NeTS: Small: Collaborative Research: Unleashing Spectrum Effectively and Willingly: Optimization and Incentives

在研究频谱使用的过程中出现了一个有趣的事实。一方面，无线设备（如智能手机、笔记本电脑和平板电脑）和带宽消耗大的应用程序的激增导致了频谱稀缺的问题。另一方面，美国联邦通信委员会（FCC）最近的一份报告显示，授权用户对已分配频谱的利用严重不足。为了消除有效利用频谱的障碍，本项目旨在：1)设计有效的频谱分配算法，使尽可能多的辅助用户（su）与主用户（PU）共存，同时考虑到主用户和主用户产生的干扰；2)制定激励机制，吸引频谱持牌人分享或许可其未充分利用的频谱，以更好地利用。在设计频谱分配方案时，采用物理干扰模型，使干扰更贴近实际。探索频谱分配与功率控制的联合优化，进一步提高频谱利用率。这可以产生有效的近似算法，保证与最优算法相比的性能，以及有效的启发式算法。该项目的另一项主要任务是设计激励拍卖，以吸引频谱持牌人与未持牌用户分享其频谱，以换取拍卖收益。研究了三种不同的应用场景：1)频谱持有者愿意与无牌用户共存，前提是无牌用户造成的累积干扰不会中断其自身的传输；2)允许小型网络运营商组成集体购买力集团，以增加其赢得频谱的机会；3)考虑了多个频谱持牌人之间的竞争。这项研究可以帮助确保美国的无线网络跟上对频谱不断增长的需求，以便它们能够支持越来越依赖于它们的活动，包括公共安全和医疗保健。设计的基于团购的激励拍卖可以为小企业提供与大品牌公司竞争的机会，并赢得对其业务成功至关重要的所需频谱的访问权。这些小企业是这个国家创造就业和经济增长的引擎。该项目涉及代表性不足的少数民族学生，以及K-12学生，以激发他们对科学和工程的兴趣。

An intriguing fact emerges during the study of spectrum usage. On one hand, the proliferation of wireless devices, e.g. smartphones, laptops, and tablets, and bandwidth-hungry applications has resulted in the problem of spectrum scarcity. On the other hand, a recent report by FCC reveals that the licensed users are extremely underutilizing the allocated spectrum. To remove the barriers to efficient spectrum utilization, this project aims to 1) design effective spectrum allocation algorithms to allow as many secondary users (SUs) to coexist with the primary user (PU) as possible while taking into account the interference generated by both SUs and PU; and 2) develop incentive mechanisms for enticing spectrum licensees to share or license their under-utilized spectrum for better utilization. While designing spectrum allocation schemes, the physical interference model is adopted to characterize the interference closely to reality. Joint optimization of spectrum allocation and power control is explored to further improve the spectrum utilization. This can lead to efficient approximation algorithms with guaranteed performance comparing with the optimum, as well as effective heuristic algorithms. Another major task of this project is to design incentive auctions for enticing spectrum licensees to share their spectrum with unlicensed users in exchange for the proceeds from the auction. Three different application scenarios are investigated: 1) the spectrum holder is willing to coexist with the unlicensed users under the condition that the cumulative interference caused by them does not interrupt its own transmission; 2) small network operators are allowed to form groups for collective buying power to increase their chances of winning the spectrum; and 3) the competition among multiple spectrum licensees is considered. This research can help ensure wireless networks in the USA keep pace with the continuously increasing demand for spectrum, so that they can support activities that increasingly rely on them, including public safety and health-care. The designed group-buying based incentive auctions can provide opportunities for small businesses to compete against big brand companies and win the access to desired spectrum that is essential to the success of their business. These small businesses are the engines of job creation and economic growth for the country. This project involves under-represented and minority students, as well as K-12 students to inspire their interests in science and engineering.