Interference suppression by joint demodulation of cochannel signals



Inter-cell cochannel interference (ICCI) is an inherent problem in all cellular systems due the necessity to reuse the same frequencies after a certain reuse distance. In GSM, the fact that the number of nearby cochannel interferers is relatively small leads to a high probability of a dominant interferer (DI). Hence, suppression of DI alone provides substantial capacity improvement for GSM. The paper summarises different aspects of interference suppression by joint demodulation of cochannel signals in the GSM system. The probability of DI is investigated by network simulations. Moreover, receiver algorithms are described and receiver performance analysis is provided. In addition, requirements that the application of the technique poses for the GSM systems are explained.

Key words

Joint detection channel estimation training sequences interference 


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  1. [Abe70]
    K. Abend and B.D. Fritchman, “Statistical Detection for Communication Channels with Intersymbol Interference”, Proc. of IEEE, Vol. 58, No. 5, pp.779–785, May 1970.Google Scholar
  2. [Ant97]
    C. Antón-Haro, J.A.R. Fonollosa and J.R. Fonollosa, “Blind Channel Estimation and Data Detection Using Hidden Markov Models”, IEEE Trans. on Signal Proc., Vol. 45, No. 1, January, 1997, pp.241–246.Google Scholar
  3. [Bea95]
    N. C. Beaulieu et. al, “Estimating the Distribution of a Sum of Independent Lognormal Random Variables”, IEEE Trans. on Comm., Vol. 43, No. 12, December, 1995, pp. 2869–2873Google Scholar
  4. [Ber96]
    R. Berangi, P. Leung, and M. Faulkner, “Cochannel interference cancellation for mobile communications systems”, Proc. IEEE International Conference on Universal Personal Communications (ICUPC), Sep. 29th-Oct. 2nd, Boston, 1995, pp. 443–447.Google Scholar
  5. [Bot95]
    G. Bottomley, K. Jamal, “Adaptive arrays and MLSE equalisation” 45th IEEE Vehicular Technology Conference, Chigaco, 1995.Google Scholar
  6. [Cha66]
    R.W. Chang and J.C. Hancock, “On Receiver Structures for Channels Having Memory”, IEEE Trans. on Inf. Theory, Vol. 12, No. 3, pp. 463–468, Oct. 1996.Google Scholar
  7. [Che92]
    S. Chen and B. Mulgrew, “Overcoming co-channel interference using an adaptive radial basis function equaliser”,Signal Processing, Vol. 28, 1992, Elsevier Science Publishers B.V., pp.91–107.Google Scholar
  8. [Clar78]
    A.P. Clark, J.D. Harvey and J.P. Driscoll, “Near-maximum likelihood detection processes for distorted signals”, The Radio and Electronic Engineer, Vol. 48. No. 6. pp.301–309, June 1978.Google Scholar
  9. [Due88]
    Alexandra Duel-Hallen and Chris Hegaard, “Delayed Decision-Feedback Sequence Estimation”, IEEE Transactions on Communications, Vol. 37, No. 5, pp.428–436, May 1989.CrossRefGoogle Scholar
  10. [Edw96]
    N. Edwardsson, “Studies of Joint Detection-MLSE in the GSM System”, Master’s Thesis, Royal Institute of Technology, IR-SB-EX-9607, Stockholm, Jan. 1996.Google Scholar
  11. [Esc97]
    Marko Escartin and Pekka A. Ranta, “Interference Rejection with a Small Antenna Array at the Mobile Scattering Environment”,proceedings of First IEEE Signal Processing Workshop on Signal Processing Advances in Wireless Communications (SPAWC), La Bastille, Paris, April 16–18th.Google Scholar
  12. [ETSa]
    ETSI STC-SMG11, “AMR-Working assumptions”, Draft 0.0.4., Meeting #2, Sophia Antipolis, April 21–25, 1997.Google Scholar
  13. [ETSb]
    ETSI TC-SMG, “Overall description of the GPRS radio interface; Stage 2”, GSM Recommendations 03.64, v.5.0.0, July 1997.Google Scholar
  14. [ETSc]
    ETSI TC-SMG, GSM Recommendations, Series 5, March 1997.Google Scholar
  15. [Ett76]
    W. van Etten, “Maximum-Likelihood Receiver for Multiple Channel Transmission Systems”, IEEE Trans. on Comm., February 1976, pp. 276–283.Google Scholar
  16. [Eyu86]
    M. Vedat Eyuboglu amd Shadid U.K. Dureshi, “Reduced-State Sequence Estimation with Set partitioning and Decision Feedback”, IEEE Transactions on Communications, Vol. 36, No. 1, pp. 13–20, Jan. 1988.Google Scholar
  17. [Fal93]
    D. D. Falconer, M. Abdulrahman, W. K. Lo, B. R. Petersen and A. U. H. Sheikh, “Advances in Equalization and Diversity fpr Portable Wireless Systems”, Digital Signal Processing, No. 3, pp. 148–162, 1993.Google Scholar
  18. [For72]
    G. David Forney Jr., “Maximum-Likelihood Sequence Estimation of Digital Sequences in the Presence of Intersymbol Interference”, IEEE Trans. on Inf. Theory, Vol. IT-18, No. 3, pp. 363–378, May 1972.Google Scholar
  19. [Gir93]
    K. Giridhar et. al., “Joint Estimation Algorithms for Co-channel Signal Demodulation”, in Proc. IEEE Int. Conf. on Commun. (ICC), Geneva, 1993, pp. 1497–1501.Google Scholar
  20. [How93]
