| 摘要 |
PURPOSE:To provide a radio communication system which can control the radio signal outputted from a transmitting device in accordance with the distance between the transmitting device and a receiving device. CONSTITUTION:A receiving device 2 connected by radio to a transmitting device 1 is provided with a level detecting circuit 15 which detects the receiving level of the radio signal sent from the device 1, a microcomputer 17 which outputs a level confirming signal to the device 1 in accordance with the detecting level of the circuit 15, a transistor 20, and an LED 18. Meanwhile the device 1 is provided with a PD 8 which receives the level confirming signal from the device 2 and controls the radio signal outputted to the device 2 in accordance with the level confirming signal, a photodetecting amplifier 10, a microcomputer 3, a transistor 7, and an LED 6. In such a constitution, the optimum radio signal is outputted from the device 1 in accordance with the distance between both devices 1 and 2. Then the communication reliability is improved and the lifetime of a battery is increased with its effective application. Furthermore the radio interference is also prevented. |
