Up link Capacity Enhancement Techniques in a CDMA Wireless Local Loop System

El-Dolil, Sami A.; Hassan, Emad S.

doi:10.21608/mjeer.2006.64166

Up link Capacity Enhancement Techniques in a CDMA Wireless Local Loop System

Document Type : Original Article

Authors

Dept. of Electronic and Electrical Communication Eng., Faculty of Electronic Engineering, Menoufya University, EGYPT

10.21608/mjeer.2006.64166

Abstract

This paper proposes two different approaches to increase the uplink capacity of a Code Division Multiple Access Wireless Local Loop (CDMA-WLL) system. The first approach is to synchronize the uplink so that signals transmitted from different subscriber units within the same cell are time aligned at the base station (BS). The theoretical analysis of the potential capacity gain of uplink synchronous CDMA-WLL is presented. The second approach is to investigate the capacity improvement that can be achieved by using adaptive arrays at the BS. An analytical expression which relates the average bit error rate (BER) to the antenna directivity and the propagation environment is derived.

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