| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a power line communication system in which the configuration of modulation circuit is simple, and the circuitry is not required to be changed for every power supply voltage, and which is applicable even to an AC power supply involving voltage variation, such as commercial power supply.SOLUTION: A control signal for controlling a load 1 is transmitted by using a power line 3 for supplying power from an AC power supply E to the load 1. A signal transmitting section 2 transmits the control signal by processing the voltage waveform of the AC power supply E, and a signal receiving section 4 extracts the control signal from the voltage waveform processed in the signal transmitting section 2. A modulation circuit 5 in the signal transmitting section 2 lowers at least one of the positive voltage and negative voltage, so that a certain voltage drop occurs therebetween, and the demodulation circuit 10 of a signal receiving section 4 demodulates the control signal based on the positive and negative voltage difference in the AC voltage.</p> |
