WiMAX physical layer optimization by implementing SOVA Decoding algorithm

Turbo code provides relatively better performance as compare to convolution codes at lower Signal to Noise Ratio. Turbo code offers an outstanding coding gain very close to Shannon limit over an AWGN channel to achieve maximum throughput particularly for WiMAX application. The objective of this paper is to Study the Mobile WiMAX system performance by implementing the turbo codes using Soft Output Viterbi Algorithm (SOVA). Turbo decoder is optimized by modifying the SOVA that contributed to the system performance optimization. For different transmission conditions, BER performance has been simulated and compared to the conventional Log-MAP decoding algorithm. The performance of mobile WiMAX system has also been tested for the effect of various Decoding algorithms, Frame size and Code rates.

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