Multiplex communications – Communication over free space – Repeater
Patent
1995-06-14
1997-09-23
Ton, Dang
Multiplex communications
Communication over free space
Repeater
370441, 375205, H04J 1300
Patent
active
056712219
ABSTRACT:
The present invention involves a receiving method and apparatus for use in a communication system wherein a spread-spectrum signal containing information bits is transmitted within an environment tending to produce multipath fading. The receiving apparatus includes a channel estimator which estimates channel coefficients, preferably corresponding to the level of correlation between the various multipath components of the spread-spectrum signal and a cell-correlation signal. A channel selector is configured to select one or more of the multipath components based on the channel coefficients, typically choosing multipath components with the greatest level of correlation, a condition which is indicative of a high signal-to-noise power ratio. The channel selector also identifies time delay values representing the time delay between such selected multipath components, such time delay values being used by a spread-spectrum receiver to identify the selected multipath components for presentation on plural diversity branches. A combiner combines the diversity branches in a predetermined manner, typically by weighted summation using weighting factors produced by the channel selector. A decoder extracts information from the combined signal.
REFERENCES:
patent: 4672658 (1987-06-01), Kavehrad et al.
patent: 4901307 (1990-02-01), Gilhousen et al.
patent: 5081643 (1992-01-01), Schilling
patent: 5093840 (1992-03-01), Schilling
patent: 5103459 (1992-04-01), Gilhousen et al.
patent: 5109390 (1992-04-01), Gilhousen et al.
patent: 5164959 (1992-11-01), Cai et al.
patent: 5166951 (1992-11-01), Schilling
patent: 5179571 (1993-01-01), Schilling
patent: 5179572 (1993-01-01), Schilling
patent: 5185762 (1993-02-01), Schilling
patent: 5228056 (1993-07-01), Schilling
patent: 5412686 (1995-05-01), Ling
patent: 5420850 (1995-05-01), Umeda et al.
patent: 5442625 (1995-08-01), Gitlin et al.
Qualcomm Incorporated, "Most Often Asked Questions about CDMA", Aug. 23, 1991, pp. 1-8.
IEEE Transactions on Communications, "Theory of Spread-Spectrum Communications--A Tutorial", vol. Com. 30, No. 5, May 1982, pp. 855-884.
Proceedings of the IEEE, "Introduction to Spread-Spectrum Antimultipath Techniques and Their Application to Urban Digital Radio", vol. 68, No. 3, Mar. 1980, pp. 328-353.
Communications, "Code Division Multiple Access Beyond the Time Domain" by Fred Baumgartner, Feb. 1990.
Qualcomm, Inc., "CDMA Cellular the Next Generation".
Principles of Communication Systems, "Spread Spectrum Modulation" by H. Taub and Dr. Schilling, Chapter Seventeen, pp. 720-749.
Los Angeles Times, "PacTel Cellular Takes a Gamble on Technology", Business Section, Aug. 26, 1990, pp. D1 and D8.
Mobile Phone News, "Qualcomm, PacTel Complete First CDMA Mobile Call: Questions are Left Unanswered", Nov. 23, 1989, Washington, D.C., vol. 7, No. 24, pp. 1-3.
Industrial Communications, "Nynex Announces CDMA Microcellular System for New York City", Aug. 10, 1990, Washington, D.C., Issue No. 31, pp. 1-2.
Radio Commuications Report, "Nynex Taps Test of CDMA System in New York City", Mar. 26, 1990, p. 4.
Business Week, "Bolting from the Cellular Herd", Aug. 20, 1990, p. 40.
The Wall Street Journal, "AT&T, 2 Bells Plan to Upgrade Cellular Systems", Aug. 2, 1990, p. B2.
Hewlett-Packard Company, "Concepts of CDMA" by Ken Thompson and Dave Whipple, 1993 Wireless Communications Symposium, pp. 22-23.
Global Communications, "Next Wave of Wireless Devices may be CDMA-Base" by Dr. Irwin M. Jacobs, Sep./Oct. 1991, pp. 36-40.
Cellular Business, "The Quest for Spectrum Efficiency" by Dan Sweeney, Jun. 1991, pp. 24-36.
Sharp Kabushiki Kaisha
Sharp Microelectronics Technology Inc.
Ton Dang
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