GNSS自适应天线相位中心评估方法

自适应天线在波束形成过程中会引起天线相位中心变化,针对这一问题,提出一种基于可用波束的自适应天线相位中心评估方法。该方法分为三步:设置天线的可用波束门限;在干扰来向均匀分布下,得到天线可用波束门限内相位方向图集合;利用最小二乘法对相位方向图集合进行拟合得到自适应天线的平均相位中心变化量。运用该方法对四种典型的四元阵相位中心进行对比仿真,结果表明,算法可以快速有效地对自适应天线相位中心性能进行评估。另外,通过设置适当的可用波束门限,可以提高自适应天线的相位中心性能。算法的评估结果可以作为GNSS高精度自适应天线阵型选择依据。     

小型旋翼无人机在未来城市军事行动应用中潜力评估

随着全球范围的城市化进程不断推进,未来军事斗争向城市环境中发展是必然趋势。在城市作战需求分析的基础上,剖析了传统装备的"城市病",阐述了小型旋翼无人机在城市军事行动中的应用潜能。研究表明,针对现有装备在城市作战中显示出的若干短板,发展基于小型旋翼无人机打造侦察平台与精确打击平台将是一个较好的解决方案。而运用军民融合的发展模式挖掘小型旋翼无人机军用潜力,在提升军队作战能力,降低成本均具有积极意义。     

舰炮对海上集群小目标射击的毁伤概率

海上集群小目标是水面舰艇面临的主要威胁之一。以单管大口径舰炮对海上集群小目标射击作为研究对象,对集群目标进行了等效处理,分析了弹种、引信和装药的选择以及效力射中的表尺分配问题,提出多表尺效力射方法,利用该方法对海上集群小目标射击的毁伤概率进行了分析。结果表明,采用该方法并使用空炸榴弹或杀伤爆破弹,可有效破坏敌运输工具,杀伤其有生力量。     

Landmines and Conservation in Southern Africa: Peace Parks in the Aftermath of Armed Conflict

Peace parks are a modern means of conflict resolution through nature conservation. The Great Limpopo Peace Park (GLPP), which spans South Africa, Zimbabwe and Mozambique, was established to bring new hope to an area that is infamous for racial and political divisions, civil war and widespread poverty. This paper discusses the impact of international laws governing landmines, the current priority choices of the countries involved, and the situation in the two mine-affected countries: Mozambique and Zimbabwe. Minefields and politics are interrelated, and have an impact at local, national and international level. Using the GLPP as a case study, the article argues that although they have been presented as excellent examples of integrated biodiversity conservation and socio-economic development in developing countries, peace parks will not fulfil their main objective of promoting an image of peace in the aftermath of conflict without addressing landmine contamination.     

Callwell versus Graziani: how the British Army applied ‘small wars’ techniques in major operations in Africa and the Middle East, 1940–41

The period from December 1940 through to the spring of 1941 saw the British Army win a series of rapid and decisive victories over Italian and Vichy French forces in North and East Africa and the Middle East. A key feature of these operations was the extensive British use of fast-moving all-arms mobile formations utilising superior speed and mobility to out-manoeuvre considerably larger Italian formations. A number of reasons have been given for the British Army adopting this mode of warfare, but the paper contends that the best explanation is that they were an organic evolution from methods used by the British Army in ‘small wars’ throughout the early twentieth century, use of mobile ‘frontier columns’ at the operational and tactical level of war being described and recommended by Callwell himself and visible with the Army in practice in operations in India and the Middle East in particular. The inter-war period saw the combination of this model of warfare with post-First World War military technology, notably tanks, close air support and coordination by wireless. Colonial operations in this period also saw some utilisation of what would later be identified as ‘Special Forces’ – also used extensively in the Desert War – the most obvious example being Captain Orde Wingate's Special Night Squads in Palestine in 1938.     

Maritime interdiction in Sri Lanka's counterinsurgency

A comprehensive maritime interdiction strategy to attack the insurgent's logistic system was a key element in the defeat of the Tamil Tigers. The campaign of maritime interdiction required the Sri Lankan Navy (SLN) to attack LTTE arms smuggling, sea piracy, and maritime terrorism. The SLN degraded the insurgency's robust maritime logistical network while also devising tactics to engage the maritime insurgents who reacted with swarm and suicide boat tactics. The efforts of the SLN forced the Tamil Tigers to confront the government's final land offensives with diminished resources, thus collapsing a three decades’ old insurgency in a matter of months.     

GTEM室内脉冲场分析及对数周期天线的响应规律研究

为研究对数周期天线(LPGA)的方波脉冲响应特性,利用GTEM室和CST仿真软件对LPGA方波脉冲响应信号进行实验测试与仿真分析.利用实验室自行研制的超宽带电场测试系统对GTEM室进行校准,得到了室内电场强度E(t)与方波源的输出电压V(t)和芯板高度h之间的关系;搭建GTEM室中天线脉冲响应测试平台,得到不同辐照方向下的LPGA方波脉冲时域响应信号;利用CST仿真软件建立对数周期天线的3D模型,得到响应信号幅值的开路电路模型.     

The sixteenth-century antecedents of special operations ‘small war’

The first conceptual, theoretical treatises about small war (la petite guerre) as special operations appeared only from the middle of the seventeenth century. The term is not used in the eighteenth-century sense of ‘special operations’ in older sources. The supposed absence of any treatment of the subject is surprising considering the obsession with the ‘art of war’ in the Renaissance, but other authors attribute it to a supposed antinomy between chivalric ideals and irregular warfare. But the absence of explicit manuals on the subject is not evidence of absence of advanced reflection on this kind of operations in the Middle Ages and in Early Modern times. We should thus look elsewhere, in other genres, for writings that contain and pass on military knowledge. Epics, romances, educational and military treatises, and memoirs in fact contain elements of a theory of special operations, even though these genres differ from our conception of rationality inherited from the Enlightenment.     

Introduction: Exploring the jungle of terminology

When twentieth-century authors wrote about ‘partisan warfare’, they usually meant an insurgency or asymmetric military operations conducted against a superior force by small bands of ideologically driven irregular fighters. By contrast, originally (i.e. before the French Revolution) ‘partisan’ in French, English, and German referred only to the leader of a detachment of special forces (party, partie, Parthey, détachement) which the major European powers used to conduct special operations alongside their regular forces. Such special operations were the classic definition of ‘small war’ (petite guerre) in the late seventeenth and in the eighteenth centuries. The Spanish word ‘la guerrilla’, meaning nothing other than ‘small war’, only acquired an association with rebellion with the Spanish War of Independence against Napoleon. Even after this, however, armies throughout the world have continued to employ special forces. In the late nineteenth century, their operations have still been referred to as prosecuting ‘la guerrilla’ or ‘small war’, which existed side by side with, and was often mixed with, ‘people's war’ or popular uprisings against hated regimes.     

机载共形UHF天线的设计与仿真

机载全向天线不但要满足水平面全向的指标要求,而且要与机体表面共形设计,常规的单极子天线和微带天线均无法满足要求。本文设计了一种机栽环形缝隙天线,实现了天线小型化和机载共形。该天线结构简单,满足VSWR〈1．4的频带宽为350～376MHz,满足VSWR〈2的频带宽为338-438MHz,且工作频率范围内的最大增益达到4．2dB。