地线设计在PCB电磁兼容性中的作用

简介了电磁兼容性(EMC)的基本概念,并结合某项目实际应用,说明地线设计的一点改变即可在PCB电磁兼容方面起到重要作用.     

防空武器系统火力兼容模型研究

基于防空武器系统协同抗击时可能出现的弹道交叉现象,根据防空导弹与火炮武器系统的火力兼容要求,结合对空域和时域特点的分析,建立防空导弹与火炮武器协同使用时的火力兼容模型,并对所建火力兼容模型进行简化和分析,为深入研究防空武器系统协同使用时的火力兼容问题提供理论依据.     

Source localization using a non-cocentered orthogonal loop and dipole （NCOLD） array

A uniform array of scalar-sensors with intersensor spacings over a large aperture size generally offers enhanced resolution and source localization accuracy,but it may also lead to cyclic ambiguity.By exploiting the polarization information of impinging waves,an electromagnetic vector-sensor array outperforms the unpolarized scalar-sensor array in resolving this cyclic ambiguity.However,the electromagnetic vector-sensor array usually consists of cocentered orthogonal loops and dipoles（COLD）,which is easily subjected to mutual coupling across these cocentered dipoles/loops.As a result,the source localization performance of the COLD array may substantially degrade rather than being improved.This paper proposes a new source localization method with a non-cocentered orthogonal loop and dipole（NCOLD）array.The NCOLD array contains only one dipole or loop on each array grid,and the intersensor spacings are larger than a half-wavelength.Therefore,unlike the COLD array,these well separated dipoles/loops minimize the mutual coupling effects and extend the spatial aperture as well.With the NCOLD array,the proposed method can effciently exploit the polarization information to offer high localization precision.     

利用建模工具软件进行系统间电磁兼容性预测分析——性能预测

通过对实际USB系统射频部分的建模和仿真，探讨利用工具软件进行电磁兼容性预测分析——性能预测。     

A type of 2D magnetic equivalent circuit framework of permanent magnet for magnetic system in AEMR

Modeling of permanent magnet(PM) is very important in the process of electromagnetic system calculation of aerospace electromagnetic relay(AEMR). In traditional analytical calculation, PM is often equivalent to a lumped parameter model of one magnetic resistance and one magnetic potential, but great error is often caused for the inner differences of PM; based on the conception of flux tube, a type of 2D magnetic equivalent circuit framework of permanent magnet model(2D MECF) is established; the element is defined, the relationship between elements is deduced, and solution procedure as well as verification condition of this model is given; by a case study of the electromagnetic system of a certain type of AEMR, the electromagnetic system calculation model is established based on 2D MECF and the attractive force at different rotation angles is calculated; the proposed method is compared with the traditional lumped parameter model and finite element method(FEM); for some types of electromagnetic systems with symmetrical structure, 2D MECF proves to be of acceptable accuracy and high calculation speed which fit the requirement of robust design for AEMR.     

空客飞机维修中的润滑脂使用问题

通过对空客服务信函SIL12-008出台背景及相关知识的探讨，分析了飞机维修中润滑脂的相容性问题，并对如何避免润滑脂的混用提出建议。     

电磁带隙结构测量的悬置微带线法研究

对用于测量电磁带隙（Electromagnetic Band Gap,EBG）结构带隙中心频率和带隙宽度的悬置微带线法进行仿真和实验研究。通过对不同高度和不同宽度的悬置微带线进行仿真,研究悬置微带线的高度和线宽对EBG带隙中心频率、带隙宽度测量值的影响。最后以蘑菇型EBG结构为例,进行了实物加工和测试验证。     

冷冻强力吸盘的设计及研究

目的设计制作一种由电子制冷系统、温度控制系统、水冷系统和装夹工作台构成的冷冻强力吸盘。方法通过电子制冷器迅速降低或升高工作台的温度,可以达到粘结、固定工件或拆卸工件的目的。结果该装置的核心技术是使用半导体制冷技术,采用全电子控制,它既可应用于各种磁性材料工件的装夹,也可应用于各种非磁性材料工件的装夹。结论该装置性能可靠,快速高效,操作简单。     

全红外光激发里德堡原子微波电场测量

基于高激发里德堡原子的微波电场测量技术与传统金属天线相比有诸多优越性,是未来微波电场高精度测量的重要方案之一。采用全红外光激发里德堡原子的方案不再依赖复杂而昂贵的短波长激光器,大大减小了激光器系统的体积与能耗。在三红外光级联激发里德堡铷原子的过程中,发现了中间态对应的双光梯形电磁诱导透明光学参数对三光激发里德堡态电磁诱导吸收峰信噪比具有重要影响,因此采用光失谐方法能很好地优化三光EIA光谱。利用微波场下的Autler-Townes分裂效应和标准天线方法对微波喇叭天线发射的微波电场实现精确的校准,并以此为基础通过超外差接收技术成功探测到本地场与信号场所形成的拍频信号,得到了拍频光电信号与信号场强度之间的线性关系。最终通过实验噪声基底的噪声功率谱得到三红外光里德堡铷原子微波测量的极限灵敏度为37.5(5.5) nV·■。采用三束红外光激发的方法为研制小型里德堡原子微波电场探测仪器奠定了物理基础。     

返回式卫星的供配电系统

供配电系统是卫星的一个重要分系统。卫星飞行任务的圓满完成,依赖于供配电系统的正确和可靠地工作。供配电系统包括电源的产生、电源的分配和控制、电源的贮存和电缆网等。文章首先讨论返回式卫星的任务和特点,然后给出供配电系统的设计方法。特别对配电准则、配电方案(集中制、分散制和混合制)和配电器的设计作了详细的描述。