基于无源定位的多目标航迹融合技术研究

针对无源定位系统定位误差大、数据更新率不规则等问题,研究了一种通过定位数据辅助信息特征进行多目标航迹融合的新方法。该方法利用信号侦察获取的目标辅助信息作为航迹关联判决准则,并与传统的航迹关联方法相结合,从而实现了对侦察区域内多目标的航迹融合。对该算法的性能分析和仿真验证表明,新算法具有更好的航迹融合性能,更强的通用性和可扩展性;并且在密集多目标环境下可实时、有效地跟踪几十批次的目标。     

基于多维信息的数据处理新技术

常规雷达数据处理技术通常利用回波的距离、方位、多普勒、幅度等信息进行目标跟踪处理,而对于工作在复杂环境下具有低分辨率、低数据率和高虚警特点的雷达,有时候会产生多径航迹和虚假航迹较多等问题.为了提高雷达的跟踪性能,需要综合利用尽可能多的信息进行回波数据的处理.文中设计一种基于多维信息的数据处理新技术,该技术综合利用回波的距离、方位、多普勒、幅度、信噪比、目标航迹等多维信息进行自动跟踪,并利用频谱特征信息进行人工干预.     

一种多元信息辅助的双基地雷达检测跟踪一体化方法

该文针对双基地雷达提出一种多元信息辅助的检测跟踪一体化方法。结合雷达在目标跟踪阶段获取的目标位置与回波幅度等多元先验信息,辅助设计跟踪波门内检测门限,以期提升目标的检测与跟踪性能。该文首先根据已获取的目标位置先验信息,在概率数据互联(PDA)框架下基于贝叶斯最小错误准则修正了传统似然比检测器。为进一步提升弱目标探测性能,该文引入航迹终结准则松弛了门限设置规则,并计算了跟踪波门内的平均虚警概率和检测概率。最后,该文重新推导了多元信息辅助情况下PDA算法的关联概率计算方式,完整地给出了算法流程,并通过仿真实验验证了算法的可行性和有效性。     

基于机器学习支持向量机的海面目标航迹起始算法研究及应用

海面目标跟踪过程受到强海杂波干扰、回波信号时变非平稳、点迹丢失和目标机动等影响,导致传统方法的航迹起始效果较差,出现混批、起始失败和误跟踪等严重后果。针对上述问题,提出了一种基于机器学习支持向量机的海面目标航迹起始算法,采用支持向量机作为分类器,通过样本训练实现对真实目标与虚假目标的分类,将航迹起始问题转化为真假目标的区分和鉴别问题。文中方法利用机器学习的数据驱动策略选择分界面方案代替传统技术中利用先验知识来人工选择门限分界,可以显著减少对先验信息的依赖;同时,门限具有自适应调整的能力,可大大提高算法的自适应性和鲁棒性。最后,利用雷达实测数据对算法的有效性进行了验证。     

跟踪信息辅助的扩展目标检测

雷达带宽增加带来的回波信息增量,能够更准确地辅助环境感知并获取目标信息。但是,雷达带宽的提高通常会造成目标回波在距离维的扩展,进而造成目标回波能量的分散,使单个距离单元的回波信噪比下降,不利于目标的远距离探测。此时,通过融合连续多个距离单元的回波进行检测能够提升目标探测性能。为了更充分地利用目标回波信息设计融合检测器,文中结合认知探测的思想,利用跟踪状态下的目标先验信息设计了跟踪信息辅助的扩展目标检测算法。本算法首先基于扩展目标的跟踪信息预测目标位置及其回波在各距离单元的分布,再基于预测信息设计融合检测器,以此实现从跟踪到检测的闭环,更充分地挖掘和利用了历史目标回波信息。实验表明：所设计的跟踪信息辅助的扩展目标检测算法相较于传统扩展目标检测算法,能够提升目标检测性能,推远雷达对目标的有效跟踪距离。     

基于AIS的对海雷达多目标融合跟踪方法

针对海面密集目标跟踪时数据关联难度大且跟踪精度不高的问题,提出了一种基于船载自动识别系统(AIS)信息的雷达航迹融合方法。首先,根据AIS测量值和雷达的测量噪声等级确定融合系数,保证融合数据的合理性;然后,使用融合后的航迹对雷达测量值作双波门的数据关联处理,优化数据关联方法,提高源于目标测量值的置信度,降低虚警和杂波的影响,进一步提高航迹的稳健性和跟踪精度;最后通过仿真和实测数据证明了所提方法的有效性和优越性。     

基于道路信息的机动小目标跟踪

道路上运动的小目标因密集的交通、大量的虚假点迹以及强烈的机动能力导致其跟踪较难,文中提出了一种利用道路信息改善机动小目标跟踪性能的方法,该方法通过比较道路结构、分叉、交叉等信息和航迹当前所在位置,调整交互多模型的模型数和模型结构,即变结构交互多模型,并通过判断航迹的方向是否与道路的方向一致管理航迹。仿真结果说明与传统的交互多模型相比,结合了道路信息的方法明显提高了机动小目标的跟踪精度,并提高了监测区域内的目标航迹检测概率,同时降低了监测区域内虚假航迹数目和寿命。     

基于幅度辅助的对海雷达航迹起始方法

针对复杂环境下不同雷达观测测量准确度存在差异而导致观测数据质量存在差异的问题,提出了一种基于幅度辅助的对海雷达航迹起始方法。该方法首先利用幅度信息计算幅度似然比,并以幅度似然比的大小来表示观测数据质量的高低,然后将这种幅度信息引起的数据质量差异用于Hough变换参数空间积累后的初选航迹参数的一次修正,提高迭代滤波初值的准确性;然后对一次修正后的初选航迹进行多尺度聚类,利用简单的二次迭代滤波方法分析得到目标的真实航迹起始数目和航迹起始参数;最后通过仿真数据证明了所提方法的有效性和优越性。     

基于雷达测量的多目标联合检测、跟踪与分类方法

利用雷达测量中的目标速度、加速度等属性信息, 基于跳转马尔科夫系统模型高斯混合概率假设密度滤波算法, 提出了一种多目标联合检测、跟踪与分类方法.该方法在进行雷达多目标测量信息处理的多模型混合高斯概率假设密度滤波过程中, 对各高斯项编号, 进行航迹提取, 在滤波处理的同时形成带有航迹编号的明确航迹, 并进行航迹管理; 同时, 根据目标运动模型, 联合利用目标加速度控制输入与速度估计进行多目标分类.仿真试验验证了该方法能够在检测、跟踪的同时, 对目标航迹进行有效类型识别.     

窄带舰船目标识别方法研究

文中针对窄带雷达舰船目标识别问题,提出了一种窄带雷达舰船目标识别方法.该方法从窄带雷达回波信号中提取目标的感兴趣区域,基于感兴趣区域提取目标的期望、标准差、方差、中心矩特征.依据雷达舰船目标航迹信息提取目标姿态角,并将姿态角作为特征引入到分类器中.最后,利用支持向量机方法对窄带雷达舰船目标进行分类.通过建立的仿真数据进...     

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.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

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.     

An improved parallel thinning algorithm with two subiterations

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.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

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.     

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.     

Study of waveguide coupling efficiency in hybrid silicon lasers

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.     

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.     

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.