Development of a measurement system for spectrum awareness

Dynamic spectrum access (DSA) is an attractive approach to solve the spectrum scarcity problem. Among DSA techniques, spectrum overlay is an approach where the spectrum licensed to a primary user (PU) is shared by a secondary user (SU) while protecting the PU from the interference caused by SU spectrum reuse. In the case where PU traffic is dynamic, spectrum sharing is difficult as satisfying requirements of spectrum sensing, the challenging accuracy, quickness and low cost requirements in practice, is difficult. For this issue, we propose a new concept of smart spectrum access (SSA) where useful information related to PU spectrum utilization is used to achieve not only the above requirements but also more efficient spectrum utilization. We also show an approach to realize practical SSA and it consists of a spectrum awareness system (SAS) and a dynamic spectrum access system (DSAS). The main role of the SAS is to provide useful information to the DSAS. The information can be obtained by the SAS through spectrum utilization measurement and analysis of the measurement data. In this paper, we present a framework for smart spectrum access and discuss the challenges of this approach. In addition, we report some of the experimental results related to SAS.