机会式频谱接入的理论与应用研究

发布时间：2019-06-29 18:17

【摘要】：机会式频谱接入作为一种可以提高频谱利用率的新技术,近年来得到了学术界和工业界的广泛关注。在机会式频谱接入策略中,当授权频谱空闲时,认知用户机会式接入到空闲频谱进行通信。当授权用户返回时,认知用户需要立即退出授权信道,以避免对授权用户的干扰。本文主要研究了机会式频谱接入中的频谱感知调度问题、机会式频谱接入在蜂窝网络和毫微微蜂窝网络中的应用。论文的主要内容包括：研究了基于机会式频谱接入的无线网络中,当存在多个不同业务类型的授权用户,并且认知用户经历时变信道时的频谱感知调度问题。我们提出了一种新的基于信息预测的频谱感知调度策略。在该策略中,我们通过马尔科夫链来预测认知用户的信道状态信息,并利用授权用户的业务特征信息预测授权信道在下一帧空闲的概率。通过这些预测信息,认知基站调度认知用户在不同的授权信道上进行感知和传输,以最大化认知无线电网络效用。在该频谱感知调度策略中,我们同时考虑网络吞吐量和公平性这两个重要网络指标,并把该调度策略描述成一个优化问题。随后,我们通过匈牙利算法求出该优化问题的最优解。所提出的基于信息预测的频谱感知调度策略可以很好的权衡网络吞吐量和公平性这两个指标,在保证认知用户之间的公平性的同时,获得较高的网络吞吐量。在基于机会式频谱接入的蜂窝网络中,研究了如何对接入过程进行建模,和分析网络的业务服务等级(GoS)性能。首先,我们给出了基于机会式频谱接入的蜂窝网络的网络架构。蓦于非跳转和跳转模式,我们提出了两种适用于蜂窝网络的机会式频谱接入策略。然后,我们通过构建三维连续马尔科夫链,对蜂窝网中的机会式频谱接入策略进行建模,以分析基于机会式频谱接入的蜂窝网的GoS性能。通过获取的GoS性能参数,我们分析了基于机会式频谱接入的蜂窝网的频谱利用率和给定目标GoS性能指标的情况下,基于机会式频谱接入的蜂窝网能够承载的业务强度范围。在基于机会式频谱接入的毫微微蜂窝网络中,研究了混合式接入模式中的激励机制。我们提出了一种动态频谱分配的方法,以激励无线运营商和毫微微蜂窝采用混合式接入模式。在该方法中,为了激励毫微微蜂窝分享有限的资源来服务宏用户,宏基站将会分配一部分本该分配给室内宏用户的频谱资源给毫微微蜂窝基站。从而毫微微蜂窝基站能够得到更多的频谱资源来提高毫微微蜂窝用户的通信质量。我们设计了一个协议来完成我们所提出的动态频谱分配方法,并且将毫微微蜂窝基站中的资源分配问题描述成一个优化问题,利用对偶分解的方法来求得最优解。通过采用我们所提出的动态频谱分配的方法,运营商和毫微微蜂窝用户都可以从中受益。一方面,宏基站能够在保证宏用户的通信质量的前提下,节约一部分频谱资源。另外一方面,毫微微蜂窝基站能够得到更多的频谱资源,以提高毫微微蜂窝用户的通信质量。
[Abstract]:Opportunistic spectrum access, as a new technology that can improve the spectrum utilization rate, has received extensive attention from the academic community and the industry in recent years. In an opportunistic spectrum access policy, that cognitive us opportunistic access to the idle spectrum when the authorized spectrum is idle. When the authorized user returns, the cognitive user needs to exit the authorization channel immediately to avoid interference to the authorized user. In this paper, the spectrum-aware scheduling problem in opportunistic spectrum access is studied, and the opportunistic spectrum access in the cellular network and the femtocell network should be discussed. Use. The main content package of the paper in the wireless network based on opportunistic spectrum access, when a plurality of authorized users of different service types are present and the cognitive user experiences the time-varying channel, Degree problem. We present a new information-based, information-based, spectrum-aware tone. in the strategy, we use the Markov chain to predict the channel state information of the cognitive user, and use the service characteristic information of the authorized user to predict that the authorized channel is idle in the next frame the cognitive base station schedules the cognitive users to perceive and transmit on different authorized channels in order to maximize the cognitive radio network through the prediction information, in that spectrum-aware scheduling strategy, we also consider the two important network indexes of network throughput and fairness, and describe the scheduling strategy as an excellent The question of the optimization is then determined by the Hungarian algorithm. The proposed spectrum-aware scheduling strategy based on the information prediction can balance the two indexes of network throughput and fairness, while ensuring the fairness among the cognitive users, and obtaining a higher network. throughput. In a cellular network based on opportunistic spectrum access, we study how to model the access process and to analyze the service level of the network (G S) Performance. First, we give a cellular network based on opportunistic spectrum access network architecture. For non-jump and jump modes, we propose two opportunistic frequencies for cellular networks the spectrum access strategy is then used to model the opportunistic spectrum access policy in the cellular network by building a three-dimensional continuous markov chain to analyze the cellular network based on the opportunistic spectrum access, GS performance. Based on the obtained GS performance parameters, we analyzed the spectrum utilization rate of the cellular network based on the opportunistic spectrum access and the given target GS performance index, and the cellular network based on the opportunistic spectrum access can carry the industry. In a femtocell network based on opportunistic spectrum access, a hybrid access mode is studied The incentive mechanism in the formula. We propose a dynamic spectrum allocation method to excite the wireless carrier and the femtocell. In the method, in order to excite the femtocell to share a limited resource to serve the macro user, the macro base station will allocate a portion of the spectrum resources that should have been allocated to the indoor macro user, The femtocell base station can obtain more spectrum resources to improve the femtocell base station. We have designed a protocol to complete the dynamic spectrum allocation method proposed by us, and describe the resource allocation problem in the femtocell base station as an optimization problem. A method, an operator and a femtocell user to obtain an optimal solution by using the dynamic spectrum allocation proposed by us on the one hand, the macro base station can save the communication quality of the macro user, in a further aspect, that femtocell base station is able to obtain more spectral resources to improve the femtocell
【学位授予单位】：华中科技大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TN925

【共引文献】