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A Robust Parametric Technique for Multipath Channel Estimation in the Uplink of a DS-CDMA System

Abstract

The problem of estimating the multipath channel parameters of a new user entering the uplink of an asynchronous direct sequence-code division multiple access (DS-CDMA) system is addressed. The problem is described via a least squares (LS) cost function with a rich structure. This cost function, which is nonlinear with respect to the time delays and linear with respect to the gains of the multipath channel, is proved to be approximately decoupled in terms of the path delays. Due to this structure, an iterative procedure of 1D searches is adequate for time delays estimation. The resulting method is computationally efficient, does not require any specific pilot signal, and performs well for a small number of training symbols. Simulation results show that the proposed technique offers a better estimation accuracy compared to existing related methods, and is robust to multiple access interference.

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References

  1. Proakis JG, Salehi M: Communication Systems Engineering. Prentice-Hall, Upper Saddle River, NJ, USA; 2002.

    MATH  Google Scholar 

  2. Iltis RA, Mailaender L: An adaptive multiuser detector with joint amplitude and delay estimation. IEEE Journal on Selected Areas in Communications 1994,12(5):774-785. 10.1109/49.298051

    Article  Google Scholar 

  3. Madhow U: Blind adaptive interference suppression for the near-far resistant acquisition and demodulation of direct-sequence CDMA signals. IEEE Transactions on Signal Processing 1997,45(1):124-136. 10.1109/78.552211

    Article  Google Scholar 

  4. Logothetis A, Carlemalm C: SAGE algorithms for multipath detection and parameter estimation in asynchronous CDMA systems. IEEE Transactions on Signal Processing 2000,48(11):3162-3174. 10.1109/78.875473

    Article  Google Scholar 

  5. Torlak M, Xu G: Blind multiuser channel estimation in asynchronous CDMA systems. IEEE Transactions on Signal Processing 1997,45(1):137-147. 10.1109/78.552212

    Article  Google Scholar 

  6. Strom EG, Parkvall S, Miller SL, Ottersten BE: Propagation delay estimation in asynchronous direct-sequence code-division multiple access systems. IEEE Transactions on Communications 1996,44(1):84-93. 10.1109/26.476100

    Article  MATH  Google Scholar 

  7. Ostman T, Parkvall S, Ottersten BE: An improved MUSIC algorithm for estimation of time delays in asynchronous DS-CDMA systems. IEEE Transactions on Communications 1999,47(11):1628-1631. 10.1109/26.803496

    Article  Google Scholar 

  8. Petrochilos N, van der Veen A-J: Blind time delay estimation in asynchronous CDMA via subspace intersection and ESPRIT. Proceedings of IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP '01), May 2001, Salt Lake City, Utah, USA 4: 2217-2220.

    Google Scholar 

  9. Ruifeng Z, Zhenhui T: ESPRIT-based delay estimators for DS-CDMA systems. Proceedings of IEEE International Conference on Communications (ICC '00), June 2000, New Orleans, La, USA 3: 1472-1476.

    Article  Google Scholar 

  10. Bensley SE, Aazhang B: Subspace-based channel estimation for code division multiple access communication systems. IEEE Transactions on Communications 1996,44(8):1009-1020. 10.1109/26.535441

    Article  MATH  Google Scholar 

  11. Bensley SE, Aazhang B: Maximum-likelihood synchronization of a single user for code-division multiple-access communication systems. IEEE Transactions on Communications 1998,46(3):392-399. 10.1109/26.662645

    Article  Google Scholar 

  12. Strom EG, Malmsten F: A maximum likelihood approach for estimating DS-CDMA multipath fading channels. IEEE Journal on Selected Areas in Communications 2000,18(1):132-140. 10.1109/49.821727

    Article  Google Scholar 

  13. Tripathi V, Montravadi A, Veeravalli VV: Channel acquisition for wideband CDMA signals. IEEE Journal on Selected Areas in Communications 2000,18(8):1483-1494. 10.1109/49.864012

    Article  Google Scholar 

  14. Ertin E, Mitra U, Siwamogsatham S: Maximum-likelihood-based multipath channel estimation for code-division multiple-access systems. IEEE Transactions on Communications 2001,49(2):290-302. 10.1109/26.905887

    Article  MATH  Google Scholar 

  15. Aktas E, Mitra U: Single-user sparse channel acquisition in multiuser DS-CDMA systems. IEEE Transactions on Communications 2003,51(4):682-693. 10.1109/TCOMM.2003.810842

    Article  MathSciNet  Google Scholar 

  16. D'Amico AA, Mengali U, Morelli M: Channel estimation for the uplink of a DS-CDMA system. IEEE Transactions on Wireless Communications 2003,2(6):1132-1137. 10.1109/TWC.2003.819031

    Article  Google Scholar 

  17. Fessler JA, Hero AO: Space-alternating generalized expectation-maximization algorithm. IEEE Transactions on Signal Processing 1994,42(10):2664-2677. 10.1109/78.324732

    Article  Google Scholar 

  18. Universal Mobile Telecommunications System (UMTS) : Spreading and modulation (FDD). In Technical Specification 3GPP 25.213. ETSI, Sophia-Antipolis, France; June 2005. http://www.3gpp.org

    Google Scholar 

  19. Björck Å: Numerical Methods for Least Squares Problems. SIAM, Philadelphia, Pa, USA; 1996. chapter 9

    Book  MATH  Google Scholar 

  20. Rontogiannis AA, Marava A, Berberidis K, Palicot J: Efficient multipath channel estimation using a semi-blind parametric technique. Proceedings of IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP '03), April 2003, Hong Kong, China 4: 477-480.

    MATH  Google Scholar 

  21. Rontogiannis AA, Berberidis K, Marava A, Palicot J: Efficient semi-blind estimation of multipath channel parameters via a delay decoupling optimization approach. Signal Processing 2005,85(12):2394-2411. 10.1016/j.sigpro.2005.02.018

    Article  MATH  Google Scholar 

  22. Universal Mobile Telecommunications System (UMTS) : Selection procedures for the choice of radio transmission technologies of the UMTS. In Tech. Rep. 3GPP 101.112. ETSI, Sophia-Antipolis, France; April 1998.

    Google Scholar 

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Correspondence to Kostas Berberidis.

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Kekatos, V., Rontogiannis, A.A. & Berberidis, K. A Robust Parametric Technique for Multipath Channel Estimation in the Uplink of a DS-CDMA System. J Wireless Com Network 2006, 047938 (2006). https://doi.org/10.1155/WCN/2006/47938

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