Channel reservation in cognitive radio networks with the RESTART retransmission strategy

In this paper, channel reservation to prioritize ongoing secondary users´ (SUs) calls over new SUs´ requests in cognitive radio networks (CRNs) with delay tolerant traffic and the RESTART (also known as preemptive repeat identical) retransmission strategy is analyzed and evaluated. Additionally, an analytical approach to approximately evaluate the performance of CRNs under the RESTART retransmission strategy is proposed and developed. It is shown that channel reservation is an effective mechanism both to reduce the negative impact of retransmissions and to widen the conditions under which system stability can be achieved. To the best of the authors´ knowledge, mechanisms to modify the failure process in CRNs have been neither analyzed nor evaluated in the literature.