Opportunistic Channel Access Scheme for Cognitive Radio System Based on Residual White Space Distribution
The authors propose an opportunistic channel access scheme for cognitive radio-enabled secondary networks. In their paper, they model the channel occupancy due to Primary User (PU) activity as a 2-state Alternating Renewal Process, with alternating busy and idle periods. Once a Secondary Node (SN) senses the channel idle, the proposed scheme uses the residual idle time distribution to estimate the transmission duration in the remaining idle time, subject to an acceptable PU interference constraint. The SN transmits the frames within the transmission duration without further sensing the channel, thereby reducing the average sensing overhead per transmitted frame.