Abstract:

Aiming at the problem of high blocking probability in many handoff strategies, a novel handoff strategy is proposed to improve the performance of mobile communication systems by adopting some delay to the new calls over the handoff calls when there exists one idle channel. The time is shortened in the busy state. The opportunities of the new call and handoff call to occupy channel are increased. The strategy also takes into account the priority of different data types, and only when the data packet in high-priority data queue is empty, the data packets in general data queue can be transmitted. Expression for the dropping probability of handoff calls and the blocking probability of new calls and the dropping probability of data are derived. Through comparison with the channel reservation strategy and movable boundary strategy, it can be proved that the new handoff strategy provides much better performance improvement by reducing the dropping probability and the blocking probability.

Key words: queuing theory;handoff;multi-service;priority;Markov process