Fairness Aware Resource Allocation in Downlink MIMO-OFDMA System using NSGA-II

Abstract

Resource allocation is a very important factor in wireless communication systems due the limited radio resources like subchannels and power. Resource allocation is carried out with MIMO and OFDMA combination to combine the benefits of both the schemes. Multiple Input and Multiple Output (MIMO) scheme is used to increase the data rate and spectral efficiency in wireless communication system. Singular Value Decomposition (SVD) converts MIMO channels to many Single Input Single Output channels. Subchannels and bits can be allocated jointly in MIMO-OFDMA systems. Subchannel and bits allocation is handled by Non-dominated Sorting Genetic Algorithm (NSGA)-II in downlink of MIMO-OFDMA system. Capacity maximization and overall transmit power reduction and considering fairness among users are the main objectives in this work. Performance analysis is done with and without considering fairness for SNR values 4.6 dB and 24.6 dB respectively. Simulation results reveal that fairness is achieved at the cost of reduction in capacity.