    I. Howitt, “Recent Developments in Applying Neural Nets to Equalization and Interference Rejection”, Virginia Tech’s 3rd Symposium on Wireless Personal Communications, Blacksburg, June 9–11, 1993.Google Scholar
  21. [Karl96]
    J. Karlsson, J. Heinegård, “Interference rejection combining for GSM”, in proc. of 5th IEEE International Conference Universal Personal Communications, Boston, MA,Sept. 29–Oct. 2, pp.433–437.Google Scholar
  22. [Lau86]
    Piere A. Laurent, “Exact and Approximate Construction of Digital Phase Modulations by Superposition of Amplitude Modulated Pulses (AMP)”, IEEE Transactions on Communications, Vol. 34, No. 2, pp.150–160, Feb. 1986.CrossRefMathSciNetGoogle Scholar
  23. [Li95]
    Y. Li, B. Vucetic, and Y. Sato, “Optimum Soft-Output Detection for Channels with Intersymbol Interference”, IEEE Trans. on Inf. Theory, Vol. IT-41, No. 3, pp. 704–713, May 1995.Google Scholar
  24. [Mos96]
    Shimon Moshavi, “Multi-user Detection for DS-CDMA Communications”, IEEE Communications Magazine, Vol. 34, No. 10, Oct. 1996, pp. 124–136.CrossRefGoogle Scholar
  25. [Mou92]
    Michel Mouly, Marie-B. Pautet, “The GSM System for Mobile Communications”,1992.Google Scholar
  26. [Mou94]
    C. Mourot, J. De Vile, R. Hopper, P. Ranta, “The ATDMA equaliser design and implementation”, in proceedings of RACE Mobile Telecommunications Workshop, Amsterdam, May 17–19, 1994.Google Scholar
  27. [Puk97]
    Markku Pukkila and Pekka A. Ranta, “Channel Estimator for Multiple Co-channel Demodulation in TDMA Mobile Systems”, 2nd European Mobile Communications Conference (EMPCC’97), Bonn, Sept 30-Oct 2, 1997.Google Scholar
  28. [Ran95a]
    P.A. Ranta, A Hottinen, Z.C. Honkasalo, “Co-channel interference cancelling receiver for TDMA mobile systems”, in proceedings of IEEE International Conference on Communications (ICC’95), Seattle, 1995, pp.17–21.Google Scholar
  29. [Ran95b]
    P.A. Ranta, Z. Honkasalo and J. Tapaninen, “TDMA Cellular Network Application of an Interference Cancellation Technique”, in proceedings of 1995 IEEE Vehicular Technology Conference (VTC’95), July 25–28 Chicago, Illinois, USA, pp.296–300.Google Scholar
  30. [Ran96]
    P.A. Ranta, A. Lappeteläinen, Z.C. Honkasalo, “Interference cancellation by Joint Detection in Random Frequency Hopping TDMA networks”, in proceedings of IEEE International Conference on Universal Personal communications (ICUPC’96), Sept. 29–Oct. 2, 1996, Cambridge, MA.Google Scholar
  31. [Ran97a]
    Pekka A. Ranta and Antti Lappeteläinen, “Application of dominant interference cancellation in street microcells”, IEEE International Conference on Communications (ICC’97), Montreal, 8–12th June, 1997, pp.17–21.Google Scholar
  32. [Ran97b]
    Pekka A. Ranta, Markku Pukkila, “Recent results of Co-channel Interference Suppression by Joint Detection in GSM”, to be published in 6th International Conference on Advances in Communications and Control, Corfu, Greece, 23–27 June 1997.Google Scholar
  33. [Ran97c]
    Pekka A. Ranta and Marko Escartin, “Dominant interference cancellation by adaptive antennas in GSM”, in proceedings of IEEE International Conference on Personal, Indoor, Mobile Radio Communications, Helsinki, Sept. 1–4, 1997.Google Scholar
  34. [Rob95]
    P. Robertson, E. Villebrun, and P. Hoeher, “A Comparison of Optimal and Sub-Optimal MAP Decoding Algorithms Operating in the Log Domain”, in proceedings of Internatiol Conference on Communications (ICC’95), Seattle, WA, June 18–22, 1995, pp. 1009–1013.Google Scholar
  35. [Ste94]
    B. Steiner and P. Jung, “Optimum and Suboptimum Channel Estimation for the Uplink CDMA Mobile Radio Systems with Joint Detection”, European Transactions on Telecommunications, Vol. 5, No. 1, Jan.–Feb., 1994, pp. 39–50.Google Scholar
  36. [Stu96]
    Gordon Stüber, “Principles of mobile communications”, Kluwer Academic Publishers, p. 665, 1996.Google Scholar
  37. [Ung74]
    Gottfried Ungerboeck, “Adaptive Maximum Likelihood Receiver for Carrier Modulated Data-Transmission Systems”, IEEE Trans. on Commun., Vol. COM-22, No. 5, pp. 624–636, May 1974.Google Scholar
  38. [Wal95]
    S.W. Wales, “Technique for cochannel interference suppression in TDMA mobile systems”, IEE Proc. Commun., Vol. 142, No.2, April, 1995, pp.106–114.CrossRefMathSciNetGoogle Scholar
  39. [Win84]
    J. Winters, “Optimum Combining in Digital Mobile Radio with Cochannel Interference”, IEEE Journal on Selected Areas in Communications, Vol. SAC-2, No. 4, pp. 528–539, July 1984.Google Scholar
  40. [Yos94]
    H. Yoshino, K. Fukawa, H. Suzuki, “Interference Cancelling Equalizer (ICE) for Mobile Communications”, Proc. IEEE Int. Conf. on Commun. (ICC), New Orleans,1994, pp. 1427–1432.Google Scholar

Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  1. 1.Nokia Research CenterUSA

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