Performance of low-complexity channel coding and diversity for spread spectrum in indoor, wireless communication

The application of selection diversity in conjunction with simple channel coding is considered for a multiuser, slowly fading, Spread-Spectrum Multiple Access (SSMA), digital radio system. For the most part, the index of performance for our study is the average bit error probability; we also give so...

Full description

Saved in:
Bibliographic Details
Published in:AT&T Technical Journal Vol. 64; no. 8; pp. 1927 - 1965
Main Authors: Kavehrad, M., McLane, P. J.
Format: Journal Article
Language:English
Published: Oxford, UK AT&T 01.10.1985
Blackwell Publishing Ltd
American Telephone and Telegraph
Subjects:
ISSN:8756-2324, 1538-7305
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The application of selection diversity in conjunction with simple channel coding is considered for a multiuser, slowly fading, Spread-Spectrum Multiple Access (SSMA), digital radio system. For the most part, the index of performance for our study is the average bit error probability; we also give some consideration to multipath outage as a performance measure. All subscribers are assumed to communicate to a central station; that is, a star network architecture is assumed. Average power control is also assumed. The average mentioned in this context includes averaging over the channel fading statistics. The modulation is direct-sequence, spread-spectrum, binary phase-shift keying. We assume perfect timing and carrier recovery in our coherent receiver, and a slowly varying, Rayleigh fading, discrete multipath model is used. Previous analyses have found that SSMA can tolerate few simultaneous users for fading radio channels. We find that the combination of spread-spectrum modulation with low-complexity diversity and/or channel coding can restore fading-channel user levels to an acceptable figure. In addition, selection diversity plus channel coding is more effective than either method by itself. Finally, it turns out that SSMA is less sensitive to a change in the value of delay spread of a fading channel than, say, time-division multiple access. The method of moments is used to accurately assess the system error probability. Using this technique, we also assess the accuracy of assuming that the multiuser interference has a Gaussian distribution, which allows it to be analyzed by a simple method. Using this assumption, we compare selection diversity plus channel coding with the maximal-ratio-combining technique for diversity reception. Except for a high order of diversity, the former is more efficient and is always less complex than the latter.
Bibliography:ark:/67375/WNG-08FZVZHN-J
istex:79C10F07735FCCEE6400357AE5E6A85B063B1117
ArticleID:BLTJ42
Queen's University, Kingston, Canada.
B.S. (Electrical Engineering), 1973, Tehran Polytechnic Institute; M.S. (Electrical Engineering), 1975, Worcester Polytechnic Institute; Ph.D. (Electrical Engineering), 1977, Polytechnic Institute of New York; Fairchild Industries, 1977–1978; GTE, 1978–1981; on the faculty of Northeastern University, 1981–1984; AT&T Bell Laboratories, 1981—.
B.A.Sc., 1965, University of British Columbia; M.S.E.E., 1966, University of Pennsylvania; Ph.D., 1969, University of Toronto; Queen's University, 1969—.
Peter J. McLane
Mohsen Kavehrad
AT&T Bell Laboratories.
ISSN:8756-2324
1538-7305
DOI:10.1002/j.1538-7305.1985.tb00042.x