Database-aided sensing for radar bands

Radar bands have been suggested as one of the most promising candidates for spectrum sharing, as they occupy a considerable amount of spectrum, despite their usage efficiency being generally low. Although geo-location database and dynamic frequency selection were chosen by regulators as the preferred methods for enabling the coexistence between radar systems and low-power devices, their static nature and lack of flexibility may not enable an efficient utilization of this spectrum. In order to overcome this issue, we propose in this article a hybrid spectrum access technique, called database-aided sensing. We describe and test the ability of this technique to discern both spatial and temporal spectrum opportunities that arise from circularly and sector scanning radars. The obtained results were encouraging, taking into account the sensing sensitivity levels required to protect radar systems, even when the database awareness about the radio environment is limited.