Analysis of a CDMA downlink in multipath fading channels

Author

Hai, Wang ; Wiberg, Niclas

Author_Institution

Ericsson (China) Co. Ltd., Beijing, China

Volume

2

fYear

2002

fDate

37316

Firstpage

517

Abstract

This paper deals with the performance analysis of a CDMA downlink in multipath fading channels. An approximate expression for the demodulated signal-to-noise ratio is developed for a conventional RAKE receiver. The expression includes an orthogonality factor that quantifies the performance gain of using orthogonal spreading codes in the presence of a time-dispersive channel. A comparison with simulation results shows that the accuracy of the expression is high in various combinations of desired signal, orthogonal and non-orthogonal intra-cell interference, and AWGN. The numerical results also show that not only the strength of individual rays but also their relative phases and delays determine the value of the orthogonality factor.

Keywords

AWGN; cellular radio; code division multiple access; dispersive channels; fading channels; multipath channels; multiuser channels; radio links; radio receivers; radiofrequency interference; spread spectrum communication; AWGN; CDMA downlink; QPSK; RAKE receiver; SNR; additive white Gaussian noise; approximate expression; base-band discrete-time model; delays; demodulated signal-to-noise ratio; multipath fading channels; nonorthogonal intra-cell interference; orthogonal intra-cell interference; orthogonal spreading codes; orthogonality factor; performance analysis; performance gain; simulation results; time-dispersive channel; AWGN; Delay; Downlink; Fading; Interference; Multiaccess communication; Multipath channels; Performance analysis; Performance gain; Signal to noise ratio;

fLanguage

English

Publisher

ieee

Conference_Titel

Wireless Communications and Networking Conference, 2002. WCNC2002. 2002 IEEE

Print_ISBN

0-7803-7376-6

Type

conf

DOI

10.1109/WCNC.2002.993321

Filename

993321