Broadband power line communication system optimization for integrated system of visible free space optic and broadband power line communication

摘要

Recently the indoor power line has been proposed as a competitive technology for digital systems in homes. Indoor power line integrated with other systems to distributing data inside home, such as visible free space optic (VFSO). Employing visible light generated by white LEDs for indoor optical wireless have been proposed and implemented. Since white-LED is usually distributed over the ceiling for illumination, it is possible to use the ubiquitous power line cables as a communication medium between other fixed network and LED lights. Some works have been done in this area but because power line is an unpleasantly medium in case of noise and multipath distortion the existing systems do not have good quality factor. So considerations of these parameters are very important issue to model the actual system. Hence for high-speed data communication, channel equalization is necessary the optimal equalizer is based on maximum likelihood sequence estimation (MLSE). In this case, a Decision-feedback equalizer (DFE) has been proposed in to limit the effect of ISI produced by multipath propagation in power line channel.This paper attempts to investigate the performance of decision feedback equalizer (DFE) to reducing the effects of impulsive noise and ISI for integrated between BPLC and VFSO, and comparing the result with system which use Orthogonal Frequency Division Multiplexing (OFDM) techniques with Binary Phase Shift Keying (BPSK) sub carriers. It has been observed that in the case of using DFE the multipath effects and bit error rate are reduced. The information that is presented in this thesis could be useful for a optimizing the design of the BPLC systems.