TRANSMITTER, RECEIVER, AND CONTROL METHOD
According to an embodiment of the present invention, a transmission device includes: a first modulation unit configured to perform intensity modulation on a control signal for performing management control of communication; a second modulation unit configured to perform phase modulation or frequency modulation on the control signal; a reception modulation scheme acquisition unit configured to acquire a modulation scheme receivable by a receiver receiving the control signal; and a modulation control unit configured to cause the first or second modulation unit to modulate the control signal in accordance with a modulation scheme acquired by the reception modulation scheme acquisition unit.
1 . A transmission device comprising:
a first modulator that performs modulation on a control signal for performing management control of communication;
a second modulator that performs phase modulation or frequency modulation on the control signal;
a reception modulation scheme acquirer that acquires a modulation scheme receivable by a receiver receiving the control signal; and
a modulation controller that causes the first or second modulator to modulate the control signal in accordance with a modulation scheme acquired by the reception modulation scheme acquirer.
2 . The transmission device according to claim 1 , wherein, when the receiver can receive a signal subjected to the phase modulation, the frequency modulation, and the intensity modulation, the second modulator modulates the main signal and the control signal and the first modulator provided at a rear stage of the second modulator modulates a signal for canceling the main signal.
3 . The transmission device according to claim 2 , wherein the second modulator modulates the control signal in addition to the signal for canceling the main signal by the first modulator.
4 . The transmission device according to claim 1 , wherein, when the control signal is transmitted to a first receiver capable of receiving an intensity-modulated signal and the control signal is transmitted to a second receiver capable of receiving a phase-modulated or frequency-modulated signal, the second modulator modulates the main signal and the control signal for the second receiver and the first modulator provided at the rear stage of the second modulator modulation unit modulates a signal for canceling the main signal, a signal for canceling the control signal for the second receiver, and the control signal for the first receiver.
5 . A receiver comprising:
a receiver that receives a control signal for performing management control of communication;
a first demodulator that demodulates an intensity-modulated signal;
a second demodulator that demodulates a phase-modulated or frequency-modulated signal;
a duplicator that duplicates the control signal received by the receiver and output the control signal to the first and second demodulators;
a transmission modulation scheme acquirer that acquires a modulation scheme by which the control signal is modulated by a transmission device transmitting the control signal; and
a demodulation controller that causes the first or second demodulator to demodulate the control signal in accordance with the modulation scheme acquired by the transmission modulation scheme acquirer.
6 . A receiver comprising:
a receiver that receives a control signal for performing management control of communication;
a first demodulator that demodulates an intensity-modulated signal;
a second demodulator that demodulates a phase-modulated or frequency-modulated signal; and
a signal detector that detects a modulation scheme of the control signal received by the receiver and cause the first or second demodulator to demodulate the control signal in accordance with the detected modulation scheme.
7 . (canceled)
8 . (canceled)