liu.seSearch for publications in DiVA
Change search
ReferencesLink to record
Permanent link

Direct link
Uplink Load in CDMA Cellular Radio Systems
Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
2005 (English)Doctoral thesis, monograph (Other academic)
Abstract [en]

The uplink of code division multiple access (CDMA) cellular radio systems is often interference limited. The interference originates from many users whose transmission powers are not observable for the system. This thesis introduces uplink load and applies means of explicitly considering the users’ radio environment when approximating and controlling the load.

A desirable property of all cellular radio systems is uplink feasibility, i.e., existence of finite user transmission powers to support the allocated services. Uplink load can be considered as a measure of how far from infeasibility the system is. The performed characterization of uplink load lead to two concrete definitions related to the amount of received and transmitted power, respectively.

An important part of the total load is the intercell load which is caused by users connected to neighboring base stations. If not carefully handled, the intercell load can jeopardize uplink feasibility. Conversely, knowledge of a lower intercell load can be used to increase the resource assignments. A common denominator in all the work in this thesis is that the intercell load is explicitly considered.

When approximating uplink load, a centralized approach is adopted to study information gathered in several base stations. This yields good approximations of the average load. However, centralized approximations can not detect momentarily peaks in the load. A number of resource allocation algorithms making control decisions in the local base stations are proposed based on experience from characterizing uplink load. As the algorithms study the intercell load, yet without measuring the interference power, they are robust in the sense that they will never assign resources yielding an infeasible system.

A straightforward way of controlling the uplink load is to use measurements of the received interference power. This approach, just as the proposed load approximations, can gain from knowing the background noise power. The same framework used for designing robust resource allocation algorithms, is also used for estimating the background noise power.

Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press , 2005. , 168 p.
Linköping Studies in Science and Technology. Dissertations, ISSN 0345-7524 ; 977
Keyword [en]
CDMA, Uplink Load, Radio Resource Management, Automatic Control, Cellular Radio
National Category
Engineering and Technology
URN: urn:nbn:se:liu:diva-16299ISBN: 91-85457-49-3OAI: diva2:133659
Public defence
2005-11-25, Visionen, Hus B, Campus Valla, Linköpings universitet, Linköping, 10:15 (English)
Available from: 2009-01-13 Created: 2009-01-13 Last updated: 2009-05-15Bibliographically approved

Open Access in DiVA

Uplink Load in CDMA Cellular Radio Systems(1207 kB)897 downloads
File information
File name FULLTEXT01.pdfFile size 1207 kBChecksum SHA-512
Type fulltextMimetype application/pdf
Cover(94 kB)40 downloads
File information
File name COVER01.pdfFile size 94 kBChecksum SHA-512
Type coverMimetype application/pdf

Search in DiVA

By author/editor
Geijer Lundin, Erik
By organisation
Automatic ControlThe Institute of Technology
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar
Total: 897 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 239 hits
ReferencesLink to record
Permanent link

Direct link