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The current spectrum allocation model aims to avoid interferences in licensed spectrum communications without further concerns regarding spectrum usage. Because the radio spectrum is a finite resource, several approaches have been presented in order to improve the effectiveness of its utilization. The main contribution of this work is to present an opportunistic approach to spectrum sensing and allocation. Compared to other alternatives, our approach presents significant improvements in the spectrum access and utilization, improving network throughput up to 16 times.

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Studies in Dynamic Spectrum Access often consider aspects of primary communication in their schemes. However, the primary spectrum access modelling is generally over simplistic. This paper considers a realistic modelling of the primary traffic and list a series of parameters that should be considered during spectrum reuse. By modelling primary and secondary communications, a better understanding of secondary spectrum access can be achieved. Furthermore, by studying both primary and secondary communication parameters and their relation, it is possible to tune secondary networks in order to optimize spectrum reuse. The results obtained demonstrate how appropriate parametrization can lead to significant improvements in network performance. Simulation results show that it is possible to attain up to 90% of success during data transfers for secondary when the overall spectrum use of the primary users is at 50%.

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