Prediction based cognitive spectrum access

A prediction-based spectrum access for cognitive radio (CR) is considered. In a typical scenario, CR accesses the communication channels as a secondary user (SU), under the requirement for collisions avoidance with the primary users (PU). In order to meet this requirement, CR frequently senses the communication channels and estimates their availability. Generally, sensing and transmission processes are mutually exclusive, which turns the sensing time into an overhead. Therefore, CR has a strong incentive to predict the future availability of the channels. Consequently, by sensing less, CR is able to increase the proportion of time allocated for the transmissions. We propose a novel analytical model of CR which consists of communication processes and cognitive components. The communication processes include packet arrivals, queueing and transmissions, while the cognitive components include sensing, estimation, multi-step ahead prediction of the channels´ states and a component of decision-making. The prediction based policies show a significant improvement in the performance measures of throughput and delay compared to the reactive behavior.