基于无线信道的物理层密钥生成与协商技术研究

发布时间：2018-06-04 23:17

本文选题：无线信道 + 物理层安全　；参考：《南京邮电大学》2017年硕士论文

【摘要】：近年来,随着无线通信的飞速发展,人们享受着高新技术所带来的前所未有的便捷。同时由无线媒介的广播性和开放性所面临的安全及隐私隐患,也严重影响着人们的生活,成为了学者研究的重点。传统保障安全通信的技术由于量子时代的到来,传统的加密方法很容易被破解。物理层密钥生成技术的出现能够避免了传统加密技术中因密钥分发而引起的泄密风险,由于其充分利用通信双方无线通信信道的互易性与时变性,不仅可以实现“一次一密”的动态密钥生成,而且无需进行密钥分发,达到信息理论意义上的安全。本文针对大多数仅从单一的信道特征来考虑生成密钥,在信道特性变化的场景下,可能存在适应性不强、初始密钥一致率较低等问题。本文提取无线信道中的信道幅度和信道相位信息联合生成密钥,对初始密钥生成的误比特率、随机性以及密钥容量等方面进行研究,主要的研究工作如下:(1)对基于无线信道特征的物理层密钥生成方法进行了回顾与总结,并比较了各自优缺点。针对通信双方初始生成密钥的不一致性问题,研究了密钥协商体系模型,从信息调和、一致性认证、保密增强这三个方面归纳总结了一些典型的技术和算法,并对比分析了其优缺点。(2)基于窄带平坦衰落信道,提出了一种联合信道幅度和相位的二维无线物理层密钥生成方法,该方法将估计出来的信道幅度和信道相位组合成一个极坐标点进行量化。仿真结果表明,与纯相位生成密钥的方法相比,本方法具有更低的初始密钥不一致率。(3)在窃听信道系统模型的基础上,借助随机变量以及信息熵的概念与性质,推导了基于通信双方信道幅度和信道相位的密钥容量,并以此作为理论基础,设计了一种自适应多比特密钥生成方案。仿真结果表明,该方案在生成速率和误比特率之间实现了折衷。
[Abstract]:In recent years, with the rapid development of wireless communication, people enjoy unprecedented convenience brought by high-tech. At the same time, the hidden dangers of security and privacy, which are faced by the broadcast and openness of wireless media, also seriously affect people's lives and become the focus of scholars' research. The traditional secure communication technology is easy to be cracked because of the arrival of quantum age. The emergence of physical layer key generation technology can avoid the risk of leakage caused by key distribution in traditional encryption technology, because it makes full use of the reciprocity and time-varying of wireless communication channel between the two sides of the communication. It can not only realize the dynamic key generation of "one secret at a time", but also achieve the security in the sense of information theory without the need for key distribution. In this paper, we consider the generation of keys only from a single channel feature. In the scenario of channel characteristics change, there may be some problems such as low adaptability and low initial key consistency rate. In this paper, the channel amplitude and channel phase information are extracted from the wireless channel to generate the key, and the bit error rate, randomness and key capacity of the initial key generation are studied. The main research work is as follows: (1) the physical layer key generation methods based on wireless channel features are reviewed and summarized, and their advantages and disadvantages are compared. Aiming at the inconsistency of the initial key generation between the two communication parties, the key agreement system model is studied, and some typical techniques and algorithms are summarized from the aspects of information reconciliation, consistency authentication and security enhancement. Based on narrow band flat fading channel, this paper proposes a two-dimensional physical layer key generation method combining channel amplitude and phase. In this method, the estimated channel amplitude and phase are combined into a polar coordinate point for quantization. The simulation results show that compared with the pure phase key generation method, this method has a lower initial key inconsistency rate. It is based on the eavesdropping channel system model, with the help of random variables and the concept and properties of information entropy. The key capacity based on channel amplitude and channel phase is derived, and an adaptive multi-bit key generation scheme is designed. Simulation results show that the proposed scheme achieves a tradeoff between the generation rate and the bit error rate.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN918.4

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