Teletraffic evaluation between a switch and base stations in cellular systems with multiple-connection capability for soft handoff

To implement soft handoff in mobile communication systems that employ code division multiple access (CDMA), it is necessary to distribute the communication data to the multiple base stations simultaneously. For that reason, when soft handoff is performed with the same amount of communication line resources as hard handoff, the call blocking probability is higher than for hard handoff. We therefore evaluate the traffic characteristics for the various multi-connection line set-up methods, which include immediate call processing, a simple queuing processing, and a modified queuing processing to give a priority to fast-moving calls, by means of a computer simulation. The evaluation results show that the probability of forced termination at handoff can be reduced by employing a queuing scheme at the time of multi-connection line setup and that the probability of call termination can be further reduced by giving fast-moving calls priority in the allocation of multi-connection lines.