Study on the coexistence of two types of PLCs in HF Band

HF-band power line communication was deregulated in October, 2006 in Japan. There are two types of PLCs. First type of PLC (full tone PLC) uses all of HF-band (2-30MHz). Second type of PLC (dispersed tone PLC) uses dispersed tone modulation using only 2-9MHz of the HF-band. These two PLCs constitute home network in same power line. We investigate interference and coexistence of the two types of PLCs. We propose using only one band elimination filter to solve this interference problem. The filter is inserted into between the master of FT-PLC modem and the power line to control the learning function of FT-PLC modems. Experimental result shows packet losses of DT-PLC are diminished with throughput down of FT-PLC.