transmission trigger signal generated after a second delay time from the reception of the synchronization establishment signal by a second transmission trigger signal generation unit. The arrival times of interference signals from the first radar transmission unit and the second radar transmission unit fall within the respective transmission intervals of the second radar transmission signal and the first radar transmission signal according to the first delay time and the second delay time.
