Multiband Sensing for Area Recovery

Cognitive radios are being proposed for recovering unused spectrum holes in time and space. Unfortunately the metric of detection-sensitivity while being useful for algorithm designers is not indicative of a system’s ability to recover spectrum holes (especially spectrum holes in space). In this paper we extend the safety and performance metrics of Fear of Harmful Interference (FHI ) and Probability of Finding a Hole (PFH ) from single primary on a single tower to multiple primaries on multiple towers. We show how a simple multiband algorithm which dynamically computes the detection threshold based on sensed power in multiple bands can recover significantly more area than a singleband detector which makes decisions based on in-band information. Effectively Multiband detection acts as a proxy for increasing the number of users.