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探讨了一种新的低仰角跟踪技术,这一技术的关键是采用俯仰偏焦双波束.天线视线指向目标和目标像的中点时,根据基于两接收天线输出电压的相位差可计算出目标的高度或仰角.本文给出了误差分析和计算机仿真结果,并同其它类似的技术进行了比较.仿真结果表明:这一技术是有效的,并对反射系数在K=0.6~1之间有较好的适应性. 相似文献
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本文介绍了空对空跟踪情况下估计强机动飞机目标运动的一种新方案。研制了一种相互作用滤波器系统,该系统根据目标视线角数据,通过调节运动状态滤波器的估值,提供改善了的目标运动状态估值。设想以与光电跟踪器一起使用的图形识别技术来提供目标的方向信息。目标定向滤波器通过用当前目标运动的最佳估值对测得的视线角进行统计加权来处理视线角的观测值。应用空气动力学升力方程来建立近似攻击角与目标速度和加速度的关系,也研究了飞机目标法向加速度的新颖统计模型,以便更好地表示未知目标的加速度。为评价相互作用滤波器系统的性能,还提供了真实三维情况的仿真结果。 相似文献
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以半捷联寻的制导武器为对象,研究了捷联末制导系统中的捷联控制算法和制导信息滤波模型。首先分析了捷联末制导系统的工作原理,给出了捷联天线稳定平台的跟踪控制算法,然后针对捷联控制算法对目标视线角信息的需求,考虑仅有角度测量的被动制导情况,提出了一种基于M arkov随机模型的机动目标跟踪模型,通过推广Kalm an滤波技术可以获得目标视线角的估计。因为捷联末制导系统无法直接测量目标视线角速度,为了满足弹上比例导引的需要,提出了一个末制导系统角跟踪通道的数学模型,该模型可以采用常规的Kalm an滤波算法获得目标视线角速度的估计值。最后,通过一系列数学仿真验证了上述方法的有效性。 相似文献
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在现代战术导弹末制导系统中,捷联稳定方案在成本、体积方面与传统的陀螺稳定方案相比具有明显优势,是战术导弹导引头的发展方向,其技术核心是数学稳定平台和捷联稳定算法.研究了半捷联末制导系统中数字稳定平台的控制算法和制导信息提取方法,给出了一套适于工程实现的数字稳定控制算法和相应的目标视线角速度信息获取算法.首先探讨了捷联稳定控制原理,然后提出了一种数字稳定平台的实现算法和目标视线角及视线角速度等制导信息的解算方法,为了克服传感器精度和微分运算不理想所造成的视线角速度计算精度不足,又给出了一种基于导弹-目标角跟踪模型的目标视线角速度滤波模型,最后通过数学仿真验证了上述方法的有效性. 相似文献
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基于雷达和成像传感器的融合跟踪 总被引:13,自引:0,他引:13
基于战术防空导弹的跟踪制导问题提出了一种利用雷达和成像传感器的融合跟踪方法。成像传感器获得的目标姿态观测,对目标机动十分敏感,而成像传感器得到和目标视线角观测十分精确,不存在角闪烁现象,数据融合技术充分利用了雷达和成顺的观测信息,显著地改善了机动目标的跟踪性能,大大减小了目标机动引起的脱靶量。 相似文献
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导引头随动系统中信号处理延迟的影响及其补偿算法 总被引:1,自引:0,他引:1
新体制导引头的信号处理方式越来越复杂,造成了非常明显的信号处理延迟,这种纯延迟环节又严重影响着导引头随动系统的跟踪能力.首先采用相位裕度的概念定量分析了延迟大小对随动系统带宽的影响,然后针对目标、导弹、导引头空间运动关系的特点,介绍了一种基于机动目标"当前"统计模型和自适应Kalman预测滤波的探测器信号处理延迟补偿方案,采用探测器输出的跟踪误差和电位器输出的角度信息重构视线运动量测值,利用Kalman滤波获得当前时刻视线角位置的最优估计,进而得到当前时刻跟踪误差的预测值,取代被延迟的跟踪误差进行随动系统的闭环控制,仿真表明本方案有效可行. 相似文献
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Michael Reilly 《半导体技术》2004,29(12)
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. 相似文献
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Thomas M.Trexler 《半导体技术》2004,29(5)
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. 相似文献
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The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation. 相似文献
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The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high. 相似文献
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Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible. 相似文献
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Qi-jiang Ran Pei-de Han Yu-jun Quan Li-peng Gao Fan-ping Zeng Chun-hua Zhao 《光电子快报》2008,4(4):239-242
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's. 相似文献
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Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it. 相似文献
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It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output(MIMO) communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory. 相似文献
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A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working. 相似文献
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《中国通信》2014,(7)
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks 相似文献