| 摘要 |
PURPOSE:To reduce the power consumption by devising the equipment in which the intensity of an optical signal sent from one communication equipment is decreased only when the reception intensity of an optical signal sent from one communication equipment is larger when other communication equipment receives the signal and the transmission state between the two communication equipments is excellent. CONSTITUTION:A photodiode 38 of a receiver RB of a base unit BU receives an optical signal sent from an LED 20 of a transmitter TP of a portable unit PU. A signal demodulated by a demodulator 41 includes a voice signal and a reference signal for checking the transmission state and the propriety of the transmission state is discriminated from the state of the reference signal sent from a control signal generator 37. When the transmission state is excellent, a transmission intensity control signal in response to the intensity of the signal detected by a signal intensity detector 42 is outputted from the control signal generator 37. That is, when the signal intensity in this case is large, the transmission intensity control signal to control the radiated intensity of the LED 20 of the transmitter TP of the portable unit PU to a small value is outputted. Thus, the power consumption over a required value is suppressed. |
