On the Grade-of-Services in the Sharing of Radio Spectrum

Recent research have shown that spectrum can be utilized more efficiently through secondary usage of frequency bands which has been occupied by an existing system. In the future, the secondary radio operator may also want to provide Grade-of-Service (GoS) guarantee to its users. Our model assumes a primary and a secondary system, with both having GoS requirement, and another secondary system with best-effort admission. We develop two possible spectrum ownership models which are aligned with the proposed scenarios identified by the FCC. The first ownership considers the case when a spectrum licensee leases out resources to multiple service providers, with two of them having GoS requirements. In this model, the licensee is free to proportion resources among the systems to maximize revenue. The second ownership model considers the case when a spectrum licensee who also owns the primary network, wishes to share its spectrum with the two secondary systems, with one of them having GoS requirement and the other providing only best-effort admission. We further consider the revenue function of both scenarios based on two shared access schemes. In the first scheme, we introduce a probability to regulate the admission of users to the secondary system. In the second scheme, the primary system reserves n of its frequency slots for it own use. From the analytical results, the introduction of the extra design parameter in each scheme provides the flexibility to improve the achievable revenue as compared to a strict first-come-first-serve (FCFS) approach.