Journal ArticleDOI
Increased CDMA system capacity through adaptive cochannel interference regeneration and cancellation
R. S. Mowbray,R. D. Pringle,Peter Grant +2 more
- Vol. 139, Iss: 5, pp 515-524
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TLDR
A technique to exploit this ability to exploit the mean square crosscorrelation levels which exist between the orthogonal codes allocated to each system subscriber in order to gain an increase in the number of multiple access channels available within a particular bandwidth is suggested.Abstract:
Asynchronous code division multiple access (CDMA) systems using digital matched filtering (DMF) reception techniques suffer from poor multiple access spectral efficiency. This is due entirely to the lower bound on the mean square crosscorrelation levels which exist between the orthogonal codes allocated to each system subscriber. This interference can be estimated through channel measurement, and it is then possible to regenerate and subsequently cancel crosscorrelation components from individual interfering channels, thereafter increasing the effective signal-to-interference ratio on the desired channel for a given subscriber activity level. This paper suggests a technique to exploit this ability in order to gain an increase in the number of multiple access channels available within a particular bandwidth. Theoretical analysis of the proposed cancellation scheme shows an upper bound on the spectral efficiency approaching 130% or 1.3 normalised channels per hertz for successive cascaded cancellation stages. Simulation results for CDMA systems show that, for the traditional DMF receiver without dynamic cancellation, the CDMA efficiency is approximately 10% for a bit error rate of 10−4. Analysis is presented for single and two stage cancellation receivers showing 40% and 50% capacity, respectively, for the same error rates derived from a receiver whose complexity is linear in the number of supported active subscribers.read more
Citations
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Journal ArticleDOI
Zero forcing and minimum mean-square-error equalization for multiuser detection in code-division multiple-access channels
Anja Klein,G.K. Kaleh,P.W. Baier +2 more
TL;DR: Four suboptimum detection techniques based on zero forcing and minimum mean-square-error equalization with and without decision feedback (DF) are presented and compared and it is shown that the performance of the MMSE equalizers is better than that of the corresponding ZF equalizers.
Journal ArticleDOI
Interference rejection in digital wireless communications
J.D. Laster,Jeffrey H. Reed +1 more
TL;DR: This overview comprises a literature review of published papers pertaining to single-channel adaptive interference rejection in digital wireless dating primarily from 1980 to the present, focusing on advances not covered by previous overviews.
Journal ArticleDOI
Joint detection with coherent receiver antenna diversity in CDMA mobile radio systems
Peter Jung,Josef Blanz +1 more
TL;DR: In this paper, the application of coherent receiver antenna diversity (CRAD) to the more critical uplink of CDMA mobile radio systems with suboptimum joint detection (JD) techniques is investigated for maximal-ratio combining.
Journal ArticleDOI
Performance of a cellular hybrid C/TDMA mobile radio system applying joint detection and coherent receiver antenna diversity
TL;DR: In this article, a hybrid C/TDMA system using joint detection with coherent receiver antenna diversity (CRAD) at the base station (BS) receiver is proposed, which can flexibly offer voice and data services with different bit rates, soft capacity, inherent frequency and interferer diversity, and high system capacity due to JD.
Book ChapterDOI
DS/CDMA successive interference cancellation
TL;DR: The objective is to underline the need for simplicity and to discuss what is a relatively simple form of multiuser detection (at the base station of a cellular system), successive interference cancellation.
References
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Journal ArticleDOI
Handbook of the Normal Distribution.
Jagdish K. Patel,C. B. Read +1 more
TL;DR: Genesis: an historical background basic properties expansions and algorithms characterizations sampling distributions limit theorems and expansions normal approximations to distributions order statistics from normal samples the bivariate normal distribution Bivariate normal sampling distributions point estimation statistical intervals as discussed by the authors.
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