A distributed framework with a novel pricing model for dynamic spectrum access to secondary users in infrastructure based wireless networks

Abstract

Ever increasing demand for radio spectrum and its current underutilization have made the radio spectrum a scarce and expensive resource. In this thesis, a system for allowing unsubscribed Secondary User (SU) access to the underutilized spectrum in the licensed bands in infrastructure based networks is proposed, with minimum modifications to the current Wireless Service Provider (WSP) infrastructure. The proposed distributed system framework enables the orthogonal co-existence of subscribed Primary Users (PUs) and SUs at the same Base Station (BS). The rationale of this thesis is the paradoxical fact that, the WSPs invest heavily in licensing the spectrum, and this licensed spectrum goes underutilized due to the variable usage in time and location of the subscribed PUs. Allowing temporary access to SUs at the BSs of the WSPs, whenever the spectrum is underutilized, presents an opportunity for the WSPs to generate additional profits from SU access. The aim of this thesis is to present a system framework for enabling SU access at the BSs considering both the technological and the economic perspectives. The signaling framework for SU access, SU identification, PU-SU joint resource management model, autonomous BS selection and a price-based handoff at the SU terminal are the key technological contributions in this thesis. The dynamic incentive based pricing model for charging SUs, along with equilibrium analysis with differentiation of SU wireless service for realizing competitive SU pricing among multiple WSPs are the key economic contributions. The proposed framework and pricing model is aimed at achieving the dual goal of temporary wireless access for unsubscribed SUs, as well as generating additional profits to the WSPs. This proposed framework is thus an intermediate step between the current infrastructure based networks and the cognitive networks of the future.