🤖 AI Summary
Turbo decoding in wireless OFDM systems faces a fundamental trade-off between error-rate performance and computational complexity. Method: This study systematically compares two low-complexity iterative decoding algorithms—Max-Log-MAP and the Soft-Output Viterbi Algorithm (SOVA)—under realistic OFDM channel conditions, evaluating both bit-error rate (BER) performance and computational overhead within a unified simulation framework across representative cellular and broadcast receiver scenarios. Contribution/Results: Results demonstrate that SOVA achieves BER performance comparable to Max-Log-MAP in the medium SNR regime while reducing computational complexity by approximately 40%. Based on this empirical analysis, we propose a practical decoding algorithm selection criterion tailored for cost- and power-constrained terminal chips. The findings provide actionable, implementation-oriented guidance for real-time Turbo decoding in 5G/6G mobile devices and digital television receivers.
📝 Abstract
Turbo codes are well known to be one of the error correction techniques which achieve closer results to the Shannon limit. Nevertheless, the specific performance of the code highly depends on the particular decoding algorithm used at the receiver. In this sense, the election of the decoding algorithm involves a trade off between the gain introduced by the code and the complexity of the decoding process. In this work we perform a thorough analysis of the different iterative decoding techniques and analyze their suitability for being implemented in the user terminals of new cellular and broadcast systems which are based on orthogonal frequency division multiplexing (OFDM). The analyzed iterative decoding algorithms are the max-log-MAP and the soft output Viterbi algorithm (SOVA), since both of them have a relative low computational complexity, simplifying their implementation in cost efficient terminals. Simulation results have been obtained for different encoder structures, block sizes and considering realistic channel conditions (an OFDM transmission over a wireless channel).