A persistent link layer transmission strategy for efficient dynamic spectrum access

In this paper, we propose an efficient dynamic spectrum access protocol for secondary users (SU) communication over an agile single primary user (PU) channel. The proposed access scheme is optimized with respect to different SU back-off times and SU packet length. Via Markov chain models and numerical analysis, we derive the optimal SU packet length for optimal SU performance at a given PU traffic load. We evaluate the protocol performance in terms of SU goodput and PU collision ratio. An outline of the proposed protocol operation is also given, where the protocol adapts to the changing PU traffic load for optimized spectrum access performance. Our performance studies demonstrate that the proposed protocol offers significantly high channel utilization while keeping the PU collisions below a predefined acceptable threshold.