Downlink capacity estimation in a WCDMA cellular network

Analytical characterisation of low constraint delay (LCD) traffic on the uplink in a WCDMA cellular network is a well-understood procedure. However, the problem of downlink capacity estimation is not widely reported in the open literature. In this paper, we provide a framework through which an efficient procedure can be developed for dimensioning mixed LCD traffic on the downlink in a WCDMA cellular network. In particular, we develop a pole condition that can be used to estimate capacity and the Node B power requirements. Unlike previous works, we characterise the out-of-cell to in-cell interference and the path loss observed in each cell through geometric considerations, rather than performing reference simulations. Moreover, we introduce a simple test that determines whether or not the channelisation code requirements can be supported within each cell, following the calculation of the downlink capacity/power requirements.