SE PhD Prospectus Defense of Emir Kavurmacioglu

TITLE: Oligopolies in Private Spectrum Commons: Analysis and Regulatory Implications ABSTRACT: With the advent of wireless communications, radio spectrum is becoming an ever more valuable commodity. The conventional methods of static partitioning of the radio spectrum are falling short of the increasing needs for spectrum access. In addition to the current efforts of clearing government controlled spectrum or utilizing TV White Spaces, which can only make a limited amount of spectrum available in the near future, it is predicted that dynamic spectrum allocation or spectrum sharing on an opportunistic temporal and spatial basis will be a sustainable long term method to address this growing need. In an effort to provide the initial momentum in this direction, recent initiatives by the FCC propose to allow mobile providers to offer spot service of their licensed spectrum, hence paving the way to dynamic secondary spectrum markets. In this proposal we consider an oligopoly model where network providers compete in a dynamic secondary spectrum market. In our preliminary results, we characterize outcomes of a market where multiple providers are drawn into competition for secondary demand and secondary users opportunistically choose the available spectrum based on the price at which it is offered. We first analyze the market outcomes when providers implement a coordinated access policy and show through a stochastic and game theoretic model that the competition always leads to a price war outcome. Through our analysis, we identify profitability conditions and fundamental price thresholds, including break-even and market sharing prices. We next consider a competition when providers opt for an uncoordinated access policy and analyze it under two traffic models: stochastic demand and its fluid approximation. In contrast to the results of the coordinated access policy, we observe that market sharing becomes a viable market outcome. All of our results hold for general forms of demand, thus avoiding restricting assumptions of customer preferences and the valuation of the spectrum. We then present our future research plans, which include improving the customer choice modeling and the move to a social welfare analysis, by introducing quality of service as a metric and by considering more realistic user preferences towards services being offered. We also detail our plans to consider the oligopoly competition in a spatial setting in order to capture this dimension of the radio spectrum, alongside its temporal characteristics. COMMITTEE: Advisor: David Starobinski, SE/ECE; Michael Caramanis, SE/ME; Murat Alanyali, SE/ECE; Assaf Zeevi, Columbia Business School