INFORMATION CHANGE THE WORLD

International Journal of Information Technology and Computer Science(IJITCS)

ISSN: 2074-9007 (Print), ISSN: 2074-9015 (Online)

Published By: MECS Press

IJITCS Vol.8, No.6, Jun. 2016

Capacity Enhancement by Using a Multi-User Detector on Uplink Synchronous Mode

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Author(s)

Fadoua Thami Alami, Noura Aknin, Najat Erradi, Ahmed El Moussaoui

Index Terms

Uplink Synchronous Transmission Scheme (USTS);Multiple Access Interference (MAI);Uplink orthogonality;channelization code (CH_C);scrambling code (SC_C);multi-user detectors (MUD);interferences cancellation (IC);other cell interferences;uplink capacity

Abstract

The Uplink Synchronous Transmission Scheme [1], is a technique used by operators, that exploit the uplink orthogonality, to reduce multiple access interferences in uplink direction and consequently to increase uplink capacity. The USTS gives better performances when we have an ideal case presented by no channelization code restrictions per scrambling code. In reality, channelization codes are limited. To resolve this problem, several scrambling codes are used to admit more users in the cell. However, the use of different scrambling codes increases the multiple access interference and consequently decreases uplink capacity gain, since signals transmitted by users under different scrambling codes are non-orthogonal. To obtain more performances and therefore to increase the uplink capacity gain, we will study the introduction of a multi-user detector for interferences cancellation, in uplink synchronous mode. For that, two values of interference cancellation efficiency of the multi-user detector are considered. In this study, only the multiple access interference is reduced. To show the effect of other-cell interferences on uplink synchronous mode capacity, two scenarios are considered: an isolated cell and a multiple cell network.

Cite This Paper

Fadoua Thami Alami, Noura Aknin, Najat Erradi, Ahmed El Moussaoui,"Capacity Enhancement by Using a Multi-User Detector on Uplink Synchronous Mode", International Journal of Information Technology and Computer Science(IJITCS), Vol.8, No.6, pp.21-27, 2016. DOI: 10.5815/ijitcs.2016.06.03

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