Performance of soft handoff algorithms in various propagation environments

In order to benefit from the advantages of soft handoff, it is important that the handoff parameters be well set. This paper analyzes the sensitivity of the soft handoff percentage to variations in the propagation environment. The sensitivity analysis is then used to design a robust handoff algorithm so as to reduce possible holes in coverage and excessive handoff overhead in an actual system. The effect of such handoff threshold settings on the mean number of active set updates is also analyzed. Sectorized cells are considered and the varied propagation conditions include the relative base station antenna height relative to surrounding buildings, the variance and cross-correlation of shadow fading signals arriving from different sectors and base stations