Energy-sensitive cooperative spectrum sharing: A contract design approach

In cooperative spectrum sharing, secondary users consume their energy to relay primary user's traffics in exchange for permission to access the spectrum licensed to primary user. As energy consumption is an important issue for mobile secondary users operating on batteries, it is reasonable for these secondary users to be energy-sensitive. In this paper, we utilize contract theory to deal with the cooperative spectrum sharing problem under the condition of secondary users being energy-sensitive. In our scheme, primary user wishes to benefit from cooperative communication with secondary users and selling spectrum access opportunities on the premise of not degrading its own performance. Primary user's objective is to design an optimal contract that maximizes its utility and offer it to secondary users. Secondary users are classified into different types according to their characteristics. We analyze the optimal contract design problem under symmetric and asymmetric information scenarios and propose a low complexity algorithm called TSSOA to find the optimal contract for primary user. Finally, we present and analyze the numerical results, which confirm the efficiency of the proposed scheme.