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认知无线网络中一种基于蚁群优化的频谱分配算法 总被引:1,自引:0,他引:1
针对认知无线电中的频谱分配问题,该文提出一种基于蚁群优化的频谱分配方法。该方法在授权用户和认知用户共存的认知网络模型中,通过蚁群访问各个认知节点,并释放信息素,从而实现概率型的全局搜索的并行频谱分配算法。与传统的频谱分配方式比较,该算法能够进行增强型学习积累,快速收敛到最优路径,从而获得了最优的平均信道效益。文中对该算法进行了分析和说明,并通过仿真证明了算法的有效性和稳定性。 相似文献
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基于认知无线电系统中Underlay频谱共享模型,提出了一种双门限频谱分配算法.给定两个信噪比门限,当信噪比低于较小的门限时,系统选择认知用户做中继协助授权用户进行数据传输,以授权用户信道容量最大化为优化目标进行频谱分配;当信噪比大于较大的门限时,系统允许认知用户之间进行低功率数据传输,以认知用户接入数量最大化为优化目标进行频谱分配;当信噪比介于两门限之间时,由授权用户单独进行数据传输.理论分析和仿真表明,当授权用户信噪比低于较小门限时,所提方法能提高授权用户的信道容量;当授权用户信噪比大于较大门限时,所提方法可以提高认知用户的接入数量. 相似文献
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传统的认知无线电频谱分配算法往往忽略节点的传输功率对网络干扰的影响,且存在节点间交互成本高的问题.为此,通过量化传输功率等级,以最大化弹性用户收益为目标,构建联合频谱分配与功率控制非合作博弈模型,证明了该博弈为严格潜在博弈且收敛到纳什均衡点.进一步,将随机学习理论引入博弈模型,提出了基于随机学习的策略选择算法,并给出了该算法收敛到纯策略纳什均衡点的充分条件及严格证明.仿真结果表明,所提算法在少量信息交互前提下能获得较高的传输速率,并提升用户满意度. 相似文献
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频谱分配技术是认知无线电的关键技术之一,为适应认知无线电系统的时变特性,频谱分配算法必须有较快的收敛速度。在干扰温度模型下,提出一种基于Kuhn-Munkras算法的认知无线电频谱分配策略。该策略利用Kuhn-Munkras算法可以实现最佳匹配并且收敛速度快的特性,根据不同的用户在不同信道上所产生的效益的差异性,实现认知用户和信道的最佳匹配。仿真表明,基于Kuhn-Munkras算法的频谱分配在性能上优于传统的配对算法和greedy算法。 相似文献
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功率控制是感知无线电重配置的重要内容之一。结合功率控制的动态频谱分配策略可以有效提高频谱分配的性能。文章构建了一种潜博弈模型,通过在授权链路保护算法中加入功率控制机制,进一步降低对系统中授权用户和其它感知用户的干扰,提高通信链路的信干噪比,改善分配算法的性能。仿真结果表明算法达到了预期的效果,保证了感知无线电系统可靠通信。 相似文献
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提出一种适用于"未充分使用"频段的定价算法。该算法基于非合作博弈模型,引入未充分使用频谱的收益因子,各授权用户在保证现有通信质量前提下以最大化收益为目标,通过用户之间的定价竞争,实现了一种分布式的动态频谱分配。仿真结果表明,该算法在频谱需求较大的情况下能有效提高"未充分使用"频谱的效益,同时算法收敛速度较快,便于实际应用。 相似文献
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认知无线电中基于Stackelberg博弈的分布式功率分配算法 总被引:1,自引:0,他引:1
在underlay认知无线电场景中,为了让认知用户能随机地接入主用户正在使用的授权频段,且对主用户产生的干扰不高于主用户能够容忍的干扰温度门限,该文采用Stackelberg博弈机制进行认知用户的发射功率分配。将主用户作为模型中的leader,认知用户作为follower,认知用户使用主用户的授权频段时需以干扰功率为单位支付给主用户相应的费用,而主用户则可以通过调整价格,限制认知用户产生的总干扰功率不高于其所能容忍的干扰温度门限,以便获得最大收益。同时,不同认知用户间根据主用户制定的价格,进行非协作博弈。仿真结果表明,与集中式的最优功率分配算法相比,该文可通过简单的分布式功率分配算法获得与其相近的系统性能,且主用户与认知用户间只需进行少量的信息交互,这与需进行大量信息交互的集中式最优算法相比,具有较大的优势。 相似文献
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动态频谱分配技术是认知无线电的一项关键技术,本文针对以OFDM为传输技术的认知无线电系统,提出了固定速率认知用户和变速率认知用户并存情况下的动态频谱分配新算法。本文算法以最小化每比特发射功率为目标,运用最小最大准则与分步求解的方法,对系统目标函数予以简化,在最大公平意义上对认知小区的空闲频谱资源进行动态分配。仿真结果表明,该算法具有较好的公平性,在固定速率用户功率最小化需求和变速率用户吞吐量最大化的需求之间取得了比较好的平衡,适用于两种需求用户并存环境下的认知无线电系统。 相似文献
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认知无线电频谱分配的博弈论方法 总被引:2,自引:0,他引:2
认知无线电中频谱分配问题目前受到了极大的关注。在问题的分析中,涉及了大量策略选择问题,因而可以利用博弈论的相关原理对其进行分析研究。文章介绍了认知无线电频谱分配的一些关键问题,分析了博弈论方法在认知无线电研究中的应用条件,并阐述了认知无线电频谱分配问题的博弈论框架,为今后的相关研究起到积极的促进作用。 相似文献
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Economic Approaches for Cognitive Radio Networks: A Survey 总被引:1,自引:0,他引:1
Efficient resource allocation is one of the key concerns of implementing cognitive radio networks. Game theory has been extensively
used to study the strategic interactions between primary and secondary users for effective resource allocation. The concept
of spectrum trading has introduced a new direction for the coexistence of primary and secondary users through economic benefits
to primary users. The use of price theory and market theory from economics has played a vital role to facilitate economic
models for spectrum trading. So, it is important to understand the feasibility of using economic approaches as well as to
realize the technical challenges associated with them for implementation of cognitive radio networks. With this motivation,
