PAPR Reduction in Orthogonal Wavelet Division Multiplexing Using Threshold controlled Tree Pruning

Document Type : Original Article

Authors

1 Dept. of Electronic and Electrical communication Eng., Faculty of Electronic Eng.

2 Dept. of Computer Science and Engineering, Faculty of Electronic Engineering

Abstract

Orthogonal Wavelet Division Multiplexing (OWDM) is one of the multicarrier Modulation techniques. As all multicarrier modulation (MCM) techniques the main problem is the high Peak to Average Power Ratio (PAPR). In this paper a novel PAPR reduction method for OWDM systems is proposed, in which, a full wavelet packet tree is dynamically structured through joining and splitting to achieve a tree with minimum PAPR. Specifically, data symbols with different mappings through different tree structures are threshold controlled in order to concentrate the whole signal power in the most effective ones, and the sequence with smallest PAPR is transmitted. The information about the selected tree is sent as side information similar to techniques such as selective mapping (SLM) in OFDM systems. Although the side information represents some redundancy, the proposed scheme achieves significant reduction in PAPR at the cost of some computational complexity. The simulation results show that the complementary cumulative distribution function (CCDF) of the PAPR with the proposed algorithm shows about a 3 dB improvement over the original OFDM signal.

[1]            J.A.C., Bingham, "Multicarrier Modulation for Data Transmission: An Idea Whose Time has Come ", IEEE communications Magazine, Vol.28, No.5, May 1990, pp. 5-14.
[2]           HAN S.H., LEE J.H.:" A new PTS OFDM scheme with low complexity for PAPR reduction", IEEE Trans. Broadcast., 2006, 52, pp. 77-82.
[3]           HAN S.H., LEE J.H.:" Modified selected mapping scheme for PAPR reduction of coded OFDM signal ", IEEE Trans.Bradcast., 2004, 50, pp.335-341.
[4]           SLIMANE S.B,: " Reducing the Peak-to- Average Power ratio of OFDM signals through precoding", IEEE Trans.Veh.Technology, 2007, 56, pp.686-695.
[5]           CHEN H., LIANG H.: "Combined selective mapping and binary cyclic codes for PAPR reduction in OFDM Systems ", IEEE Trans. Wirel. Commun., 2007, 6, pp.352-3528
[6]           A.,Akansu, P.,Duhamel , X., Lin, and M., De Courville, " Orthogonal  Transmultiplexers  in communications: A Review ", IEEE Transaction on Signal Processing, Vol.46, No.4, April 1998, pp.979 – 995.
[7]           A, Jamin and P. Mahonen, "Wavelet Packet based modulation for wireless communications," wiley wireless communications and Networking journal, vol.5, no. 2, pp.123 – 137, 2005.
[8]           M.Breiling, S.H.Muller, and J.B.Huber, "SLM peak power reduction without explicit side information," IEEE Commun.Lett., vol.5, no.6, pp.239-241, 2001.
[9]           S.H. Han and J. H. Lee, "An overview of Peak to average power ratio reduction techniques for multicarrier transmission," IEEE wireless communications, vol. 12, no. 2, pp. 56-65, 2005.
[10]       A.R.Lindsey , " Wavelet Packet modulation : a generalized method for orthogonally multiplexed  communications," in IEEE 27th southeastern symposium on system Theory,1995, pp.392-396.
[11]       C. Schurgers and M. B. Srivastava, “A systematic approach to peak to average power ratio in ofdm,” in SPIE’s 47th Annual Meeting, San Diego, CA, 2001, pp. 454–464.
[12]       D. Daly, C. Heneghan, A. Fagan, and M. Vetterli, “Optimal wavelet packet modulation under finite complexity constraint,” in Proc. ICASP, vol. 3, 2002, pp. 2789–2792.
[13]       Y. Li and G. Stuber, Ed., Orthogonal Frequency Division Multiplexing for Wireless Communications. Atlanta: Springer, 2006.