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Spectrum Database Construction based on HMM and Spectrum Sharing in Multiple Primary Users Environment

In recent years, many researchers focus on a measurement-based spectrum database (SD) that utilizes the actual received power obtained by spectrum sensing as an enabler for an efficient spectrum sharing. In this paper, in an environment where multiple transmitters are switched ON/OFF, we propose a spectrum sharing method and verify the influence of error at SD construction. SD is constructed by placing multiple sensors in the radio environment for performing spectrum sensing and statistically processing the result of learning by Hidden Markov Model (HMM). In the proposed method, it is possible to reuse temporal and spatial white space with high efficiency by using spectrum sharing in cooperation with SD. The simulation results confirm the effectiveness of the proposed method.