Cell-coverage estimation based on duration outage criterion for CDMA cellular systems

Abstract

Previous papers addressing coverage analysis for code-division multiple-access (CDMA) cellular networks have focused on cell expansion from soft handoff or estimation of cell coverage based on an instantaneous outage criterion. Instantaneous outage estimates of cell coverage are a worst case assessment in that the predicted coverage as a function of the number of users is necessarily smaller than the actual coverage. We present the theoretical framework for estimating reverse-link cell coverage based on a duration outage criterion. Our results show that coverage estimates based on duration outage are typically 15%-30% larger than coverage estimates based on instantaneous outage when the correlation distance of the large-scale shadowing environment is small. We compare our theoretical duration outage results of cell coverage with simulated results that considered various large-scale shadowing conditions as well as Rayleigh small-scale fading. The theoretical and simulated coverage results are found to be in very good agreement. The simulations confirm that the presented theoretical duration outage analyses provide accurate and realistic estimates of reverse-link CDMA cell coverage.