| 摘要 |
PURPOSE:To detect easily collision of signals by superimposing a carrier wave on a leading edge when an output signal is ''1'' and on a tailing edge when the signal is ''0''. CONSTITUTION:A synchronizing signal in synchronizing with the zero cross point of a commercial power supply is outputted from a power synchronizing signal detecting circuit 2. A reception circuit 3 demodulates only a carrier signal from a commercial power supply line. The carrier is transmitted while being superimposed on the front edge when the output signal is ''1'' and on the tailing edge when the signal is ''0'' by a carrier wave superimposing means superimposing the carrrier wave in synchronizing with the synchronizing clock in terms of phase detected by a power supply synchronizing signal detecting circuit 2 of a communication control circuit 4, the commercial power supply line is superimposed in synchronizing clock, and when the carrier wave is detected for both the leading edge and tailing edge of the reception signal, it is discriminated as the collision of two signals. |
