METHOD AND APPARATUS FOR POWER SUPPLY SYNCHRONIZING COMMUNICATION IN SPREAD SPECTRUM POWER LINE CARRIER

摘要

PURPOSE:To synchronize completely a M series code generated at the transmission side and the reception side by providing a power synchronization clock generating circuit generating two clock pulses synchronously with an AC power supply in phase and having a specific frequency to the transmission and reception sides. CONSTITUTION:The power synchronizing clock generating circuits 17, 20 generate cock pulses CP1, CP2 synchronously with the AC power supply and having frequencies of a multiple of K/2X2N and a multiple of 2N with respect to the power frequency, where N is the maximum period of the M series code and K is an optional integer. M series code generating circuits 18, 21 use the pulse CP1 as a basic clock to generate the M series code whose phase is synchronized with that of the pulse CP2. Then the M series code is used to apply modulation/demodulation of transmission information. Thus, out of synchronism due to the generation of the M series code for transmission/reception based on the zero cross point of the AC power source is prevented.