CA2102082A1 - Despreading Technique for CDMA Systems - Google Patents

Despreading Technique for CDMA Systems

Info

Publication number
CA2102082A1
CA2102082A1 CA2102082A CA2102082A CA2102082A1 CA 2102082 A1 CA2102082 A1 CA 2102082A1 CA 2102082 A CA2102082 A CA 2102082A CA 2102082 A CA2102082 A CA 2102082A CA 2102082 A1 CA2102082 A1 CA 2102082A1
Authority
CA
Canada
Prior art keywords
code coefficient
cdma systems
despreading
derived
users
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA2102082A
Other languages
French (fr)
Other versions
CA2102082C (en
Inventor
Qi Bi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
AT&T Corp
Original Assignee
American Telephone and Telegraph Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by American Telephone and Telegraph Co Inc filed Critical American Telephone and Telegraph Co Inc
Publication of CA2102082A1 publication Critical patent/CA2102082A1/en
Application granted granted Critical
Publication of CA2102082C publication Critical patent/CA2102082C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/14—Relay systems
    • H04B7/15—Active relay systems
    • H04B7/204—Multiple access
    • H04B7/216—Code division or spread-spectrum multiple access [CDMA, SSMA]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H04B1/7097—Interference-related aspects
    • H04B1/7103—Interference-related aspects the interference being multiple access interference
    • H04B1/7105—Joint detection techniques, e.g. linear detectors
    • H04B1/71052—Joint detection techniques, e.g. linear detectors using decorrelation matrix
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
    • H04K1/00—Secret communication
    • H04K1/02—Secret communication by adding a second signal to make the desired signal unintelligible

Abstract

Despreading of the received signal in a CDMA system is provided using code coefficient sequences which are derived from those utilized by the system users to encode their respective symbols. Each derived code coefficient sequence is a function of the correlation between a different user's code coefficient sequence and the code coefficient sequences of all other users. Advantageously, this technique substantially reduces interference effects and is suitable for use in the despreader of differentially or nondifferentially coded CDMA systems.
CA002102082A 1992-12-16 1993-10-29 Despreading technique for cdma systems Expired - Fee Related CA2102082C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US991,841 1992-12-16
US07/991,841 US5345468A (en) 1992-12-16 1992-12-16 Despreading technique for CDMA systems

Publications (2)

Publication Number Publication Date
CA2102082A1 true CA2102082A1 (en) 1994-06-17
CA2102082C CA2102082C (en) 1998-02-03

Family

ID=25537635

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002102082A Expired - Fee Related CA2102082C (en) 1992-12-16 1993-10-29 Despreading technique for cdma systems

Country Status (6)

Country Link
US (1) US5345468A (en)
EP (1) EP0602843B1 (en)
JP (1) JP3088227B2 (en)
KR (1) KR100278727B1 (en)
CA (1) CA2102082C (en)
DE (1) DE69330740T2 (en)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5553062A (en) * 1993-04-22 1996-09-03 Interdigital Communication Corporation Spread spectrum CDMA interference canceler system and method
KR100217715B1 (en) * 1993-12-31 1999-09-01 윤종용 Up-link system in ds/cdma
US5617088A (en) * 1994-01-26 1997-04-01 Sony Corporation Sampling frequency converting device and memory address control device
DE69530259T2 (en) * 1994-04-22 2003-12-24 Nippon Telegraph & Telephone METHOD FOR RECEIVING A CODE DIVISION MULTIPLEX SIGNAL
EP0721264B1 (en) * 1994-06-23 2003-11-26 Ntt Mobile Communications Network Inc. Method and device for receiving code-division multiplex signal
US5677930A (en) * 1995-07-19 1997-10-14 Ericsson Inc. Method and apparatus for spread spectrum channel estimation
US5615209A (en) * 1995-07-26 1997-03-25 Ericsson Inc. Method and apparatus for CDMA signal orthogonalization
US6047192A (en) * 1996-05-13 2000-04-04 Ksi Inc. Robust, efficient, localization system
US5790537A (en) * 1996-05-15 1998-08-04 Mcgill University Interference suppression in DS-CDMA systems
US6101178A (en) 1997-07-10 2000-08-08 Ksi Inc. Pseudolite-augmented GPS for locating wireless telephones
US6229857B1 (en) * 1998-06-02 2001-05-08 Intel Corporation Adaptive ingress filtering system
US6577658B1 (en) 1999-09-20 2003-06-10 E20 Corporation, Inc. Method and apparatus for planar index guided vertical cavity surface emitting lasers
JP3514217B2 (en) 2000-06-29 2004-03-31 日本電気株式会社 Turbo decoding method and receiver
DE102005053301B3 (en) * 2005-11-09 2007-02-22 Atmel Germany Gmbh Data symbols detection unit for transmit/receive device, has sequence provisioning unit providing group of sequences, which are stepped higher than sequences in transmission side, where chips of respective sequences store different values

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4885757A (en) * 1987-06-01 1989-12-05 Texas Instruments Incorporated Digital adaptive receiver employing maximum-likelihood sequence estimation with neural networks
US4995104A (en) * 1989-05-08 1991-02-19 At&T Bell Laboratories Interference cancelling circuit and method
US5031173A (en) * 1989-08-15 1991-07-09 Unisys Corporation Decoder for added asynchronous bit sequences
US5099493A (en) * 1990-08-27 1992-03-24 Zeger-Abrams Incorporated Multiple signal receiver for direct sequence, code division multiple access, spread spectrum signals
JPH0779281B2 (en) * 1990-09-21 1995-08-23 日本ビクター株式会社 Spread spectrum modulation demodulator
DE59106942D1 (en) * 1990-11-22 1996-01-04 Ascom Tech Ag Multiple access method and mobile radio system for carrying out the multiple access method.
US5151919A (en) * 1990-12-17 1992-09-29 Ericsson-Ge Mobile Communications Holding Inc. Cdma subtractive demodulation
US5218619A (en) * 1990-12-17 1993-06-08 Ericsson Ge Mobile Communications Holding, Inc. CDMA subtractive demodulation
US5136612A (en) * 1990-12-31 1992-08-04 At&T Bell Laboratories Method and apparatus for reducing effects of multiple access interference in a radio receiver in a code division multiple access communication system
US5177766A (en) * 1991-06-03 1993-01-05 Spectralink Corporation Digital clock timing generation in a spread-spectrum digital communication system
US5237586A (en) * 1992-03-25 1993-08-17 Ericsson-Ge Mobile Communications Holding, Inc. Rake receiver with selective ray combining
US5295153A (en) * 1992-04-13 1994-03-15 Telefonaktiebolaget L M Ericsson CDMA frequency allocation

Also Published As

Publication number Publication date
KR100278727B1 (en) 2001-01-15
EP0602843B1 (en) 2001-09-12
EP0602843A2 (en) 1994-06-22
JP3088227B2 (en) 2000-09-18
KR940017331A (en) 1994-07-26
DE69330740D1 (en) 2001-10-18
EP0602843A3 (en) 1995-02-08
JPH06261021A (en) 1994-09-16
DE69330740T2 (en) 2002-07-04
US5345468A (en) 1994-09-06
CA2102082C (en) 1998-02-03

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Legal Events

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EEER Examination request
MKLA Lapsed
MKLA Lapsed

Effective date: 20091029