Analysis of the Percentage of Outage for Multimedia Services in Cellular Networks

Outage probability has been commonly used as the primal metric to investigate system capacity of cellular networks. Outage probability is a system-level metric that lacks key information with regards to outage performance within the lifetime of a particular session. Analysis based on the satisfied-user criteria has been recently recommended by Universal Mobile Telecommunication Systems (UMTS) where the outage percentage for each individual session is computed for a more genuine estimate of system capacity. In this paper, the session outage performance is modeled as an alternating renewal process with exponential holding times (ARP/E). Estimation of satisfied-user probability resolves to derivation of the total downtime (bad-time) percentage of an ARP/E. An exact formula for the satisfied-user probability is derived for speech services. The ARP/E analysis developed for speech is also employed as an approximation for the satisfied-user probability of WWW browsing users