Stable Matching for Spectrum Market with Guaranteed Minimum Requirement

To enable dynamic spectrum access, service providers with spare spectrum (sellers) trade with those who are in need of additional spectrum (buyers). In a spectrum market, the transaction result is essentially a match between sellers and buyers. Though it is tempting to optimize the matching over certain utility functions, a stable matching is more desirable, since it takes into account a diverse set of preferences of buyers and sellers, and produces a matching result which no participants have incentives to deviate from. While existing works on spectrum matching only consider the maximum number of channels a buyer can purchase, in real-world scenarios, the minimum spectrum requirement should be satisfied to support the proper operation of wireless communication. To address this issue, in this paper, we present a new framework of spectrum matching with both maximum and minimum requirements. Different from conventional matching problems, the spectrum market poses distinctive challenges due to spectrum reusability. Instead of being sold exclusively to just one buyer, the same channel can be reused by multiple buyers who are not interfering with each other. To tackle this problem, we design a novel algorithm, called Extended Deferred Acceptance (EDA), that converges to an interference-free matching and guarantees the minimum spectrum requirement. We theoretically prove the stability of the matching result. Our simulation results show that EDA can achieve a 100% coverage on the minimum requirements, while alternative benchmark algorithms fail to do so, and buyers are more satisfied with the matching result of EDA than that of alternative algorithms.