Dynamically adaptive channel reservation scheme in cellular networks

In personal communications networks (PCN) supporting network-wide handoffs, new and handoff requests compete for connection resources in both the mobile and backbone networks. Forced call terminations due to handoff call blocking are generally more objectionable than new call blocking. In general, most of the previously proposed schemes for radio channel allocation in cellular networks reduce handoff call blocking probability substantially at the expense of increasing the new call blocking probability by giving higher priority to handoff calls over new calls in admission control. This reduces the total admitted traffic and results in inefficient utilization of wireless channels. The trade off between new call blocking probability and handoff blocking probability should be defined on importance basis. We propose a performance metric equation that makes a trade off between the two probabilities depending on the network preferences. Using this equation we study the performance of various proposed channel reservation schemes. Also, a new dynamically adaptive channel reservation scheme (DACRS) is developed and compared with the various channel reservation schemes. The DACRS assigns handoff-reserved channels to new calls depending on the locality principle of the GSM in which the base station can know the position of the mobile terminal. Eventually, the DACRS is designed to improve channel utilization while satisfying the QoS of all calls. As is shown by the simulation results, the new DACRS outperforms current reservation schemes and results in more statistical gain, and powerful decisions for handoff reservation.