Real-Time Spectrum Access in Heterogeneous Wireless Networks Competition, Deployment and Pricing

The first decade of twenty-first century has witnessed the spread of innovative wireless technologies: novel wireless network architectures and services, operations in unlicensed bands, advanced mobile devices and smartphones. All these have pondered growing demand for wireless broadband services, so that more spectra are required. Consequently, the advent of flat-rate service pricing for mobile broadband services plus continuous investments in a network infrastructure and shortage of licensed spectrum make it more difficult for current wireless operators (OPs) to financially sustain themselves in a competitive environment. Since existing, fixed spectrum allocation (FSA), mechanism offers very limited flexibility, dynamic spectrum access from the market point of view is exploited here to support such flexibility. A framework of competitive spectrum access, where available spectrum can be leased based on the outcome of competition between heterogeneous wireless operators in a short-term fashion, is reviewed in this thesis. The main objectives are: (1) to maximize spectrum efficiency by utilizing market mechanisms in a heterogeneous setting, and (2) to identify which conditions and criteria should be applied to allow heterogeneous wireless networks to be viable in the marketplace. Under the competitive spectrum access framework, we explore three directions to tackle these objectives for a case of a two-operators system. First, we will look at how an inter-operator competition can affect the operator profits under an asymmetry in their networks. Then, we will analyze which deployment strategies in a heterogeneous environment should be utilized. Finally, we will consider which pricing strategies can be applied by competing OPs to sustain themselves. Through analysis and extensive simulations, we show that heterogeneous access architectures and the scalable infrastructure deployment could improve not only spectrum utilization efficiency, but also facilitate viability of spectrum allocation in a competitive environment. As a conclusion, we believe that techno-economical approach used to assess a feasibility of the framework could help in the designing of future wireless systems to efficiently utilize both the infrastructure and the spectrum resource.