Lessons learned from an extensive spectrum occupancy measurement campaign and a stochastic duty cycle model

Several measurement campaigns have shown that numerous spectrum bands are vacant although licenses have been issued by the regulatory agencies. Dynamic spectrum access (DSA) has been proposed in order to alleviate this problem and increase the spectral utilization. In this paper we present our spectrum measurement setup and discuss lessons learned during our measurement activities. We compare measurement results gathered at three locations and show differences in the background noise processes. Additionally, we introduce a new model for the duty cycle distribution that has multiple applications in the DSA research. Finally, we show that the primary user signal bandwidth has major impact on the correlation properties of the duty cycle in the frequency domain.