一种改进的非线性外推图像增强算法及在高分辨率图像重建中的应用

对非线性外推图像增强算法进行分析，充分考虑图像高频分量的局部特征，提出一种新的非线性滤波剪切策略包络阈值剪切算法，改进后的算法使整幅图像的增强趋于均匀化，增强效果显著改善，结合该算法重建得到的高分辨率图像，明显优于只用插值算法得到的结果。     

小波分析包络提取及在DSP上的实现

在实时信号分析中，离散小波变换在DSP上的有效应用受到了特别的关注，介绍了Mallat快速小波变换算法，通过与常用小波基相对应的正交镜像滤波器组，实现了对信号的快速小波分解；利用小波的频带分离特性和噪声的小波变换特性，提高了信号包络提取的精度。     

恒包络预编码算法研究

主要介绍了在大规模MIMO系统中的恒包络预编码算法,描述了该算法提出的背景,介绍了恒包络预编码向量的求解方法.然后重点分析了在非完美信道状态信息条件下的恒包络预编码算法,计算了非完美CSI对恒包络算法的影响,分析表明,该误差所带来的影响与恒包络预编码向量无关,而只与信道估计误差有关,从而可以通过选择合适的估计算法和导频序列,来减少估计误差带来的影响.     

恒包络预编码算法研究

主要介绍了在大规模MIMO系统中的恒包络预编码算法,描述了该算法提出的背景,介绍了恒包络预编码向量的求解方法。然后重点分析了在非完美信道状态信息条件下的恒包络预编码算法,计算了非完美CSI对恒包络算法的影响,分析表明,该误差所带来的影响与恒包络预编码向量无关,而只与信道估计误差有关,从而可以通过选择合适的估计算法和导频序列,来减少估计误差带来的影响。     

用改进的包络最小熵法进行包络对齐

包络对齐是逆合成孔径雷达(ISAR)运动补偿的基础。现有的包络对齐算法存在对齐精度较低的缺点。本文借助 Fourier变换的频域移位性质,改进了包络对齐处理的包络最小熵法。该算法在用包络最小熵法进行平动位移粗略估 计的基础上,利用频移因子对粗补偿的距离像进行小范围的调整和迭代,以获得更高的包络对齐精度。给出了详细 的算法流程和步骤。仿真数据和外场实测数据的处理结果都表明该方法的有效性。     

基于子孔径包络误差校正的SAR高精度运动补偿方法

目前,SAR正在向体积小、重量轻、功耗低的方向发展,由于受气流的影响,微小型SAR平台极易偏离理想航迹,大幅运动误差造成SAR图像质量严重下降,因此在微小型SAR成像处理过程中对运动误差的精确补偿十分重要。运动误差会造成包络误差和相位误差,传统运动补偿算法往往忽略包络误差的空变性,但是当运动误差幅度过大时空变的包络误差会对成像质量造成严重影响。该文提出与频分子孔径运动补偿算法相结合的包络误差校正方法,该方法消除了空变包络误差的影响,从而改善了成像质量。仿真和实测数据处理结果验证了该算法的有效性。      

基于小波包和ZFFT的舰船辐射噪声调制特征融合和提取

舰船噪声调制包络谱是水下目标识别的重要特征。本文提出了一种基于小波包分析和ZFFT的高频噪声解调分析(DEMON)方法,对多子带包络谱进行融合,得到了线谱特征明显的DEMON谱;利用倍频算法,对DEMON谱进行了轴频提取。舰船实测数据证明该分析方法的可行性和有效性。     

基于FPGA伪码快速捕获的优化设计

为了在扩频通信中实现伪码的快速捕荻,通过对相关积分包络算法的改进,对接收信号未知伪码进行相位搜索,完成了FPGA仿真验证,实现的伪码捕获具有结果误差小、捕获时间短、占用资源少等特点。     

激光测量系统不确定度最小包络椭球模型研究

为了对激光测量系统的测量误差3维空间分布进行有效评估,以特定点测量或仿真的大量位置数据为基础,采用孤立森林算法对点云进行了异常数据筛除.基于误差椭球理论,引入粒子群优化算法,针对有效数据建立了最小包络椭球的不确定度模型;采用测量场与单点不确定度的坐标系变换,将不确定度最小包络椭球模型应用于测量场景内不确定度场的空间分布...     

基于Internet的DEA效率评价软件

本文介绍了数据包络分析方法的基本思想以及CCR基本模型,构造了CCR模型的算法流程.编写了一个可以通过Web Server浏览操作的DEA效率评价软件,文中给出软件结构框架,最后给出实例分析.     

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.