APPARATUS AND METHOD FOR MULTICARRIER TRANSMISSION/RECEPTION WITH TRANSMISSION QUALITY EVALUATION

摘要

There is provided a communication network system which can set communication parameters which enable an operation under a maximum possible communication rate in a situation where a transmission path has cyclic noise/impedance fluctuations, without being influenced by such local noise/impedance fluctuations. A transmission/reception apparatus 100 transmits training packets for checking the state of the power line at two distinct points in time. Each time a training packet is received, a transmission/reception apparatus 101 analyzes SNR at each carrier frequency, and stores an SNR evaluation result. The transmission/reception apparatus 101 compares two SNR evaluation results which are obtained through two instances of a channel estimation algorithm, selects an SNR evaluation result which dictates a faster PHY rate, and transmits it to the transmission/reception apparatus 100. The transmission/reception apparatus 100 changes modulation/demodulation rules based on the received SNR analytical result.