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|Title: ||Performance analysis of CDMA based Wireless Local Loop (WLL) Communication, Case of ETC’s implementation in Addis Ababa|
|Authors: ||Getu, Zeleke|
|Advisors: ||Dr. Ing. Hailu Ayele|
|Copyright: ||2007 |
|Date Added: ||18-Oct-2008 |
|Publisher: ||Addis Ababa University|
|Abstract: ||The demand for CDMA –WLL, Wireless Local Loop, Communication system is
higher than wired network. The CDMA–WLL system in Addis Ababa is providing
voice and data communication services. Because of its fast and reliable service,
many customers are looking forward to be connected to the system.
As CDMA’s nature, each CDMA –WLL user generates interference on the other
users (Self jamming). The increasing number of users is going to cause system
capacity limitation, unsatisfactory and degraded service quality , QoS.
Addis Ababa CDMA-WLL system has started service provision with about 31,000
voice and 960 data communication users. As indicated above when the number of
users increases, the service quality started degradation by dropping and blocking
calls from the system with limited capacity allocation.
These problems are results of improper planning and implementation work so
that the system needs more technical solutions to provide better service quality,
QoS and higher system capacity.
To reduce the effect of the mentioned system problems, this thesis explores
different techniques and methodologies. Cell sectoring and power controlling
techniques pointed as the main performance enhancement methods3.
. Using Power control as the main solution, WLL system’s major problems would
be enhanced both in service quality and capacity.
This thesis proposes efficient power control technique based on centralized SIR
balancing algorithm. Performance characteristics, enhanced service quality and
system capacity of the proposed technique are presented.
The study also explains related advantages of signal to interference, SIR, based
power control algorithm which are used to increase network capacity, extend
battery life and improve quality of service.|
|Description: ||A thesis submitted to the school of Graduate studies of Addis Ababa University in partial fulfillment
of the requirements for the degree of
Masters of Science
|Appears in:||Thesis - Computer Engineering |
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