Novel Orthogonal Codes for Spectrally-Encoded CDMA Systems in Fading Channels

Author

Forouzan, A.R. ; Garth, L.M. ; Moonen, Marc

Author_Institution

Dept. of Electr. Eng. ESAT-SCD, Katholieke Univ. Leuven, Leuven, Belgium

Volume

59

Issue

9

fYear

2011

fDate

9/1/2011 12:00:00 AM

Firstpage

2562

Lastpage

2573

Abstract

Orthogonal spreading codes play an essential role in code-division multiple-access (CDMA) systems by eliminating multiple-access interference (MAI). In this paper, a novel orthogonal spreading code has been proposed for spectrally-encoded (SE) CDMA, a.k.a., spread-time (ST) CDMA with arbitrary pulse shape. It has been shown that it is possible to retain the orthogonality of the code in the presence of tail truncation by time windowing and in a general multipath fading channel in which users experience different frequency selectivity just by modifying the user codewords. Simulation results show that the proposed codes can achieve single user performance when the code length is twice the number of users.

Keywords

channel coding; code division multiple access; fading channels; interference (signal); multipath channels; orthogonal codes; arbitrary pulse shape; fading channels; frequency selectivity; multipath fading channel; multiple-access interference; orthogonal spreading codes; spectrally-encoded CDMA systems; time windowing; Fading; Multiaccess communication; Partitioning algorithms; Receivers; Time domain analysis; Time frequency analysis; Code-division multiple-access; indoor radio communication; interference suppression; orthogonal spreading codes; spectrally-encoded CDMA; spread-time CDMA;

fLanguage

English

Journal_Title

Communications, IEEE Transactions on

Publisher

ieee

ISSN

0090-6778

Type

jour

DOI

10.1109/TCOMM.2011.063011.100278

Filename

5957241