On Reducing Multiband Spectrum Sensing Duration for Cognitive Radio Networks

In this work, the total spectrum sensing duration required for cognitive radios in multiband environments is studied to minimize the reactive handoff latency. Two spectrum sensing strategies, namely window-based and sample-based sensing, are evaluated to estimate channel workload and idle time probability. Channel workload is the percentage of time the band is used by other wireless networks. Idle time probability is defined as the probability of usable durations for the cognitive radio communications. The mean square error performance of the estimations is provided for both sensing strategies in the case of energy detection based sensing and realistic interarrival time distribution of packets. It is shown that, sample-based strategy requires half of the total multiband spectrum sensing duration compared to its window-based counterpart, if the hardware switching delay is under a specific threshold.