Dynamic Spectrum Access Networks With Heterogeneous Users: How to Price the Spectrum?

In a pricing-based spectrum trading market, an interesting issue is to study how secondary users make their selections in a rational manner when there are available spectrum of different qualities in the market. In this case, primary systems inherently require a precise pricing strategy to maximize their profits especially when the secondary users' selection preferences are not uniform nor predictable during the dynamic access. In this paper, we propose a novel spectrum pricing mechanism for primary systems by taking into account the selection preferences of heterogeneous secondary users and quality diversity of leased spectrum caused by different interference levels and channel fading characteristics. Our work mainly focuses on exploring the optimal pricing solution in the case that the selection preference of secondary buyers is stochastic. In the proposed system model, the spectrum to be leased is divided into a series of uniform subchannels of various qualities for spectrum trading. We analyze the impact of secondary users' preference on spectrum trading and propose an iterative algorithm for spectrum pricing by introducing the Hotelling model to describe the relationship between the spectrum diversity and the primary system's utility. Proofs of the integrability of the utility function and existence of Nash equilibrium used in the proposed algorithm are provided. Numerical results demonstrate the effectiveness of the proposed pricing method in improving the primary system's profits.