IU-Journal of Electrical & Electronics Engineering 1303-0914 İstanbul University-Cerrahpasa Engineering Mühendislik Performance of Bit Level Decoding Algorithms for Binary LTE Turbo Codes with Early Stopping Beeharry Yogesh University of Mauritus Fowdur Tulsi Pawan University of Mauritius Soyjaudah Krishnaraj M. S University of Mauritius 07 27 2017 17 2 3399 3415 01 16 2017 Copyright © 2001, IU-Journal of Electrical & Electronics Engineering 2001 IU-Journal of Electrical & Electronics Engineering

Turbo codes apply aniterative message passing mechanism between two concatenated decoders. Theirastounding performance has led to their widespread adoption in severalcommunication standards such as Long Term Evolution (LTE), and Code Divisionfor Multiple Access (CDMA) 2000. This paper gives an overview of three bit-leveldecoding Max-Log-MAP algorithms with Sign Difference Ratio (SDR)-based earlystopping that can be used in LTE Turbo Codes. A detailed computationalcomplexity analysis is given for the three methods. It is observed that thecomplexity of the decoding methods decrease significantly as the Eb/N0increases when SDR is used. Moreover, the Bit Error Rate (BER) performance ofthe methods was also assessed and compared for different modulation schemes.Results show that the different methods perform differently in the waterfalland error-floor regions with different modulation schemes. Moreover, thecomputational complexity analysis show that Method 2 requires fewer overallnumber of computations compared to Methods 1 and 3.

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