Discrete multi-tone (DMT) transceiver with dynamic rate adaptive water-filling bit-loading technique for in-home power line communication networks

Abstract

Power line based home networking is an emerging technology that allows consumers, using their existing electrical wiring system, to get their computers and other home-electronics devices communicating among themselves, and also share the Internet bandwidth. Discrete multi-tone (DMT), a variant of OFDM, for wired channels is adopted as a multiplexing technique that has the inherent flexibility to adapt the modulation scheme according to the signal-to-noise ratio (SNR) on each subchannel. The power line channel being a slow time variant channel, sub-channel SNRs may change with time, then the bit and energy distribution may need a corresponding change. Such variation in the bit and energy distributions calls for dynamic bit-loading. We propose the application of a dynamic rate adaptive water filling bit-loading technique in order to increase the transmission rate by changing the subchannel bit-loading according to the estimated channel state information