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In this paper, a widely-linear (WL) technique is applied into an adaptive per-group frequency-domain (PG-FD) semiblind multiuser equaliser. This algorithm is designed for space-frequency block code (SFBC) downlink multiple-input multiple-output (MIMO) multi-carrier code division multiple access (MC-CDMA) with common pilot channel (CPICH) systems and without cyclic-prefix (CP). The update algorithm relies on information from blind and non-blind parts, and the projection on the subspace spanned by the training and the desired user spreading codes matrices. Numerical results illustrate that the proposed adaptive WL PG-FD semiblind multiuser equaliser significantly outperforms and more robust than existing adaptive PG-FD semiblind multiuser and adaptive PG-FD training-based equalisers in fast time varying multipath 3GPP2 MIMO channel model with high mobility.
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Faculty of Engineering and Technology
Mahanakorn University of Technology
M. Q. Nguyen, P. Foortier, S. Roy and J. F. Beaumont, “Physical implementation of a baseband MC-CDMA downlink receiver,” in Proc. NEWCAS, pp. 136-140, 2010.
S. Plass and S. Kaiser, “MC-CDMA versus OFDMA in cellular environment,” in Proc. 13th European Signal Proceeding Conference, September, 2005.
J. C. Guey, M. P. Fitz, M. R. Bell, and W. Y. Kuo, “Signal design for transmitter diversity wireless communication systems over Rayleigh fading channels,” in Proc. Vehicular Technology Conf., , pp. 136-140, 1996.
S. M. Alamouti, “A simple transmit diversity technique for wireless communications mobile system,” Jour. Select Areas in Commun., vol. 16, no. 8, pp. 1451-1458, October 1998.
E. Lindskog and A. Paulraj, “A transmit diversity scheme for channels with intersymbol interference,” in Proc. Int. Conf. on Commun., vol. 1, pp. 307-311, 2000.
M. J. Dehghani, R. Aravind, S. Jam and K. M. Prabhu, “Space-Frequency block coding in OFDM systems,” in Proc. IEEE TENCON, vol. 1, pp. 543-546, November, 2004.
W. G. Jeon, K. H. Chuang and Y. S. Cho, “An equalization technique for orthgonal frequency division multiplexing systems in time-variant multipath channels,” IEEE Trans. On Commun., vol 49, pp. 1185-1191, January 1999.
Y. S. Choil, P. J. Voltz and F. A. Cassara, “On channel estimation and detection for multicarrier signals in fast and selective Rayleigh fading channels,” IEEE Trans. on Signal Commn., vol. 49, pp. 1375-1387, August, 2001.
X. Cai and G. B. Giannkis, “Low complexity ICI suppression for OFDM over time and frequency-selective Rayleigh fading channels,” in Proc Asilomar Conf. Signals, Systems and Computers, November, 2002.
Stamoulis, S. N. Diggavi and N. Al-Dhahir, “Intercarrier interference in MIMO OFDM,” IEEE Trans. on Signal Processing, vol. 50, pp. 2451-2464, October, 2002.
3GPP/3GPP2 25.996 v6.1.0 (2003-09), “Spatial channel model for multiple input multiple output (MIMO) simulations (Release6),” in 3Gpp, Spatial Channel, 2003.
T. Kim and J. G. Andrews, “Optimal pilot-to-data power ratio for MIMO-OFDM,” in Proc. IEEE GLOBECOM, vol. 3, November-December, 2005.
Z. Ding and D. B Ward, “Semi-blind equalization for space time block codes and its ambiguity analysis,” in Proc. of IEEE Int. Conf. Commun., pp. 2357-2361, June 2004.
E. Aktas and U. Mitra, “Semiblind channel estimation for CDMA systems with parallel data and pilot signals,” IEEE Trans. on Commun., vol. 52, No. 7, pp. 1102-1112, July, 2004.
B. Picibono and P. Chevalier, “Widely linear estimation with complex data,” IEEE Trans. on Signal Processing, vol. 43, pp. 2030-2033, August, 1995.
R. Schober, W. H. Gerstacker and L. H. J. Lampe, “A widely linear LMS algorithm for MAI suppression for DS-CDMA,” in Proc. IEEE Int. Conf. on Commun.’ 2003, pp. 1548-1552, December, 2003.
P. J. Schreier, L. L. Scharf and C. T. Mullis, “A unified approach to performance comparisons between linear and widely linear prccessing,” in Proc. IEEE Workshop on Statistical Signal Processing, pp. 105-108, September, 2003.
R. Schober, W. H. Gerstacker and L. H. J. Lampe, “Data aided and blind stochastic gradient algorithms for widely linear MMSE MAI suppression for DS-CDMA,” IEEE Trans. on Signal Commn., vol. 52, no. 3, pp. 746-756, March, 2004.
R. Schober, W. H. Gerstacker and L. H. J. Lampe, “A blind widely linear minimum-output-energy algorithm,” in Proc Wireless Commun. and Networking, pp. 612-617, vol. 1, 2003.
D. Darsena, G. Giacinto, L. Paura and F. Verde, “Widely linear equalization and blind channel identification for interference-contaminated multicarrier systems,” IEEE Trans. on Signal Commn., vol. 53, pp. 1163-1177, 2005.
F. Sterle, “Widely linear MMSE transceiver for MIMO channels,” IEEE Trans. on Signal Processing, vol. 55, no. 8, pp. 4258-4270, August, 2007.
B. Hombs and J. S. Lehnert, “Multiple-access interference suppression for MC-CDMA by frequency-domain oversampling,” IEEE Trans. on Commun., vol. 53, No. 4, pp. 677-686, April, 2005.
G. Foschini and M. Gans, “On limits of wireless communications in fading environment when using multiple antenna,” Wireless Personal Commun., pp. 311-315, March, 1998.
Y. Zhang, W. E. Leithead and D.J. Leith, ”Random scaling of quasi-newton BFGS method to improve the O(N)2-operation approximation of covariance matrix inverse in gaussian process,” in Proc. ISIC, pp. 452-457, 2007.
IEEE802.20 Working Group on Mobile Broadband Wireless Access, “Overview of METRA model for MBWA MIMO channel,” 2003.
J. P. Kermoal, L. Schumacher, K. I. Pedersen and, P. E. Mogensen and F. Frederiksen, “A Stochastic MIMO radio channel model with experimental validation,” IEEE Jour. on Selected Areas in Commun., vol. 20, no. 6, August 2002.
Y. Ishida, “The future of high-speed train,” in Proc. ISADS, pp. 415-418, 2005.
F. Petre, G. Leus and L. Deneire, “Space-time block coding for single- carrier block transmission DS-CDMA downlink,” IEEE Jour. on Selected Areas in Commun., vol. 21, no. 3, April 2003.
T. P. Krauss and M. D. Zoltowski, “Simple MMSE equalizer for CDMA downlink to restore chip sequence: Comparison to zero forcing and RAKE,” in Proc. IEEE ICASSP’2000, pp. 2865-2868, Istanbu, Turkey, 2000.