To counter the inefficiencies of the current spectrum usage, regulatory bodies, all over the world, are exploring ways to deregulate the spectrum market by allowing flexible dynamic spectrum access (DSA) in a broad range of spatio-temporal scale. Recent advances in radio technology have given an impetus to this trend. For DSA to fulfill its promise of economic and societal impact, wireless services based on DSA must be commercially successful, and a tangible spectrum market must evolve that can be supported by technology. This research project will build a realistic DSA architecture for cellular networks supported by appropriate market mechanisms in an integrated fashion that is both technically and economically viable and efficient. This is a truly trans-disciplinary approach spanning the fields of wireless networking and systems, algorithmics, economics, simulation and modeling, which leads to a deeper understanding of the dynamics of the spectrum market by (i) realistic modeling of various market entities (i.e., buyers, sellers, and the market mechanisms), (ii) dynamic spectrum demands and bids based on innovative and realistic population dynamics models, and (iii) new and robust market clearing mechanisms with provable performance guarantees. The results will be validated using large-scale simulations, and experiments on a prototype test bed with reconfigurable radio hardware. In addition to fostering new topics in trans-disciplinary education, this project will offer insights into market driven spectrum sharing, provide useful tools for policymakers, and ultimately guide spectrum policy decisions in DSA technology. This will, in turn, open up new business opportunities in the use of wireless spectrum.
To counter the inefficiencies of the current wireless spectrum usage, regulatory bodies all over the world are exploring ways to deregulate the spectrum market by allowing flexible dynamic spectrum access. The idea is how to share blocks of spectrum dynamically by competing entities to maximize effectiveness and to drive economic progress. Recent advances in radio technology have given an impetus to this trend. For dynamic spectrum access to fulfill its promise of economic and societal impact, wireless services based on this technique must be commercially successful, and a tangible spectrum market must evolve that can be supported by technology. This research project investigated several issues both in terms of 1) radio access and spectrum sharing technologies, and 2) market mechanisms. In the technology part, we developed a broad understanding of spectrum sharing issues and multi-channel radio access mechanisms. More specifically we developed several models, protocols and access mechanisms where multiple competing entities access a shared spectrum band efficiently for various technologies. We also investigated the related issue of wireless interference in the same or across channels that often hinders effective sharing. We developed effective models to measure and characterize these aspects. In another thread, we saught to understand the nature of actual spectrum demand by mobile cellular subscribers. This effort developed a broad understanding of spatio-temporal access patterns in real world supported by strong analytics on actual cellular network data. To understand market mechanisms, we investigated relevant pricing and auction mechanisms. The pricing investigation is related to dynamically pricing traffic by the service provider so that users are incentivized to shift load to non-peak periods. The developed auction mechansims are related to efficient auction design such that auctions are "truthful" and also they optimize a given social choice function (e.g., revenue or social welfare). As per broader impact, the project generated 20+ publications. It also supported research training of a number of PhD students, six of whom already graduated and are now employed in R&D positions in industry or in academia. The PIs and students gave a number of public talks. The project also helped mature the existing collaboration with an industry lab (Alcatel-Lucent Bell Labs) and the interactions were mutually beneficial to Bell Labs as well as the graduate students in the university. The project also supported three REU students, two of whom later joined graduate programs.
