Patent ID: 8432839

Claim:
A bidirectional wireless communication system comprising: a first wireless communication apparatus configured to multiplex a modulated signal obtained by modulating an input signal by a reference carrier signal having a predetermined carrier frequency, and wirelessly transmit a resultant transmission signal; and a second wireless communication apparatus, including: a reception section configured to receive the transmission signal wirelessly transmitted by the first wireless communication apparatus and produce therefrom a reception signal, a first oscillator configured to produce a signal having a free-running oscillation frequency upon which reception processing is based, where the reception signal is injected into the first oscillator, a control unit configured to vary the free-running oscillation frequency of the first oscillator, and a frequency locking detection unit configured to detect whether the free-running oscillation frequency of the signal of the first oscillator is in a frequency range in which injection locking with the carrier frequency of the reception signal will occur such that frequency-locking with the carrier frequency of the reception signal results; wherein, when the frequency locking detection unit detects that the free-running oscillation frequency of the signal of the first oscillator is in a frequency range in which injection locking with the carrier frequency of the reception signal will occur such that frequency-locking with the carrier frequency of the reception signal results, the second wireless communication apparatus transmits a communication enable signal to the first wireless communication apparatus.