基于TOA预测的非同步照射辐射源定位算法

针对现有基于TDOA的定位算法难以适应辐射源信号非同步到达的实时定位问题,提出了一种基于TOA预测的非同步照射辐射源定位算法。该算法采用脉冲样本图外推法通过各站接收的短时脉冲列计算TDOA序列(TDOAs),并通过牛顿迭代法实现对辐射源位置的初步估计。对新到达的脉冲采用脉冲样本图外推法进行TOA预测,判别脉冲属性,进而获得新的TDOA测量值,然后采用扩展卡尔曼滤波算法实现对辐射源位置的实时更新。仿真分析表明:该算法解决了非同步照射引起的难以计算TDOA的问题,并增强了处理的实时性。     

重点雷达辐射源快速筛选识别算法分析

针对复杂电磁环境下辐射源识别处理时间长,高威胁等级辐射源不能及时发现的问题,研究了重点辐射源目标快速筛选识别技术,提出了一种脉冲样本图TOA差级识别算法,直接以重点辐射源的脉冲样本图为模板,与经过简单稀释后的全脉冲数据进行匹配,忽略重叠匹配优化后,得到重点目标识别结果,筛选识别同步完成,运算复杂度小,筛选识别速度快。数值仿真结果表明该方法在复杂电磁环境下能够快速有效地识别出重点辐射源,具有很高的工程应用价值。     

一种小样本数脉冲信号的样本子图分选算法

针对交错的雷达脉冲信号中,辐射源脉冲样本数较少而无法统计脉间参数规律实现脉冲提取的问题,提出了一种基于自提取样本子图的全脉冲匹配分选算法。该算法利用全脉冲移位匹配搜索自相关函数极大峰值,序贯提取辐射源时间维样本子图,同时筛选出匹配脉冲,无需对脉冲特征参数做统计分析,因此,可实现小样本数雷达信号的脉冲提取。仿真实验表明在有脉冲漏失的信号环境中,算法处理样本数充足情况下的脉冲信号与传统多参数统计方法性能相当,而且能提取出小样本数的脉冲信号。     

双星对地面未知辐射源直接定位方法研究

为解决卫星平台对地面辐射源无源定位需要参数测量导致的信号关联困难和信息损失问题,提出了一种针对未知辐射源的脉冲相参累积直接定位算法。该算法利用脉冲时差与相位差信息,通过最大似然估计原理构建代价函数实现定位。仿真分析表明,定位方法可有效应用于卫星平台,且在低信噪比条件下,可通过脉冲相参累积提升定位精度。     

一种NLOS环境下TOA与惯导信息的融合定位方法

针对基于TOA(time-of-arrival)的无线定位系统中信号容易受到非视距传播的影响等问题,提出了一种非视距条件下TOA测量与惯导信息的融合定位方法。该方法利用TOA定位结果对惯导系统进行误差抑制,同时利用惯导系统的定位结果对TOA测量进行滤波处理,进而有效地减小了非视距传播对定位结果的影响。仿真实验结果表明:该方法能提高定位精度,是NLOS环境下一种有效的定位方法。     

基于MVEKF的单站无源定位跟踪方法研究

单站无源定位是电子战中的一项重要技术。采用基于到达方向(DOA)和到达时间差(TOA)测量信息,可以实现固定观测站对运动辐射源的无源定位和跟踪。讨论了扩展卡尔曼滤波(EKF)及其改进形式修正协方差的扩展卡尔曼滤波(MVEKF)2种算法的原理,指出了应用场合和适用条件,并运用EKF和MVEKF对无源定位进行滤波估计。通过仿真,说明了2种算法的有效性,并验证了MVEKF对定位性能的改善。     

基于SPA和滑窗技术的重点雷达辐射源快速识别

在现代密集信号流中,快速识别出重点目标能为战场准备赢取宝贵的时间,并为战场提供决策依据。针对重点雷达辐射源的快速识别,提出了一种基于SPA和滑窗技术的重点雷达辐射源快速识别技术。该方法直接以经过简单预处理的全脉冲与重点雷达辐射源脉冲样本图匹配,无需传统方法的分选和特征提取过程,通过集对分析中的联系度判断脉冲对是否匹配,引入滑窗技术,缩短了处理时间。仿真表明,该方法识别准确率较高且识别速度快,具有较好的应用前景。     

