Performance analysis of an OFDM broadband power line communication (BPLC)system with multiple receiving antennas

Abstract

Power line networks are an excellent infrastructure for broadband communication, though there exists some technical difficulties as noise, attenuation, multipath scenario etc. are presented in power line system as power lines are not specifically designed for data communication purposes. In this thesis, analytical approach is presented for a broadband power line communication system (BPLC) to evaluate the bit error rate (BER) with different channel models e.g. 4-path model, 15-path model and 5-path model. A broadband power line system is considered using orthogonal FDM (OFDM) modulation and analysis is carried out to find the expression of the signal to noise ratio at the output of a power line communications system with OFDM modulation and demodulation taking into considerations the effect of channel impairments using the three different channel models with single OFDM receiver. Further, analysis is extended to multiple OFDM receivers for the PLC system using space diversity in receiving end. Results are evaluated for different number of OFDM subcarriers and different channel parameters with single receiver and multiple receiver PLC systems. Results are evaluated for a bandwidth of 20 MHz using the channel coefficients for the different path models. It is found that there are significant improvements in BER performance with increase in the number of OFDM subcarrier for a given system bandwidth of 20 MHz. Further it is noticed that there is significant improvement in receiver sensitivity with increase in number of receiver at a given value of OFDM subcarrier N for a particular BER. Finally, the comparison between the power line channel models depicts that 4-path model provides better estimates of channel performance compared to 15-path model and 5-path model.