频谱感知链路干扰与抗干扰研究

发布时间：2018-03-24 18:22

本文选题：频谱感知　切入点：感知链路干扰　出处：《电子科技大学》2017年硕士论文

【摘要】：频谱感知是一个实时检测授权频段使用状态的过程。次级用户利用频谱感知可实时观测目标频段的状态。这使得次级用户机会性接入授权频段和避免干扰主用户成为可能。但是,恶意用户通过在次级用户的频谱感知过程中发射干扰信号,增加次级用户对其所处环境中频谱使用状态做出误判的概率,降低目标系统的频谱利用率。恶意用户在目标次级用户的感知链路中,主动发射干扰信号的方式,称为感知链路干扰。本文针对感知链路的干扰问题,从如何实施最优干扰、如何对抗感知链路干扰这两个方面,分别展开了研究。首先,针对干扰机的不同地理位置,对目标次级用户的感知性能影响相应不同的问题,研究了干扰机的最优干扰位置。具体而言,以最大化次级用户网络的平均误检概率为目标,分水平位置固定、水平位置可变两种情况,从理论上给出了干扰机的最优干扰位置,探讨了不同干扰功率、不同次级用户数量对最优位置影响的规律,并通过计算机仿真进行了验证。另一方面,论文针对重放攻击,研究了如何对抗感知链路干扰的问题。提出一种基于哈希验证码的抗干扰策略。推导了所提方法在重放攻击存在环境下的抗干扰性能。计算机仿真表明,在多种场景下,所提出方法的感知链路抗干扰性能优于现有方法。本文对感知链路最优干扰位置以及感知链路抗干扰策略的研究,丰富了现有的频谱感知理论,为设计安全可靠的频谱感知系统提供理论依据。
[Abstract]:Spectrum sensing is a process of detecting the state of authorized frequency band in real time. Secondary users can use spectrum sensing to observe the state of target frequency band in real time. This enables secondary users to access the authorized frequency band opportunistically and avoid interfering with primary users. It's possible. But, Malicious users transmit interference signals in the process of spectrum sensing of secondary users, thus increasing the probability of secondary users making misjudgment of spectrum usage status in their environment. The way that malicious users actively transmit interference signals in the target secondary users' perceptual links is called perceptual link interference. This paper aims at the interference problem of perceptual links and discusses how to implement optimal interference. How to counteract the perceptual link interference is studied separately. Firstly, aiming at the different geographical location of the jammer, it affects the perceived performance of the target secondary user. In this paper, the optimal jamming position of the jammer is studied. Specifically, aiming at maximizing the average false detection probability of the secondary user network, the optimal jamming position of the jammer is given theoretically, in which the horizontal position is fixed and the horizontal position is variable. The influence of different interference power and number of secondary users on the optimal position is discussed and verified by computer simulation. On the other hand, the paper aims at replay attack. In this paper, the problem of how to counteract perceptual link interference is studied, and an anti-jamming strategy based on hash verification code is proposed. The anti-jamming performance of the proposed method in the presence of replay attack is deduced. Computer simulation shows that, in many scenarios, The performance of the proposed method is better than that of the existing methods. In this paper, the research on the optimal interference location of the perceptual link and the anti-jamming strategy of the perceptual link enriches the existing spectrum sensing theory. It provides a theoretical basis for the design of a safe and reliable spectrum sensing system.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN97

【参考文献】