基于自适应卡尔曼滤波的联合RSS/TOA/INS无人机定位算法

针对在全球导航卫星系统信号拒止环境下(如山地、隧道、峡谷)无人机集群常规定位方法受限问题,提出通过集群之间的协同定位,对卫星信号拒止的低成本无人机进行导航恢复的滤波方法,从而有效抑制纯惯性导航系统(INS)定位发散。在获取定位数据方面,首先采用基于超宽带(UWB)和Zigbee设备分别通过到达时间差(TOA)和接收信号强度(RSS)的测距方式得到测距信息,然后进一步利用最小二乘方法解算得到定位局部坐标。考虑到RSS测距远、精度低,而TOA测距精度高、测距范围小的特点,提出一种基于TOA/RSS/INS的序贯扩展卡尔曼滤波算法,通过引入自适应因子,为短程定位信息提供TOA/RSS两路定位冗余的同时,在长程TOA定位失效时仍可利用RSS定位来抑制惯性导航的发散。实验结果表明,该算法在近程可由RSS/TOA提供冗余测距信息,通过自适应因子可将定位精度改善至2m;在长程,尤其TOA定位失效的范围外,同样可以提供误差约为5m的定位信息。相对于传统扩展卡尔曼滤波,所提出的自适应序贯卡尔曼滤波算法有效提高了定位精度,为解决传统定位受限条件下的基于无人机无线电定位研究提供新的思路。     

基于方向角及其变化率测量子集的单站无源定位

根据目标辐射源的方向角及其变化率信息所构成的不同测量子集及建立的目标测量模型,提出了一种基于数据融合的优化定位处理方案,对各个单测量子集所得到不同的目标位置及测量误差值进行数据融合处理,分析比较了多测量子集融合处理后与单测量子集的定位性能,仿真分析表明,该优化定位处理方案可有效地提高无源探测系统的目标定位精度,减小探测盲区.     

多站时差与多参数联合分选定位方法

多站电子侦察系统中,两个观测站接收到的脉冲信号到达时间差可以用于分选和定位。针对复杂信号脉间信息关联性弱,不能对脉冲数极少的信号进行分选的问题,提出一种多站时差与多参数联合分选定位新方法。该方法利用时差窗先验信息,将主站和所有副站脉冲同时进行多站时差和多参数联合预分选,并将预分选结果按位置进行融合,得到最终分选和定位结果,能对脉冲数极少的信号进行分选定位,甚至可实现单个脉冲的分选定位。仿真结果表明了该方法的有效性。     

Putin – the masked nemesis of the strategy of ambiguity

Recent events demonstrate the complex and adaptive approach employed by Russia to reassert influence in Europe. The changing face of Russia’s strategy commenced in 2007 when it launched a crippling cyber-attack against Estonia. This was followed by a large Russian conventional attack against Georgia in 2008, occupying two large areas of the nation. 2014 witnessed the Russian annexation of Crimea where in just a week, Russia seized control of Crimea “without firing a shot.” The annexation of Crimea was rapidly followed by a Russian inspired and led subversive war in eastern Ukraine. The common thread among these diverse Russian operations is its use of ambiguity to confound and confuse decision makers in the West.     

India's counter-insurgency experience: the ‘trust and nurture’ strategy

The Indian Army, a force trained primarily for conventional warfare, has been engaged in internal counter-insurgency operations since the 1950s. Despite such a long innings on a counter-insurgency mode, little attention has been accorded within military circles to doctrinal innovation for waging sub-conventional warfare in India's democratic political context. At best, the Army continues to view counter-insurgency duty as secondary to its primary duty of defending India from external conventional threats. By conceptualizing a counter-insurgency strategy of ‘trust and nurture’, this article aims to fill this critical doctrinal gap in India's military policy. The author argues that a counter-insurgency strategy of ‘trust and nurture’ based on democratic political culture, measured military methods, special counter-insurgency forces, local social and cultural awareness and an integrative nation-building approach will result in positive handling of India's internal security problems. The author utilizes India's counter-insurgency experiences in Assam, Mizoram, Nagaland, Punjab, and Operation ‘Sadhbhavana’ in Jammu and Kashmir as illustrative empirical indicants in order to validate the ‘trust and nurture’ strategy.     

Helping hands: civil–military cooperation and Italy's military operation abroad

In the Post-Bipolar Era the growing complexity of the military operations requires a new approach for the resolution of international crises. Since the end of the Cold War, peace support operations (PSO) have become the mainstay and principal occupation of most Western armies. At the same time, Italy has been one of the most important actors in such an area. The article focuses on the cooperation between military and civil components (a process called CIMIC) as a key variable in the Italian PSOs. We will analyse in detail the main lessons learned from past military interventions as well as the general context in which new tendencies are taking place. The maintaining of a minimum security frame becomes essential to fulfil activities ‘collateral’ to the mission: reconstructing services and infrastructure, food distribution, water and medication, law and order, de-mining, training of local forces, and supporting local institutions. These are the main tasks to obtain thrust and support from the population.     

