Spectrum Sensing Methods and RF Architectures for Cognitive Radios

Abstract

In this paper, we review some of the recent patents on spectrum sensing techniques for cognitive radio (CR) applications. The presented patents are categorized under: 1) spectrum sensing algorithms and architectures, 2) spectrum sensing and data communication and 3) cooperative spectrum sensing. The presented patents include special sensing algorithms that are based on the multi-resolution spectrum sensing (MRSS) approach, which ensures reliability of the spectrum sensing in wireless RF environments. We also discuss a CR patent that includes multiple RF chains to perform simultaneous cognitive tasks. Several patents that consider cooperative sensing are also presented as a solution to the hidden terminal problem inherent in wireless networks. We review the advantages and disadvantages of the presented patents and propose future directions for developing spectrum sensing techniques for CR’s. Keywords: Cognitive radio, cooperative spectrum sensing, dynamic spectrum access, energy detection, multi-resolution spectrum sensing, opportunistic spectrum access, spectrum sensing