An Analytical Model of Cell Coverage for Soft Handoffs in Cellular CDMA Systems

In this paper, we present an analytical model to study the soft handoff coverage by evaluating the new call blocking and the handoff call dropping probabilities in a cellular CDMA system. By assuming that the new call generation rate per unit area is uniformly distributed over the service area, enlarging the soft handoff region may increase both the blocking and the dropping probabilities. On the contrary, although shrinking the soft handoff region can reduce the two probabilities, an adverse effect may occur when the new call generation rate per unit area is largely increased. Finally, by fixing the maximum number of mobile calls per cell to a constant, we found out that a slight increase in the soft handoff region may greatly reduce the blocking and the dropping probabilities as well.