Reducing Peak-to-Average Power Ratio of a Turbo Coded OFDM

Abstract

Peak to Average Power Ratio (PAPR) is defined as the instantaneous power (maximum value) to the average power ratio. PAPR is considered to be a major problem in OFDM systems. This problem can cause radical unexpected behavior of the signal fluctuation. This fluctuation is constituted by a large number of power states. The enormous number of these states leads to an additional complexity of ADCs and DACs. This research addresses the previous problem in OFDM systems utilizing Turbo Codes.*μ*LaCP technique is employed for the purpose of decreasing PAPR. Moreover, our OFDM system was simulated in the presence of an AWGN channel with four types of codes (without the presence of ADCs and DACs). These were constituted of PCCC (typical and new), SCCC, and Convolutional Codes. Our Turbo Coded OFDM exhibited unchanged BER performance before and after the use of *μ*LaCP technique. This was accomplished by modifying our previous PAPR reduction technique without sacrificing greatly its attributes.

Peak to Average Power Ratio (PAPR) is defined as the instantaneous power (maximum value) to the average power ratio. PAPR is considered to be a major problem in OFDM systems. This problem can cause radical unexpected behavior of the signal fluctuation. This fluctuation is constituted by a large number of power states. The enormous number of these states leads to an additional complexity of ADCs and DACs. This research addresses the previous problem in OFDM systems utilizing Turbo Codes.

Cite this paper

S. Chronopoulos, V. Christofilakis, G. Tatsis and P. Kostarakis, "Reducing Peak-to-Average Power Ratio of a Turbo Coded OFDM,"*Wireless Engineering and Technology*, Vol. 3 No. 4, 2012, pp. 195-202. doi: 10.4236/wet.2012.34028.

S. Chronopoulos, V. Christofilakis, G. Tatsis and P. Kostarakis, "Reducing Peak-to-Average Power Ratio of a Turbo Coded OFDM,"

References

[1] S. K. Chronopoulos, C. Votis, V. Raptis, G. Tatsis and P. Kostarakis, “In Depth Analysis of Noise Effects in Orthogonal Frequency Division Multiplexing Systems, Utilising a Large Number of Subcarriers,” Proceedings of the 7th International Conference of the Balkan Physical Union, Alexandroupolis, 9-13 September 2009, pp. 967-972.
doi:10.1063/1.3322592

[2] G. Tatsis, C. Votis, V. Raptis, V. Christofilakis, S. K. Chronopoulos and P. Kostarakis, “Performance of UWB-Impulse Radio Receiver Based on Matched Filter Implementation with Imperfect Channel Estimation,” Proceedings of the 7th International Conference of the Balkan Physical Union, Alexandroupolis, 9-13 September 2009, pp. 573-578. doi:10.1063/1.3322512

[3] C. Votis and P. Kostarakis, “Design and Analysis of a Multiple-Input Receiver for Mimo Wireless Applications,” International Journal of Communications, Network and System Sciences, Vol. 3, No. 7, 2010, pp. 593-601. doi:10.4236/ijcns.2010.37079

[4] V. Raptis, C. Votis, G. Tatsis, S. K. Chronopoulos, V. Christofilakis and P. Kostarakis, “Active Tuning Antennas for Wireless Communication,” Proceedings of the 7th International Conference of the Balkan Physical Union, Alexandroupolis, 9-13 September 2009, pp. 1058-1062.
doi:10.1063/1.3322310

[5] S. I. Hernandez, “Simulation and Evaluation of a DVB System Using Simulink (Vol. I),” Master Thesis, Linkopings Universitet, Linkoping, 2005.

[6] F. Zbynek and S. Vladimir, “Reduction of PAPR in OFDM by Clipping,” Proceedings of 15th International Czech-Slovak Scientific Conference Radioelektronika, Brno, May 2005, pp. 474-477.

[7] P.-H. Chang, S.-S. Jeng and J.-M. Chen, “Utilizing a Novel Root Companding Transform Technique to Reduce PAPR in OFDM Systems,” International Journal of Communication Systems, Vol. 23, No. 4, 2010, pp. 447-461.

[8] H. Sakran, M. Shokair and A. A. Elazm, “Combined Interleaving and Companding for PAPR Reduction in OFDM Systems,” Progress in Electromagnetics Research C, Vol. 6, 2009, pp. 67-78.

[9] I. I. Al-kebsi, M. Ismail, K. Jumari and T. A. Rahman, “Eliminate the Effects of Clipping Technique on the SER Performance by Recovering the Clipped Part of the OFDM Signal,” International Journal of Computer Science and Network Security (IJCSNS), Vol. 9, No. 7, 2009, pp. 37-45.

[10] S. K. Chronopoulos, G. Tatsis, V. Raptis and P. Kostarakis, “Enhanced PAPR in OFDM without Deteriorating BER Performance,” International Journal of Communications, Network and System Sciences, Vol. 4, No. 3, 2011, pp. 164-169. doi:10.4236/ijcns.2011.43020

[11] S. K. Chronopoulos, G. Tatsis and P. Kostarakis, “Turbo Codes―A New PCCC Design,” Communications and Network, Scientific Research Publishing Inc., Vol. 3, No. 4, Nov. 2011, pp. 229-234. doi:10.4236/cn.2011.34027

[12] S. K. Chronopoulos, G. Tatsis and P. Kostarakis, “Turbo Coded OFDM with Large Number of Subcarriers,” Journal of Signal and Information Processing (JSIP), Vol. 3, No. 2, 2012, in Press.

