同时收发认知抗干扰系统的改进能量检测算法

为增强复杂电磁环境中同时收发认知抗干扰通信系统的性能,研究了基于该系统的改进能量检测算法,推导出瑞利衰落信道中系统的检测概率、虚警概率及中断概率的理论表达式。该改进方法思想是将自干扰信道容量与接收机所需传输速率进行比较,通过比较结果确定能量检测门限值。仿真结果表明,改进能量检测算法能够有效地降低自干扰信号对同时收发认知抗干扰接收机的不利影响,提升系统的中断性能。     

协同作战中信息分发算法研究

大规模协同作战中的高效通信问题为当前信息战的研究重点之一,但由于单独作战单元无法了解全局的信息内容及需求方,这给通信资源有限的参战兵力之间的态势共享带来了困难。为此提出了一个分布式协作信息分发算法,在理论上借鉴了复杂网络的小世界特性,即单元节点可以通过邻节点在较少跳数内完成信息的传输。在思路上利用了信息相关性概念,作战单元利用信息之间的关联性及信息与节点之间的收发关系建立控制信息发送的路由表。并通过仿真实验验证了不同网络拓扑下算法性能的变化情况,结果证明分发算法能较好地支持信息共享。     

Nuclear deterrence and cyber warfare: coexistence or competition?

Nuclear deterrence and cyber war seem almost antithetical in their respective intellectual pedigrees. Nuclear weapons are unique in their ability to create mass destruction in a short time. Information or “cyber” weapons, at least for the most part, aim at sowing confusion or mass disruption instead of widespread physical destruction. Nevertheless, there are some intersections between cyber and nuclear matters, and these have the potential to become troublesome for the future of nuclear deterrence. For example, cyber attacks might complicate the management of a nuclear crisis. As well, information attacks on command-control and communications systems might lead to a mistaken nuclear launch based on false warnings, to erroneous interpretations of data or to panic on account of feared information blackout. It is not inconceivable that future nuclear strike planning will include a preliminary wave of cyber strikes or at least a more protracted “preparation of the battlefield” by roaming through enemy networks to plant malware or map vulnerabilities.     

Explaining Cohesion in an Insurgent Organization: The Case of the Mizo National Front

Despite the prevalence of violent uprisings against the states, existing literature has produced a generalized explanation of the causes and onset of such uprisings ignoring crucial aspects of (non-state) armed group cohesion, such as their capabilities to manage intra-group tensions and rivalries. In this paper, I examine recent research in the field of civil conflict to understand the importance of investigating underlying constraints which can cause serious impediments to the capabilities of a state during the course of a war. The paper then focuses on the importance of internal strategic resources, such as pre-war and wartime sociopolitical networks in which insurgents mobilize, recruit new cadres and maintain intra-group cooperation, to suggest how it can contain the consequences of counterinsurgency operations and other state strategies on the internal cohesion of an insurgent group. A detailed case study of the Mizo National Front (MNF) in India demonstrates the argument’s plausibility.     

基于物联网的战地装备安全监管问题研究

针对战地环境中军事装备的安全监管问题,分析了战地装备安全监管应用系统的整体结构与功能层次,给出了基于RFID射频识别技术、无线传感器等物联网技术的硬件平台设计方案,以及基于数据采集、分析、融合、传输和可视化技术研发监管控制软件的实现方案。该系统部署应用后可实现对装备实时、连续、精确的分级监管,能够确保装备管理的安全和高效,提高部队指挥决策能力。     

Covert radio communications: a viable tactic for international terrorists?

Covert operations by underground groups, such as transnational terrorists, are not new and neither are the methods members of these groups use to communicate in their shadowy world. In this regard, one of the enduring myths is that the main means these covert operatives use to communicate within their cell structure are telephones and emails in their various manifestations. This article critically discusses the possible use of wireless transmissions by transnational terrorists as a reliable form of communications. To critically discuss this proposition, a force field analysis was used to assess the theory that radio is a viable option. Implications of this study's findings are considered in terms of the ramifications they have for defence and security policy.     

无线传感器网络DV-Hop节点定位改进算法

针对无线传感器网络中距离无关类节点定位算法定位误差较大的问题,提出了一种改进型DV-Hop节点定位算法。通过设置待定位节点到信标节点间的最小跳数门限,降低了定位累积误差;改进了平均每跳距离估计方法,并利用信标节点测量的位置误差作为修正值,对每跳距离的估计值进行修正;待定位节点仅选取与之较近的信标节点计算位置,降低了距离误差。仿真结果显示,在信标节点比例和网络节点总数相同的条件下,改进算法性能明显优于DV-Hop算法。     

THO-MAC:一种两跳优化的低延迟低功耗无线传感器网络介质访问控制协议

功耗与延迟是无线传感器网络介质访问控制协议设计首要考虑的两个问题。提出了一种新的传感器网络低延迟、低功耗、接收节点初始化异步介质访问控制协议——THO-MAC协议。通过准确预测接收节点的唤醒时间,THO-MAC协议调度发送节点侦听信道,从而减少发送节点空闲侦听能量浪费。THOMAC协议在发送节点两跳转发节点集中选择使报文两跳转发延迟最小的转发节点,从而降低报文传输延迟。使用NS2模拟器对THO-MAC协议进行了详细模拟。模拟结果显示,与RI-MAC和Any-MAC协议相比,THOMAC协议可以减少35.5%和18%的报文传输延迟,同时节省23.5%和15.5%的节点功耗。     

动态拓扑图的卫星网络可视化方法

针对高度动态变化的卫星网络,提出一种基于动态拓扑图的可视化方法。动态拓扑图可视化的难点在于如何保持动态可视化过程中的稳定性,从而使用户容易地感知到网络中所发生的拓扑变化。根据卫星网络的动态变化特点,构建连续的动态拓扑图模型;设计一种保持布局稳定性的策略,并基于力引导思想提出一种动态拓扑图布局算法;以Iridium系统为典型实例,验证本文的可视化方法的合理性和可行性。实验表明,该方法能够以清晰的可视化图像支持用户对卫星网络动态拓扑的感知和理解。     

低速率移动自组织网络安全路由协议

由于移动Ad Hoc网络具有无需基础设施,可以快速部署,很难完全被摧毁等优点,被作为数字化战场通信的优先选择,设计实现了一种适用于低速率移动Ad Hoc网络的安全路由协议——LSRP,它适用于分层架构的低速移动电台自组网,可以在网络资源有限的情况下,防御来自外部和内部两方面的攻击。LSRP协议利用分布式门限RSA签名方案来阻止非授权接入,防范来自网络外部的攻击;利用邻节点信任度评估机制,进行恶意节点检测和剪除,防范来自网络内部的攻击,增强了网络的安全性。