滚仰式红外导引头视线角速率提取方法研究

由于滚仰式导引头的结构特殊性,制导控制系统需要的视线角速率信息是不能够直接测量得到的,因此提出了一种基于跟踪微分器的视线角速率提取方法。根据滚仰式导引头的结构特点,分析了滚仰式导引头的运动学原理,并根据滚仰式导引头的结构推导出视线角与弹体姿态角、框架角和失调角的关系,然后设计了有限时间收敛跟踪微分器求解视线角速率信息。经数字仿真,对比了直接差分法和跟踪微分器法对视线角速率的提取效果,证明了利用跟踪微分器提取视线角速率的有效性。     

基于跟踪微分器的滚仰式成像导引头视线角速率估计

针对滚仰式半捷联成像导引头难以直接获得精确的视线角速率这一问题,提出利用弹体姿态角速率、失调角、框架滚仰角等信息解算出惯性系下的视线角的方法。针对解算出的惯性系下的视线角,通过选择合适的跟踪微分器提取出惯性系下的视线角速率信息。仿真试验表明,选择合适的跟踪微分器能够在大背景噪声下对惯性系下解算出的视线角连续平滑地微分,进而可得到精确的视线角速率。     

全捷联导引头视线角速度STCKF提取技术

传统的平台导引头可以通过物理跟踪回路直接提取导弹制导所需的视线角速度信息,采用全捷联结构后,导引头失去了直接测量视线角速度的能力,视线角速度需要通过数字计算的方法来提取。针对全捷联导引头精确制导技术工程应用中的问题,首先给出了视线角速度提取方案,推导得到视线角速度估计模型,鉴于估计模型的强非线性,采用强跟踪容积卡尔曼滤波算法对视线角速度进行估计。结合小型空面导弹的典型使用条件,通过弹道仿真对视线角速度估计算法的有效性进行了验证。仿真试验表明:导引头在末制导段捕获目标后,能迅速消除滤波初始误差,准确跟踪真实的弹目视线角和视线角速度变化。为验证将滤波输出作为制导信息的可行性,考虑激光半主动全捷联导引头的典型干扰,用蒙特卡洛打靶方法对导弹制导精度进行了考核,1 000次打靶结果显示,对静止目标的制导精度为0.58 m（CEP）,对运动目标的制导精度为0.84 m（CEP）,满足精确制导武器的制导精度要求。     

动力陀螺式导引头跟踪能力分析

动力陀螺式导引头（下文中简称导引头）的跟踪能力是影响制导精度的主要因素之一。为分析导引头跟踪能力,定义了导引头跟踪能力性能指标。通过建立导引头的耦合动力学模型,对稳像及跟踪能力的传递函数及动力学模型稳定性进行解析和频域分析。从动力学稳定性的角度得出了限制导引头跟踪能力的根本原因。通过对比导引头半实物仿真与数学仿真结果,验证了动力学模型的精确性。为减小稳态失调角,提高导引头的跟踪能力,提出了PI校正,仿真分析发现通过调整比例积分系数可以达到减小失调角并且不降低其他性能指标的目的。进一步探讨了在导引头失调角为0时目标视线角速度信息的提取方法。此文可以为导引头动力学及控制系统设计提供指导。     

成像导引头光轴与视线之间相对运动的研究

视线在惯性空间中运动所形成的角速度是导引头输出的重要的制导信息。从运动学的角度将视线在惯性空间的运动分解成视线相对导引头光轴的运动和光轴相对惯性空间的运动。基于刚体定点转动理论,分析了目标在导引头视场中运动时视线相对光轴运动所形成的角速度以及该角速度垂直于视线的分量,分别得到计算公式,最后通过数值仿真进行验证。结果表明:利用成像导引头提供的失调角信息能够精确解算出该角速度中垂直于视线的分量。     

误差功率谱系数加权法在半捷联制导信息提取中的应用

为了解决半捷联成像导引头视线角速率直接提取噪声大的问题,首先分析了半捷联导引头视线角速率随机噪声的来源,建立半捷联稳定跟踪控制回路的模型,推导出各种误差与输出之间的传递特性。在主要的随机误差源统计分析的基础上,得出主要噪声的功率谱响应,依据功率谱响应对半捷联视线角速率各构成部分进行加权得出加权视线角速率。为了验证加权视线角速率的有效性,在制导回路中进行分析仿真,结果表明:加权方法能够有效抑制导引头测量信息的噪声。以半实物的方式实现半捷联电视导引头,在电视导引头完成双闭环后进行扰动隔离及跟踪靶标,将加权视线角速率提取方法提取制导信息与直接提取方法进行比较,实验结果表明,加权提取方法的视线角速率噪声均方差为0.098 ()/s,比直接合成噪声降低了46%。综上所述,加权方法可以很好地改善半捷联视线角速率噪声大的问题。     

滚-仰式导引头跟踪原理

研究适用于近距格斗空空导弹的滚-仰式导引头跟踪原理。根据导引头探测器上目标的位置信息,导引头稳定平台状态及导引头与弹体间的相对运动关系,导出了导引头跟踪框架角误差信号的数学模型,以实现导引头的闭环控制。然后结合导引头的控制特点,完成了导引头控制系统的设计。结合工程实际应用,研究了导引头跟踪框架角误差简化公式的适用性,研究表明,简化公式和精确公式给控制系统性能带来的主要差别在于由简化公式得到的俯仰通道控制系统较精确公式得到的俯仰通道控制系统稍慢。其造成的影响可以通过俯仰通道与滚转通道带宽比的优化设计来补偿。分析表明,实际应用中可以采用简化公式求导引头跟踪框架角增量,实现导引头的闭环控制。     

导引头跟踪回路滤波特性仿真分析

反辐射导引头是反辐射导弹的重要组成部分,陀螺稳定平台导引头是最常用的一种导引头,给出了制导控制所需的视线角速度信息。但由于平台的随机扰动和被动导引头的测向噪声,导致导引头无法实现视线角速度的准确测量,因此需要对跟踪回路进行滤波,以得到满足制导要求的视线角速度信息。惯性环节滤波器和矩形窗平均值滤波器是2种常用的数字滤波器,通过Simulink仿真对采用这2种滤波器的跟踪回路特性进行了分析,比较了时域和频域的差异性,给出滤波方法的选择依据。     

滚摆导引头视线角速率提取技术

滚转摆动式导引头采用滚转摆动两轴极坐标控制形式,外框为滚动框,内框为摆动框,视场可覆盖整个前半球,具有结构简单、重量轻、体积小、成本低等特点,因此非常适用于近程红外防空导弹。本文讨论了滚摆式导引头与偏仰式导引头视线角速率存在的差异,阐述了滚摆式导引头视线角速度存在x轴分量的原因。并给出了半捷联式滚摆导引头角速率的获取方式,推导了其简化形式,分析了简化公式使用的条件。仿真结果表明,该简化公式具有较好的近似精度,具有一定的工程应用前景。     

半捷联雷达导引头视线角速度提取

在雷达导引头小型化的应用背景下,半捷联雷达导引头省去了稳定平台上的速率陀螺,满足了降低成本和减小体积的要求。与光学导引头相比,雷达导引头还可以获得弹目相对距离,综合距离与角度跟踪信息可以进一步提高信号输出品质。但半捷联雷达导引头无法直接获取用于比例导引的目标视线角速度,本文提出在天线坐标系下建立目标视线微分方程,利用自适应卡尔曼滤波进而结合导弹弹体扰动信息、天线相对运动信息重构视线角速度信号,用于比例制导系统。     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.