we present an extensive summary of the related work that use economic approaches such as game theory and/or price theory/market
theory to model the behavior of primary and secondary users for spectrum sharing and discuss the associated issues. We also
propose some open directions for future research on economic aspects of spectrum sharing in cognitive radio networks. 相似文献
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Zhihui Shu Yi Qian Yaoqing Yang Hamid Sharif 《Wireless Communications and Mobile Computing》2016,16(14):2131-2143
In multi‐hop cognitive radio networks, it is a challenge to improve the energy efficiency of the radio nodes. To address this challenge, in this paper, we propose a two‐level Stackelberg game model, where the primary users and the secondary users act as the leaders and the followers, respectively. Based on the game model, our proposed scheme not only considers the power allocation problem for secondary users but also takes into account the price of spectrum. First, we give the cognitive radio network model, and show how to set up the game theoretic model in multi‐hop cognitive radio networks. We then analyze this problem and show the existence and uniqueness of the Nash equilibrium point for the game. We also study the impact of the spectrum price of the primary users in the cognitive radio network and study how to select the best price for the primary users to maximize their own profit. Finally, we implement simulations to show the performance of our schemes. Our work gives an insight on how to improve the energy efficiency and allocate spectrum resources in multi‐hop cognitive radio networks. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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In this paper, we propose a cognitive radio based multi-user resource allocation framework for mobile ad hoc networks using multi-carrier DS CDMA modulation over a frequency-selective fading channel. In particular, given preexisting communications in the spectrum where the system is operating, in addition to potential narrow-band interference, a channel sensing and estimation mechanism is provided to obtain information such as subcarrier availability, noise power and channel gain. Given this information, both frequency spectrum and power are allocated to emerging new users (i.e., cognitive radio users), based on a distributed multi-user resource allocation framework, in order to satisfy a target data rate and a power constraint of each cognitive radio user, while attempting to avoid interference to the existing communications as well as to minimize total power consumption of the cognitive radio users. 相似文献
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Cognitive radio and dynamic spectrum sharing systems use innovative spectrum management techniques that allow different systems to share the same frequency band to utilize the radio spectrum in an efficient way. In this paper, we propose a novel cognitive media access control protocol for cognitive radio networks under the property‐rights model, in which secondary users are divided into several nonoverlapping groups, and each group uses the proposed auction algorithm to bid for required channels from the auctioneer appointed by primary users. Simulations indicate that our proposed media access control protocol can effectively utilize spectrum resources, achieve high system efficiency, and guarantee the fairness of channel allocation among groups. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献