NeTS: Small: Collaborative Research: Learning to help: Trading spectrum ownership for performance

与大多数现有的动态频谱访问（DSA）范式不同，DSA范式在主用户（pu）和辅助用户（su）之间强加了一种“敌人”关系，该项目研究了一种新的DSA范式，该范式鼓励pu和su通过交易频谱所有权来相互帮助，以提高整体性能。具体来说，本项目设计了两种不同的方案：(1)给予和接受（GAT）和(2)网络编码+次要用户中继（NC+SR）。前者不需要改变pu的无线电或协议栈，而后者假设pu和su能够执行网络编码。在GAT中，用户单元帮助传输pu的流量，作为回报，用户单元被允许以干扰pu的方式访问许可频谱。帮助构成了“给予”部分，而破坏性频谱访问构成了“接受”部分。在NC+SR中，su可以在PU之间中继PU流量。在转发PU报文时，SU中继节点可以通过网络编码将SU报文编码到PU报文上，这样SU报文就可以“搭便车”到PU报文上。GAT和NC+SR都有望提高pu和su的性能。本课题研究了这两种方案的协议设计和性能优化问题。预计该项目的结果将鼓励现有授权用户采用DSA，以进一步提高无线网络的容量。该项目维持了一个合作研究团队，并涉及研究生和本科生，特别是代表性不足的少数民族学生，在研究。

In contrast with most existing dynamic spectrum access (DSA) paradigms which impose a `foe' relationship between primary users (PUs) and secondary users (SUs), this project investigates a new DSA paradigm which encourages PUs and SUs to help each other by trading spectrum ownership for improved overall performance. Specifically, this project designs two different schemes: (1) Give-And-Take (GAT) and (2) Network Coding + Secondary User Relay (NC+SR). The former does not need to change the radio or the protocol stack of PUs, while the latter assumes that PUs and SUs are capable of performing network coding. In GAT, SUs help deliver the traffic of PUs and in return are allowed to access licensed spectrum in a manner disruptive to PUs. The help constitutes the `give' part, and the disruptive spectrum accesses constitute the `take' part. In NC+SR, SUs help relay PU traffic between PUs. When relaying PU packets, SU relay nodes may encode SU packets onto PU packets via network coding, so that SU packets get a `free ride' on PU packets. Both GAT and NC+SR promise the improved performance of PUs as well as SUs. The project studies the issues of protocol design and performance optimization of the two schemes. Results from this project are expected to encourage incumbent licensed users to embrace DSA to further improve the capacity of wireless network. The project sustains a collaborative research team, and involves both graduate and undergraduate students, particularly the underrepresented minority students,in research.