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The impact of gateway distribution on the system capacity of CDMA mobile satellite systems Liang, Hongyi

Abstract

Recent research indicates that satellite diversity is a practical means of mitigating the effects of satellite fading for Mobile Satellite Systems (MSS) employing CDMA. However, the underlying assumption of such research is that satellite diversity is available all the time, which is not true in reality. We will investigate the impact of improper gateway distribution on the system capacity of MSS. We investigate the principle of distributing the gateways to ensure single and. double satellite service and present some strategies of searching for the optimal gateway distribution for single and double satellite service. To analyze the impact of gateway distributions on the system capacity of MSS, we classify the general mobile terminal environments into five states. By computing the required power margin of each state to reach the same average Bit-Error Rate (BER) and taking the occurrence probability of each state into account, the capacity of a Mobile Satellite System, expressed as the average number of mobile terminals per satellite over the area ranging from South 80° to North 80°, is analytically derived and thoroughly validated by means of computer simulations. After comparing the system capacity of a MSS with improper gateway distributions to that with the optimal gateway distribution, we show that the capacity of a MSS is decreased considerably due to improper gateway distributions. Moreover, the quantitative results indicate that a MSS in a propagation environment of light shadowing suffers more capacity loss due to improper gateway distribution than a MSS in an environment of heavy shadowing.

Item Metadata

Title
The impact of gateway distribution on the system capacity of CDMA mobile satellite systems
Creator
Liang, Hongyi
Publisher
University of British Columbia
Date Issued
1999
Description
Recent research indicates that satellite diversity is a practical means of mitigating the effects of satellite fading for Mobile Satellite Systems (MSS) employing CDMA. However, the underlying assumption of such research is that satellite diversity is available all the time, which is not true in reality. We will investigate the impact of improper gateway distribution on the system capacity of MSS. We investigate the principle of distributing the gateways to ensure single and. double satellite service and present some strategies of searching for the optimal gateway distribution for single and double satellite service. To analyze the impact of gateway distributions on the system capacity of MSS, we classify the general mobile terminal environments into five states. By computing the required power margin of each state to reach the same average Bit-Error Rate (BER) and taking the occurrence probability of each state into account, the capacity of a Mobile Satellite System, expressed as the average number of mobile terminals per satellite over the area ranging from South 80° to North 80°, is analytically derived and thoroughly validated by means of computer simulations. After comparing the system capacity of a MSS with improper gateway distributions to that with the optimal gateway distribution, we show that the capacity of a MSS is decreased considerably due to improper gateway distributions. Moreover, the quantitative results indicate that a MSS in a propagation environment of light shadowing suffers more capacity loss due to improper gateway distribution than a MSS in an environment of heavy shadowing.
Extent
4806554 bytes
Genre
Thesis/Dissertation
Type
Text
File Format
application/pdf
Language
eng
Date Available
2009-06-12
Provider
Vancouver : University of British Columbia Library
Rights
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
DOI
10.14288/1.0065025
URI
http://hdl.handle.net/2429/9102
Degree
Master of Applied Science - MASc
Program
Electrical and Computer Engineering
Affiliation
Applied Science, Faculty of; Electrical and Computer Engineering, Department of
Degree Grantor
University of British Columbia
Graduation Date
1999-05
Campus
UBCV
Scholarly Level
Graduate
Aggregated Source Repository
DSpace

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Rights

For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.