MULTI-CARRIER COMMUNICATION SYSTEM AND MULTI-CARRIER COMMUNICATION METHOD

摘要

A multicarrier communication device most suitable for a network built in a small-scale business or in a household, manufactured at low cost, having a high transmission rate, and resistant to noise. When a QAM encoder (12) outputs DMT modulation/demodulation multicarrier data, LPFs (12a to 12d) cut off the frequency band of each carrier to 1/4. Then an inverse Fourier transforming circuit (13) performs inverse Fourier transform, and a P/S (14) performs serial conversion. An up-sampling circuit (14a) up-samples the serially-converted multicarrier data at a four-time rate to convert the data to multicarrier data the frequency intervals between the carriers of which is 4x.DELTA.f and the frequency band of which is W. The multicarrier data is outputted into a power line (30) through a D/A converter (15), a transmission AMP (16), an LPF (17), and a power line coupling circuit (18).