Volume- 2
Issue- 1
Year- 2014
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Mr. Nilesh B. B. Patil , Prof. Pragnesh Shah
— We expand our recently introduced concept of unique word orthogonal frequency division multiplexing (UW-OFDM). In UW-OFDM the cyclic prefixes (CPs) are replaced by deterministic sequences, the so-called unique words (UWs). The UWs are generated by appropriately loading a set of redundant subcarriers. By that a systematic complex number Reed–Solomon (RS) code construction is introduced in a quite natural way, because an RS code may be defined as the set of vectors, for which a block of successive zeros occurs in the other domain w.r.t. a discrete Fourier transform. (For a fixed block different to zero, i.e., a UW, a coset code of an RS code is generated.)A remaining problem in the original systematic coded UW-OFDM concept is the fact that the redundant subcarrier symbols disproportionately contribute to the mean OFDM symbol energy. In this paper we introduce the concept of non-systematic coded UW-OFDM, where the redundancy is no longer allocated to dedicated subcarriers, but distributed over all subcarriers. We derive optimum complex valued code generator matrices matched to the best linear unbiased estimator (BLUE) and to the linear minimum mean square error (LMMSE) data estimator, respectively. With the help of simulations we highlight the advantageous spectral properties and the superior bit error ratio (BER) performance of non-systematic coded UW-OFDM compared to systematic coded UW-OFDM and to CP-OFDM in additive white Gaussian noise (AWGN ) as well as in frequency selective environments
[1] R. van Nee, R. Prasad, OFDM for Wireless Multimedia Communications, Artech House Publishers, Boston, 2000.
[2] H. Witschnig, T. Mayer, A. Springer, A. Koppler, L. Maurer, M. Huemer, R. Weigel, ”A Different Look on Cyclic Prefix for SC/FDE” In the Proceedings of the 13th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC 2002), Lisbon, Portugal, pp. 824-828, September 2002.
[3] M. Huemer, C. Hofbauer, J.B. Huber, “The Potential of Unique Words in OFDM”, In the Proceedings of the 15th International OFDM-Workshop (InOWo’ 10), Hamburg, Germany, pp. 140 - 144, September 2010.
[4] L. Jingyi, P. Joo, J. Ro, “The effect of filling Unique Words to guard interval for OFDM”, Document IEEE C802.16a-02/87, IEEE 802.16 Broadband Wireless Access Working Group, September 2002.
[5] M. Huemer, H. Witschnig, J. Hausner, ”Unique Word Based Phase Tracking Algorithms for SC/FDE Systems”, In the Proceedings of the IEEE International Conference on Global Communications (GLOBECOM’ 2003), San Francisco, USA, 5 pages, December 2003.
[6] H. Witschnig, Frequency Domain Equalization for Broadband Wireless Communication - With Special Reference to Single Carrier Transmission Based on Known Pilot Sequences, Dissertation, University of Linz, 2003.
[7] G.R. Redinbo, ”Decoding Real Block Codes: Activity Detection, Wiener Estimation”, In the IEEE Transactions on Information Theory, Vol. 46, No. 2, pp. 609-623, March 2000.
[8] J. B. Huber, ”Untersuchung von Blockcodierverfahren bei gedaechtnisbehafteten Kanaelen”, In ntz-Archiv, Bd. 6, pp. 233-241, 1984.
[9] S. Kay, Fundamentals of Statistical Signal Processing: Estimation Theory, Prentice Hall, Rhode Island 1993.
[10] IEEE Std 802.11a-1999, Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications: High-Speed Physical Layer in the 5 GHz Band, 1999.
Electronics & Telecommunication, msbte/ rviot/ses,Kharghar,NaviMumbai,India,7738376827. (e-mail: nileshbarshepatil@gamil.com).
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