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 CN  Vol.5 No.1 , February 2013
Fast Converging Generalized Turbo Decoding Scheme with Enhanced Throughput for Mobile Radio
Abstract: The use of turbo codes enhances the data transmission efficiency and optimizes the performance of a communication system over wireless fading channels. In this paper, we present a brief overview of the various components of the turbo coding scheme, analyze the complexities of the most popular turbo decoding algorithms, and discuss the various implementation methods of the maximum a posteriori (MAP) algorithm. The paper considers the well-known log-MAP decoding algorithm by a linear approximation of the correction function used by the max* operator. We propose a generalized decoding scheme that optimizes the existing MAP algorithm for faster convergence and better throughput on the basis of varying channel conditions. The proposed scheme of decoding reduces complexity and enhances the throughput with only a negligible loss in BER performance.
Cite this paper: A. Kumar Shankhwar, S. Sharma, R. Tripathi, A. Prakash and A. Singh, "Fast Converging Generalized Turbo Decoding Scheme with Enhanced Throughput for Mobile Radio," Communications and Network, Vol. 5 No. 1, 2013, pp. 9-15. doi: 10.4236/cn.2013.51002.
References

[1]   M. Guan and M. Yang, “Comparison and Design of Decoder in B3G Mobile Communication System,” Communications and Network, Vol. 1 No. 1, 2009, pp. 20-24. doi:10.4236/cn.2009.11003

[2]   Y.-N. Lin, W.-W. Hung, W.-C. Lin, T.-J. Chen and E.-H. Lu, “An Efficient Soft-Input Scaling Scheme for Turbo Decoding,” IEEE International Conference on Sensor Networks, Ubiquitous, and Trustworthy Computing, Taichung, 5-7 June 2006, pp. 252-255. doi:10.1109/SUTC.2006.28

[3]   M. C. Valenti and J. Sun, “The UMTS Turbo Code and an Efficient Decoder Implementation Suitable for Software-Defined Radios,” International Journal of Wireless Information Networks, Vol. 8, No. 4, 2001, pp. 203-215. doi:10.1023/A:1017925603986

[4]   A. J. Viterbi, “Error Bounds for Convolutional Codes and an Asymptoticallyoptimum Decoding Algorithm,” IEEE Transactions on Information Theory, Vol. 13, No. 2, 1967, pp. 260-269. doi:10.1109/TIT.1967.1054010

[5]   European Telecommunications Standards Institute, Universal Mobile Telecommunications System (UMTS), “Multiplexing and Channel Coding (FDD),” 3GPP TS 125.212 Version 3.4.0, 2000, pp. 14-20.

[6]   S. Chronopoulos, G. Tatsis and P. Kostarakis, “Turbo Codes—A New PCCC Design,” Communications and Network, Vol. 3 No. 4, 2011, pp. 229-234. doi:10.4236/cn.2011.34027

[7]   S. Rekh, S. S. Rani and A. Shanmugam, “Optimal Choice of Inter Leaver for Turbo Codes,” Academic Open Internet Journal, Vol. 15, 2005.

[8]   S. Shah and V. Sinha, “Iterative Decoding vs. Viterbi Decoding: A Comparison,” Proceedings of the 14th National Conference on Communications NCCC 2008, Mumbai, 17 March 2008, pp. 491-493.

[9]   M. Imani and H. Bakhshi, “Training Based Channel Estimation in MIMO-OFDM Systems,” Communications and Network, Vol. 4, No. 1, 2012, pp. 54-60. doi:10.4236/cn.2012.41008

[10]   Y. Abdelkader and E. Jamal, “Optimal Spacing Design for Pilots in OFDM Systems over Multipath Fading Channels,” Communications and Network, Vol. 2 No. 4, 2010, pp. 221-229. doi:10.4236/cn.2010.24032

[11]   M. Imani and H. Bakhshi, “The Tight Bound for the Number of Pilots in Channel Estimation for OFDM Systems,” Communications and Network, Vol. 4 No. 2, 2012, pp. 146-150. doi:10.4236/cn.2012.42019

[12]   L. R. Bahl, J. Cocke, F. Jelinek and J. Raviv, “Optimaldecoding Oflinear Codes for Minimizing Symbol Error Rate,” IEEE Transactions on Information Theory, Vol. 20, No. 2, 1974, pp. 284-287.

[13]   P. Robertson, P. Hoeher and E. Villebrun, “Optimal and Sub-Optimalmaximum a Posteriori Algorithms Suitable for Turbo Decoding,” European Transactions on Telecommunications, Vol. 8, No. 2, 1997, pp. 119-125. doi:10.1002/ett.4460080202

[14]   A. J. Viterbi, “An Intuitive Justification and a Simplified Implementationof the MAP Decoder for Convolutional Codes,” IEEE Journal on Selected Areas in Communications, Vol. 16, No. 2, 1998, pp. 260-264. doi:10.1109/49.661114

[15]   W. J. Gross and P. G. Gulak, “Simplified MAP lgorithm Suitablefor Implementation of Turbo Decoders,” Electronics Letters, Vol. 34, No. 16, 1998, pp. 1577-1578. doi:10.1049/el:19981120

[16]   B. Classon, K. Blankenship and V. Desai, “Turbo Decoding with the constant-Log-MAP Algorithm,” Proceedings International Symposium on Turbo Codes and Related Topics, Brest, 4-7 September 2000, pp. 467-470.

[17]   J. F. Cheng and T. Ottosson, “Linearly Approximated Log-MAP Algorithms for Turbo Decoding,” IEEE Proceedings of Vehicular Technology Conference (VTC) (Houston, TX), Tokyo, 15-18 May 2000, pp. 2252-2256.

[18]   S. Choudhury, “Modeling and Simulation of a Turbo Encoder and Decoder for Wireless Communication Systems,” UT Austin, 2002.

 
 
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