Collaborative Research: Overcoming Technological Challenges for Spectrum Trading

无线网络在不同时刻、不同地理位置的动态和不均匀的业务负载，导致一些频段的利用率严重不足，而另一些频段则严重拥挤。该项目研究了宽带频谱交易中出现的一些基本和具有挑战性的技术问题，以实现频谱使用的卓越技术、经济和社会价值。该项目是一项跨数学和无线网络技术的跨学科研究。在无线技术方面，本研究项目成果可以显著提高频谱效率和用户体验，同时有利于公共安全、远程医疗和社会服务等许多现实需求。在数学方面，研究工作将导致更有趣的问题的公式与现实世界的应用，并发现解决这些问题的新工具。作为解决宽带频谱交易带来的技术挑战的综合研究，项目任务集中在三个相互关联的重点研究方向：1)新图论问题；2)基于新图的资源分配和效用优化；3)物理层技术和效用设计。具体而言，该项目考虑了图的明智划分问题和加权图中最优不相交路径的新问题，并使用最小边权路径效用。针对这些问题开发的新解决方案和工具可以应用和推广，以解决宽带频谱交易中的各种资源分配和效用优化问题。此外，该项目还解决了频谱交易产生的新的基本物理层问题。这些实现问题包括宽带信道估计、动态导频放置、干扰限制导频功率控制和低复杂度宽带频谱传感。为了建立效用函数曲线，并为更有效的宽带频谱交易开发精细粒度参数效应建模方法，该项目采用基于群体理论的方法来设计和执行详细的测试和分析，以微调包含用户体验和满意度的有效效用函数。研究结果也有望产生强大的社会影响，并为政府监管政策制定和无线通信宽带频谱交易的技术发展提供更好的技术见解和有效的指导方针。

The dynamic and uneven wireless network traffic load at different time instants and geographical locations has led to substantial underutilization of some spectrum bands while severely crowding others. This project investigates a number of fundamental and challenging technical issues that arise from broadband spectrum trading for achieving superior technical, economic, and social values of spectrum use. The project is an interdisciplinary research effort across mathematics and wireless network technologies. With respect to wireless technologies, this research project outcomes can significantly improve spectrum efficiency and user experience, while benefiting many real-life needs, such as public safety, telemedicine, and social services. On mathematics, the research effort will lead to the formulation of more interesting problems with real world applications and the discovery of new tools for solving such problems. As a comprehensive investigation to overcome technical challenges that arise from broadband spectrum trading, the project tasks focus on three inter-related key research directions: 1) new graph theory problems, 2) new graph-based resource allocation and utility optimization, and 3) physical layer techniques and utility design. Specifically, the project considers new problems on judicious partitions of graphs and new problems on optimal disjoint paths in weighted graphs using minimum-edge-weight path utility. New solutions and tools developed for such problems can then be applied and generalized for solving various resource allocation and utility optimization problems in broadband spectrum trading. Furthermore, the project addresses new fundamental physical layer issues that arise from spectrum trading. These implementation issues include broadband channel estimation, dynamic pilot placement, interference limited pilot power control, and low complexity broadband spectrum sensing. To establish utility functional curves and to develop means for modeling parametric effects in fine-granularity for more effective broadband spectrum trading, the project applies group-theory-based methodologies to design and carry out detailed tests and analysis in order to fine-tune effective utility functions that incorporate user experience and satisfaction. The research results are also expected to lead to strong social impacts and to provide better technical insights and effective guidelines on governmental regulatory policymaking and technological development regarding broadband spectrum trading for wireless communications.