A preemptive priority queuing scheme for handovers in TETRA networks

As a key element in wireless cellular networks, handover procedure has a significant impact on the system's performance. In this paper, we present a preemptive priority queuing method to provide better Quality of Service (QoS) by decreasing handover failure probability in Terrestrial Trunked Radio (TETRA) networks. As a specialty of TETRA systems, the priority criteria should be satisfied when bringing in a new method and it makes the algorithm more complex. Considering different levels of users' priority and call status, the proposed algorithm uses a computable hybrid priority to evaluate different calls. The major characters of this method, which simulated in a typical scenario of TETRA networks, are compared with some other algorithms. The result shows that this new scheme can reduce probability of handover failure effectively and provide stable service quality for higher priority users even in extremely high cell load condition.