Uplink Load and Link Budget with Stochastic Noise Rise Levels in CDMA Cellular Systems
2005 (English)In: Proceedings of Radiovetenskap och Kommunikation 2005, 2005, 491- p.Conference paper (Other academic)
The limiting factor in the uplink of all CDMA cellular systems is the relation between uplink noise rise and intended coverage. In link budgets, noise rise is usually simply handled as a constant contribution to the background noise in logarithmic scale, often referred to as interference margin. In practice, however, it is not constant. We model the uplink noise rise as a lognormal distribution, and investigate the impact to link budgets. Simulations and numerical calculations show that the uplink noise rise variance does not critically affect the uplink capacity and coverage. System feasibility and its relation to the uplink load is also discussed. It is shown that approximative load expressions provides an upper bound on the uplink load and therefore they can be used to imply system feasibility. Furthermore, the uplink load expressions provide accurate approximations of the load given that the load is within the practical limits given by the link budgets.
Place, publisher, year, edition, pages
2005. 491- p.
Link budget, Noise rise variance, Maximum noise rise, System load
Engineering and Technology Control Engineering
IdentifiersURN: urn:nbn:se:liu:diva-29719Local ID: 15113OAI: oai:DiVA.org:liu-29719DiVA: diva2:250536
Radiovetenskap och Kommunikation, Linköping, Sweden, June, 2005