Efficient Algorithms for Cognitive Radio Networks

认知无线电(CR)是一种在动态和不可预测的条件下实现最佳性能所必需的具有智能感知和学习层的无线电。CR可以通过其感知来动态地调整其行为，以适应无线电环境和频谱策略。认知无线电技术最关键的组成部分之一是频谱感知(SS)。通过感知和适应环境，认知无线电能够填补频谱空洞，服务于次用户，而不会对主用户造成有害干扰。SS技术可以分为两类：本地SS和协作SS(CSS)。局部检测技术主要有三种：匹配滤波检测技术、能量检测技术和环素检测技术。Css显著缓解了由于破坏性无线电条件而导致的传感性能恶化。软件无线电(SDR)是实现CRS的关键使能技术。*该提案考虑了CR网络(CRN)的改进算法。该提案将研究有效的盲SS/CS技术，这些技术将在提高检测概率的同时减少感知时间；将考虑开销折衷。该提案还将研究用于CRN的基于簇的扩频(CBSS)方法，该方法将在噪声不确定性、低信噪比(SNR)和多径衰落条件下保持高性能。将对存在多个主要用户的情况进行调查和分析。研究如何利用自适应的联合感知门限和感知时间来提高本地SS的性能，以及利用联盟博弈理论来提高CRN中宽带CS的能量效率。*车载自组织网络(VANET)由于对车辆之间以及与基础设施进行通信以确保道路安全和引入新服务的需求不断增加而呈上升趋势。该提案考虑了CR-VANET的有效解决方案，这些解决方案将考虑感知频谱，在移动时形成集群。将研究快衰落下的扩频技术，以服务于CR-VANET。在CR-VANET中保护主用户(PU)的方法需要研究和开发。将研究有效的媒体访问控制(MAC)方案，以提高CR VANET的感知性能。调查移动参数变化的影响(高速、多变的拓扑等)将对传感性能和精度进行研究。*这项建议旨在为研究生和本科生提供一个研究环境，让他们参与计算机通信网络中最先进的主题，这肯定会增强他们的潜力和知识。

Cognitive radio (CR) is a radio with an intelligent layer of awareness and learning necessary to achieve optimal performance under dynamic and unpredictable conditions. CR can dynamically adapt its behavior, through its awareness, to the radio environment and spectrum policy. One of the most critical components of CR technology is spectrum sensing (SS). By sensing and adapting to the environment, a CR is able to fill in spectrum holes and serve secondary users without harmful interference to the primary users. SS techniques can be categorized into two categories: local SS, and collaborative SS (CSS). There are three main local techniques which are: matched filter detection technique, energy detection technique, and cyclostatinary detection. CSS significantly alleviates the deterioration of sensing performance due to destructive radio conditions. Software-defined radio (SDR) is a key enabling technology to realize CRs. ******The proposal considers improved algorithms for CR Networks (CRNs). The proposal will investigate efficient blind SS/CSS techniques that would lead to decrease sensing time while improving the probability of detection; overhead compromise will be considered. The proposal will also investigate cluster-based SS (CBSS) approaches for CRNs that would maintain high performance under noise uncertainty, low signal-to-noise-ratio (SNR) conditions, and multipath fading conditions. Scenarios, where more than one primary user exists, will be investigated and analyzed. Performance enhancement of local SS using adaptive joint sensing threshold and sensing time will be investigated as well as enhancing energy efficiency for wideband CSS in CRNs using coalitional game theory.******Vehicular ad hoc network (VANET) is on the rise due to increasing demands for vehicles to communicate with each other and with the infrastructure to ensure road safety and to introduce new services. The proposal considers efficient solutions for CR-VANETs that would consider sensing the spectrum, forming clusters while on the move. SS techniques under fast fading will be investigated to serve CR-VANET. Methods to protect the primary user (PU) in CR-VANET need to be investigated and developed. Efficient medium access control (MAC) schemes that would lead to enhance the sensing performance in CR VANET will be investigated. Investigating the impact of changing mobility parameters (high speed, changeable topology, etc.) on sensing performance and accuracy will be investigated. ***This proposal aims to provide a research environment where graduate and undergraduate students get involved in state-of-the-art topics in computer-communication networks that definitely will enhance their potential and knowledge.