Indian Journal of Science and Technology

Abstract

WiMAX is the most popular wireless technology these days for it has high data rates and better performance than other wireless and wired broadband technologies. The performance of WiMAX is severely affected by the multipath fading environment. The efficiency of the WiMAX system can be improved using efficient forward error coding schemes. In this paper a comparison of various FEC schemes such as BCH, RS, LDPC and convolution encoding has been done on two different channels namely-Rayleigh and AWGN. The BER performance of the WiMAX system is further analyzed by utilizing diverse modulation levels over both Rayleigh and AWGN channel. The simulation results show that the best performance is achieved by RS codes and BCH codes followed by LDPC codes and then the convolutional codes. Also, as we vary the code rate of the convolution encoder the BER further degrades. The graphical representations show that the improvement can go as high as 4 dB in some cases in terms of SNR required achieving a particular BER value. The use of RS and BCH encoding schemes will result in better performance in existing WiMAX systems.
Keywords: AWGN, BCH, FEC, LDPC, WiMAX