Prioritization Schemes in Queuing Handoff and New Calls to Reduce Call Drops in Cellular Systems

This paper proposes different queuing scenarios to avoid dropping of handoff and new calls in a cellular phone network, which is essential when the network has certain restrictions on the available frequencies. This limitation degrades the performance of the system and more sites are required to achieve the desired capacity and coverage. However, this leads to a higher percentage of call drops during handoff. This paper presents a queuing technique for both new and handoff calls to reduce the probability of call drop in such a system, leading to improvement in QoS. The proposed scenarios show better system performance. The blocking probability is reduced from 2% down to 0.04% for queuing handoff calls and from 2% to 1.14% when queuing new calls using the same technique. The four different presented approaches are: 1) only new calls are queued; 2) only handoff calls are queued; 3) by using all available channels; 4) by using only half. The queuing size also plays an important role for both new and handoff calls.