Terrorism,insurgency, kidnapping,and security in Africa's energy sector

Energy continues to serve as the bedrock of modern economies and the main driver of modern society. For Africa, the production and supply of energy resources such as crude oil, natural gas, uranium, coal, biomass, biofuels and other renewables are an important source of employment, rents, taxes, royalties and profits. This sector brings in several tens of billions of dollars of revenue annually. The production and delivery of such resources, however, depend on critical infrastructures such as pipelines, refineries, processing plants, terminals, rigs, electrical energy pylons, substations, pump stations, vessels, and tankers. These infrastructures have been attacked by terrorists, insurgents, vandals and saboteurs, all of whom see them as targets against which to register their grievances and extract concessions from the state. This paper is a chronological account of some of the documented incidents of terrorism, insurgency, kidnapping, destruction, sabotage, and human casualties suffered in the oil and gas sectors in Africa between 1999 and 2012. It is based on data extracted from the databases of the RAND Database of World Terrorism Incidents and the University of Maryland's Global Terrorism Database (GTD).     

Tacit support for terrorism: The rapprochement between the USSR and Palestinian guerrilla organizations following the 1967 war

This article demonstrates the inconsistent and wavering Soviet attitude towards national liberation movements in general and the Palestinian organizations in particular. Until the late 1960s, the Soviets viewed these organizations with suspicion, hesitating to engage in political dialogue with them. However, in the 1970s, political and military events in the region, as well as modifications in the Kremlin's Cold War strategies, led to a general shift towards the Middle East in Soviet foreign policy. Soviet leaders showed increased willingness to provide certain Palestinian organizations with arms with which to conduct terrorist activities against Israeli, pro-Israeli, Jewish and Western targets. The article explores the complex relations between Palestinian organizations and the USSR in the field of international terror. The study also exposes and analyzes the nature and content of Soviet–Palestinian arms dialogues and transactions. It provides clear evidence that Soviet policymakers and other luminaries were fully informed of, and sometimes directly involved in, these transactions and dialogues at the highest levels.     

A1 Qaeda and the radical Islamic challenge to western strategy

The September 11 global crisis prompted by the attacks on the World Trade Center and the Pentagon raises major questions concerning the nature and trajectory of terrorism in the post-Cold War global order. Hitherto, terrorism has been largely debated by analysts at the level of nation states. Terrorist and insurgent movements have also been largely anchored in nationalist and ethnic power bases even when they have sought to mobilise a transnational ideological appeal on religious or class grounds. There have been a few exceptions to this pattern such as the alliance between the German Baader-Meinhof group and the Japanese Red Army Faction, but even such international alliances as this did not, until at least the 1980s, presage anything like a global terrorist network necessitating a global strategic response. This study examines terrorism and global strategic responses.     

Helping hands: external support for the KNU insurgency in Burma

This article analyses to what extent the Burmese KNU insurgency made use of external support from states, refugees, and diasporas. Based on extensive fieldwork it is concluded that support from neighbouring states and refugees has for years kept the Karen rebellion alive. Western countries perceived forms of resistance to the illegitimate Burmese regime as just and have therefore played a crucial role in the continuation of conflict in Karen State. It is important that policymakers and donors as well as executing organizations continue to reflect critically on the way they exercise their work.     

Reviews

Douglas S. Derrer, We Are All the Target: A Handbook of Terrorism Avoidance and Hostage Survival. Annapolis, MD: US Naval Institute Press, 1992. Pp. x+135, notes, index. $14.95. ISBN 01–55750–150–5

Ian Knight, Zulu: Isandlwana and Rorke's Drift, 22–23 January 1879. London: Windrow & Greene, 1992. Pp.136, 150 illus., incl 8 colour plates, maps, biblio. £35. ISBN 1–872004–23–7

Ian Knight, By the Orders of the Great White Queen: Campaigning in Zululand through the Eyes of the British Soldiers, 1879. London: Greenhill Books and Novato: Presidio Press, 1992. Pp. 272, 17 illus., 1 map. £18.95. ISBN 1–85367–122–3

Manfried Rauchensteiner and Erwin A. Schmidl (eds.), Formen des Krieges: vom Mittelalter zum ‘Low‐intensity’ Conflict’. Graz : Verlag Styria, 1991. Pp.208. DM35. ISBN 3–22–12139–7

Harold J. Kearsley, Maritime Power and the Twenty‐First Century. Dartmouth: Dartmouth Publishing Company, Limited, 1992. Pp.xv + 203, 13 diagrams, index. £32.50. ISBN 1–85521–288–9     

基于GTST-DMLD-ESD的装备RMS建模仿真

装备的RMS是装备的重要设计参数,是影响战备完好和保障能力的关键因素.引入GTST-DMLD作为主要建模工具,建立起装备系统的RMS描述模型,以ESD为补充和扩展,对维修过程进行建模.并以GTST-DMLD-ESD模型作为装备RMS仿真的核心,对装备RMS仿真模型的总体框架进行了研究,并对各模块进行了较为详细的探讨.