Authors : N.S. Pradeep and M. Balasingh Moses
Abstract: This study proposes a new Scaling Factor (SF) approach for reducing the over estimation of reliability values for Max-Log-MAP (MLMAP) turbo decoding algorithm. Modified Max-Log-MAP (M-MLMAP) algorithm is smeared by fixing an indiscriminate SF for inner decoder S1 and an optimized, adaptive SF for the outer decoder S2. The performance of various scaling factors is compared and optimized scaling factor is obtained which is influenced by Eb/N0 with least Bit Error Rate (BER). Suitable mathematical relationship between scaling factor and Eb/N0 is also given. The effect of the suggested algorithm for a range of system parameters is considered in a systematic fashion, in order to gauge their performance implications. The numerical results show that the proposed M-MLMAP algorithm improves the performance of turbo decoding over Additive White Gaussian Noise (AWGN) and rayleigh fading channels. The proposed M-MLMAP is superior to MLMAP algorithm in both performance and complexity. The performance of the proposed algorithm is also analysed in Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system for suitable applications in WIMAX and LTE.
N.S. Pradeep and M. Balasingh Moses, 2016. Modified Max-Log-MAP Turbo Decoding Algorithm for MIMO-OFDM System. Asian Journal of Information Technology, 15: 1005-1014.