Combined Beamforming and Channel Estimation in WCDMA Communication Systems
We address the problem of joint beamforming and multipath channel parameters estimation in Wideband Code Division Multiple Access (WCDMA) communication systems that employ Multiple-Access Interference (MAI) suppression techniques in the uplink (from mobile to base station). Most of the existing schemes rely on time multiplex a training sequence with the user data. In WCDMA, the channel parameters can also be estimated from a code multiplexed common pilot channel (CPICH) that could be corrupted by strong interference resulting in a bad estimate. In this paper, we present new methods to combine interference suppression together with channel estimation when using multiple receiving antennas by using adaptive signal processing techniques. Computer simulation is used to compare between the proposed methods and the existing conventional estimation techniques.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1075318Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1927
 T. Ojanpera and R. Prasad, Wideband CDMA for Third Generation Mobile Communications. Boston, London: Artech House, 1998.
 G. L. Turin, “The effects of multipath and fading on the performance of direct sequence CDMA systems," IEEE Trans. Veh. Technol. , vol. VT- 33, pp.213-219, Aug. 1984.
 J. K. Cavers, “An analysis of pilot assisted modulation for Rayleigh fading channels," IEEE Trans. Veh. Technol., vol. 40, pp. 689-693, Nov. 1991.
 S. Buzzi and H. V. Poor, "Channel estimation and multiuser detection in long-code DS/CDMA systems," IEEE Journal Selected Areas in Comm., vol. 19, pp. 1476 - 1487, August 2001.
 Y. Li, L. Cimini, and N. Sollenberger, “Robust channel estimation for OFDM systems with rapid dispersive fading channels," IEEE Trans. Commun., vol. 46, pp. 902-915, July 1998.
 Y. Li, “Pilot-symbol-aided channel estimation for OFDM in wireless systems," IEEE Trans. Veh. Technol., vol. 49, pp. 1207-1215, July 2000.
 Anthony J. Weiss, Benjamin Friedlander, “Channel estimation for DSCDMA downlink with aperiodic spreading codes," IEEE Trans. Commun., vol. COM-47, pp. 1561 - 1569, October 1999.
 M. Madkour, Nermin Mohamed, “A new channel estimation technique for any CDMA-based communications system," the 46th IEEE Mid West Symposium on Circuits and Systems, Cairo, Egypt, Dec. 28-30 2003.
 Stephen E. Bensley, Behnaam Aazhang, “Subspace-based channel estimation for code division multiple access communication systems," IEEE Trans. Commun., vol. COM-44, pp. 1009 - 1020, August 1996.
 G. V. Tsoulos, et al “Low complexity smart antenna methods for third generation W-CDMA systems," IEEE Trans. Veh. Technol., vol. 49, no. 6, pp. 2382-2396, 2000.
 J. C. Liberti and T. S. Rappaport, Smart Antenna for Wireless Communications IS-95 and 3rd Generation CDMA Applications. Englewood Cliffs, NJ: Prentice-Hall, 1999.
 H. Li, T. Liu, “Comparison of beamforming techniques for WCDMA communication systems," IEEE Trans. Veh. Technol., vol. 52, pp. 752- 760, July 2003.
 G. Yue, X. Zhou, and X. Wang, “Performance comparisons of channel estimation techniques in multipath fading CDMA," ," IEEE Trans. Wireless Commun., vol. 3, no. 3, pp. 716-724, May 2004.
 S. Abeta, M. Sawahashi, and F. Adachi, “Performance comparison between time-multiplexed pilot channel and parallel pilot channel for coherent Rake combining in DS-CDMA mobile radio," IEICE Trans. Commun., vol. E81-B, no. 7, pp. 1417-1425, July 1998.
 G. Xue and J. Weng, “Adaptive multistage parallel interference cancellation for CDMA," IEEE J. Select. Areas Commun., vol. 17, pp. 1815-1827, Oct. 1999.
 “Spreading and modulation (FDD)," 3GPP, TS 25.213 V2.0.0, 1999-4, available at http://www.3gpp.org/specs/specs.html