Pulse or digital communications – Repeaters – Testing
Patent
1995-07-19
1997-10-14
Chin, Stephen
Pulse or digital communications
Repeaters
Testing
375206, H04B 1707
Patent
active
056779305
ABSTRACT:
Methods and systems for receiving signals in spread spectrum communications are described. In CDMA systems, for example, signature sequences used to generate correlations with received signals may not have ideal autocorrelation properties. In such cases, the correlations determined by the receiver may include errors which are propagated through channel tap estimates to the demodulated and decoded information symbols. To reduce or eliminate such self-interference or inter-ray interference, the correlations are decorrelated by, for example, matrix multiplying them with values related to values of the autocorrelation function for the signature sequence of interest.
REFERENCES:
patent: 4630283 (1986-12-01), Schiff
patent: 5048059 (1991-09-01), Dent
patent: 5224122 (1993-06-01), Bruckert
patent: 5237586 (1993-08-01), Bottomley
patent: 5305349 (1994-04-01), Dent
patent: 5329547 (1994-07-01), Ling
patent: 5345468 (1994-09-01), Bi
patent: 5347535 (1994-09-01), Karasawa et al.
patent: 5500856 (1996-03-01), Nagase et al.
patent: 5506861 (1996-04-01), Bottomley
patent: 5572552 (1996-11-01), Dent et al.
"Optimum Multiuser Detection in Single-Path Rayleigh Fading Channels", Zvonar et al., Presented at Twenty-Ninth Allerton Conference on Communication, Control and Computing, pp. 390-399, Oct. 1991.
"On Multiuser Detection in Asynchronous CDMA Flat Rayleigh Fading Channels", Zvonar et al., PIMRC, five pages, 1992.
"A Comparison of Differentially Coherent and Coherent Multiuser Detection With Imperfect Phase Estimates in Rayleigh Fading Channel", Zvonar et al., IT, one page, 1993.
"Adaptive Multiuser Receiver For Fading CDMA Channels With Severe ISI", Zvonar et al., appearing in the Proceedings of Conference on Information Sciences and Systems, six pages, Mar. 1993.
"Joint Signal Detection and Parameter Estimation in Multiuser Communications", Xie, IEEE Transactions on Communications, vol. 41, No. 7, pp. 1208-1216, Aug. 1993.
"A Spread-Spectrum Multiaccess System with Cochannel Interference Cancellation for Multipath Fading Channels", Yoon, IEEE Journal on Selected Areas in Communications, vol. 11, No. 7, pp. 1067-1075, Sep. 1993.
"On Synchronous CDMA for Mobile Communications", Kajiwara, IEEE Globecom., pp. 858-862, 1992.
"Optimum Detection in Asynchronous Multiple-Access Multipath Rayleigh Fading Channels", Zvonar et al., Twenty-Sixth Annual Conference on Info. Sciences and Systems, Princeton Univ., six pges, Mar. 1992.
"Suboptimum Multiuser Detector for Synchronous CDMA Frequency-Selective Rayleigh Fading Channels", Zvonar et al., five pages, CTMC, 1992.
"Coherent and Differentially Coherent Multiuser Detectors for Asynchronous CDMA Frequency-Selective Channels", Zvonar et al., IEEE MILCOM, pp. 0442-0446, 1992.
"Minimum Probability of Error for Asynchronous Gaussian Multiple-Access Channels", Verdu, IEEE Transactions on Information Theory, vol. IT-32, No. 1, pp. 85-96, Jan. 1986.
"Linear Multiuser Detectors for Synchronous Code-Division Multiple-Access Channels", Lupas et al., IEEE Transactions on Information Theory, vol. 35, No. 1, pp. 123-136, Jan. 1989.
"Near-Far Resistance of Multiuser Detectors in Asynchronous Channels", Lupas et al., IEEE Transactions on Communications, vol. 38, No. 4, pp. 496-508, Apr. 1990.
"A Near-Far Resistant Sliding Window Decorrelating Algorithm for Multi-User Detectors in DS-CDMA Systems", Wijayasuriya t al., IEEE Globecom., pp. 1331-1338, 1992.
"Rake Decorrelating Receiver for DS-CDMA Mobile Radio Networks", Wijayasuriya et al., Electronics Letters, vol. 29, No. 4, pp. 395-396, Feb. 1993.
"Rake Decorrelation as an Alternative to Rapid Power Control in DS-CDMA Mobile Radio", Wijayasuriya et al., IEEE, pp. 368-371, 1993.
"A Family of Suboptimum Detectors for Coherent Multiuser Communications", Xie et al., IEEE Journal on Selected Areas in Communications, vol. 8. No. 4, May, 1990.
"Interference Reduction Applied to Channel Estimation in CDMA Systems", J. Thielecke et al., IEEE, pp. 752-756, Mar. 1994.
"New Antimultipath Technique for Spread Spectrum Receivers", R. S. Mowbray et al., Electronic Letters, vol. 29, No. 5, pp. 456-457, Mar. 4, 1993.
"Adaptive Maximum-Likelihood Receiver for Carrier-Modulated Data-Transmission Systems", B. Ungerboeck, IEEE, vol. Comm-22, No. 5, pp. 624-636, May 1974.
International Search Report re PCT/US96/11685 Date of Mailing of International Search Report: Dec. 3, 1996.
Z. Zvonar, "Multiuser Detection and Diversity Combining for Wireless CDMA Systems", Fourth Winlab Workshop on Third Generation Wireless Information Networks, pp. 65-89 (19-20 Oct. 1993).
S. Wijayasuriya et al., "RAKE Decorrelation as an Alternative to Rapid Power Control in DS-CDMA Mobil Radio", 43rd IEEE Vehicular Technology Conference, pp. 368-371 (18-20 May 1993).
A. Duel-Hallen, "Decorrelating Decision-Feedback Multiuser Detector for Synchronous Code-Division Multiple-Access Channel", IEEE Transactions on Communications, vol. 41, No. 2, pp. 285-290 (1993).
Chin Stephen
Ericsson Inc.
Gluck Jeffrey W.
LandOfFree
Method and apparatus for spread spectrum channel estimation does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for spread spectrum channel estimation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for spread spectrum channel estimation will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1560145