Performance of handover priority and queueing systems under different handover request strategies

In a mobile communication system, handover priority schemes and queueing schemes have been proposed to give preference to handovers over new arrivals, because the drop-out of an existing call has more impact on performance than does blocking a new call. The performance of several handover priority schemes are investigated using simulation modelling of both the transmission and traffic processes. In particular, we include results of modelling the GSM priority scheme. The results show that the introduction of queueing and channel reservation schemes improves the drop-out performance greatly and that the priority schemes provide up to 16% further improvement. The effects of propagation based handover strategies on the performance of the priority schemes were also investigated as the delay caused by queueing may not be equally tolerable to different handover strategies