NOISE FILTER AND PLC MODEM USING THE NOISE FILTER

摘要

PROBLEM TO BE SOLVED: To construct a noise filter which suppresses common mode noise and normal mode noise and can transmit a signal and further to construct a PLC modem excellent in a noise suppression characteristic by using the noise filter.;SOLUTION: This PLC modem has a common mode choke coil 8 consisting of two coils 8b and 8c wound around a magnetic core 8a and a magnetic core 8a, and capacitors 9 and 10 connected serially to the respective coils 8b and 8c, respectively. Serial tuning circuits 11 and 12 consisting of the coils 8b and 8c and the capacitors 9 and 10 are tuned to a prescribed frequency, parallel tuning circuits 6 and 7 for tuning to the prescribed frequency are respectively provided with at least one of the preceding stage side and the subsequent stage of the serial tuning circuits 11 and 12, and the parallel tuning circuits 6 and 7 are connected between the two serial tuning circuits 11 and 12.;COPYRIGHT: (C)2004,JPO&NCIPI