Performance evaluation of predictive handoff scheme with channel borrowing

We report a study on a predictive handoff scheme in cellular networks. We present a new channel resource allocation strategy, which combines predictive channel reservation based on real-time positioning of mobile users and dynamic channel borrowing among cells in time of congestion, to provide services to handoff requests with higher priority over new call requests. We also propose a different criterion, threshold time, to improve the accuracy of channel reservation by better determining the right time to send a reservation request, if necessary, for a potential handoff call. Our simulation results indicate that the new scheme outperforms other handoff schemes including guard channel, the original predictive channel reservation, and channel borrowing by significantly reducing the handoff blocking rates with little impact on the throughput of cellular networks. In addition, our data suggest that initiating reservation requests based on an appropriate threshold time introduces fewer false reservations than initiating reservation requests based on a threshold distance.