[13] S. Shah and V. Sinha, “Iterative Decoding vs. Viterbi Decoding: A Comparison,” Proceedings of the 14th National Conference on Communications NCCC 2008, Mumbai, 1-3 February 2008, pp. 491-493.

[14] W. Xie, G.-J. Hu and Q. Deng, “Application of Turbo Codes in Optical OFDM Multimode Fiber Communication System,” Optics Communications, Vol. 281, No. 5, 2008, pp. 1118-1122. doi:10.1016/j.optcom.2007.10.84

[15] I. S. Raad and M. Yakan, “Implementation of a Turbo Codes Test Bed in the Simulink Environment,” Proceedings of the Eighth International Symposium on Signal Processing and Its Applications ISSPA’05, Sydney, 28-31 August 2005, pp. 847-850.
doi:10.1109/ISSPA.2005.1581071

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

[17] S. Choudhury, “Modeling and Simulation of a Turbo Encoder and Decoder for Wireless Communication Systems,” 2002.
http://users.ece.utexas.edu/~bevans/courses/ee382c/projects/spring02/index.html

[18] W. Henkel, G. Taubock, P. Odling, P. O. Borjesson, N. Petersson and A. Johansson “The Cyclic Prefix of OFDM/DMT—An Analysis,” Proceedings of 2002 International Zurich Seminar on Broadband Communications: Access-Transmission-Networking, Zurich, 19-21 February 2002, p. 22. doi:10.1109/IZSBC.2002.991762

[19] B. Muquet, Z. Wang, G. B. Giannakis, M. De Courville and P. Duhamel, “Cyclic Prefixing or Zero Padding for Wireless Multicarrier Transmissions?” IEEE Transactions on Communications, Vol. 50, No. 12, 2002, pp. 2136-2148. doi:10.1109/TCOMM.2002.806518

[20] A. Vallavaraj, B. G. Stewart and D. K. Harrison, “An Evaluation of Modified μ-Law Companding to Reduce the PAPR of OFDM Systems,” AEU—International Journal of Electronics and Communications, Vol. 64, No. 9, 2010, pp. 844-857. doi:10.1016/j.aeue.2009.07.013

[21] P. Robertson, P. Villebrun and P. Hoeher, “A Comparison of Optimal and Sub-Optimal MAP Decoding Algorithms Operating in the Log Domain,” Proceedings of IEEE International Conference on Communications, Seattle, 18-22 June 1995, pp. 1009-1013.
doi:10.1109/ICC.1995.524253

[22] Agilent, “Fundamentals of RF and Microwave Power Measurements (Part 2)—Power Sensors and Instrumentation,” Application Note, 2006, pp. 55-56.

[23] Anritsu, “CCDF Measurements MS269xA—Signal Analyzer,” Application Note, 15 April 2008.

[24] L. Angrisani, A. Langella and M. Vadursi, “New Digital Signal-Processing Approaches for Measuring Power CCDF Curves,” 13th Symposium on Measurements for Research and Industrial Applications, 9th Workshop on ADC Modeling and Testing (TC4), Athens, 2004.

[25] A. Vallavaraj, B. G. Stewart, D. K. Harrison and F. G. McIntosh, “Reduction of Peak to Average Power Ratio of OFDM Signals Using Companding,” Proceedings of the 9th IEEE International Conference on Communications Systems, Singapore, 6-8 September 2004, pp. 160-164.
doi:10.1109/ICCS.2004.1359359

[26] M. F. Sabir, R. Tripathi, B. L. Evans and A. C. Bovik, “A Real-Time Embedded Software Implementation of a Turbo Encoder and Soft Output Viterbi Algorithm Based Turbo Decoder,” Record of the Thirty-Sixth ACSC, Pacific Grove, 3-6 November 2002, pp. 1099-1103.
doi:10.1109/ACSSC.2002.1196954

[27] G. Tatsis, C. Votis, V. Raptis, V. Christofilakis, S. K. Chronopoulos and P. Kostarakis, “Design and Implementation of Ultra-Wideband Impulse Radio Transmitter,” Proceedings of the 7th International Conference of the Balkan Physical Union, Alexandroupolis, 2009, pp. 579-584. doi:10.1063/1.3322513

[28] C. I. Votis, P. Kostarakis and L. P. Ivrissimtzis, “Design and Measurements of A Multiple-Output Transmitter for MIMO Applications,” Journal of Circuits, Systems, and Computers (JCSC), Vol. 20, No. 3, 2011, pp. 515-529.
doi:10.1142/S0218126611007426

[29] V. Raptis, C. Votis, G. Tatsis, S. K. Chronopoulos, V. Christofilakis and P. Kostarakis, “Tuning Techniques for Planar Antennas in Wireless Communication,” Proceedings of the 7th International Conference of the Balkan Physical Union, Alexandroupolis, 2009, pp. 1053-1057.
doi:10.1063/1.3322309

[30] V. N. Christofilakis, A. A. Alexandridis, P. Kostarakis and K. P. Dangakis, “Software Defined Radio Implementation Aspects Related to the ADC Performance,” Proceedings of the 6th International Multiconference on Circuits, Systems, Communications and Computers, Crete, 7-11 July 2002, pp. 3231-3239.