一种基于DSP的弱小目标实时检测算法研究

针对天文CCD图像的特点,讨论了天文图像处理中小目标检测算法,采用DSP FPGA的硬件架构来实现低信噪比情况下小目标的实时检测与跟踪。针对系统不同的工作状态提出了在引导状态下使用基于图像对称差分运算的方法来检测跟踪目标,而在定位状态下使用基于形态学滤波的检测方法实现多目标的检测,同时保存感兴趣的目标图像,实验的结果表明可以实时有效地检测到SNR≈2的运动小目标。     

一种天文光电图像序列弱小目标实时检测算法

地基大视场天文光电观测系统获取的序列图像中,空间目标和数目众多的恒星目标成像特性相似,大部分都表现为弱、小目标特性,实现它们稳健实时检测具有较大的难度.本文在深入分析天文光电图像弱小目标成像特点的基础上,结合实际工程对目标检测的强实时性和高检测概率需求,针对恒星目标和空间目标的时空域特性差异,提出了一种基于时空域联合滤波的弱小目标枪测算法,首先在空域上通过抑制背景增强目标,然后在时域上分别通过多帧相关运算和多帧差分运算,快速有效地检测恒星目标和空间目标.最后结合实测数据和硬件平台,验证了该方法的有效性及实时性.     

基于USB的天文图像获取及实时处理系统设计

针对某空间目标监视系统的实时目标检测需求,结合所采用CCD相机的接口形式,本文设计并实现了一套基于USB 2.0的高分辨天文图像获取及实时处理系统。首先在深入分析USB 2.0协议的基础上实现了相机数据获取接口,其次结合弱小目标检测算法流程,提出并实现了一种基于DSP＋FPGA的可重构实时信息处理机的硬件实现方案。测试结果表明该设计能实现对复杂环境下低信杂比、低对比度的弱小目标的有效检测,并满足探测系统实时性的要求。     

红外序列图像中小目标实时检测系统设计与实现

针对天空背景下红外序列图像中小目标检测实时性以及工程化的要求,设计了一种基于FPGA+双DSP的实时检测系统,用硬件方式实现了红外图像高通滤波、自适应阈值分割、管道滤波的组合检测算法.通过对实测红外序列图像进行实验表明,该系统能实时、有效的检测25帧/s的低信噪比红外序列图像.     

利用自适应模糊推理PMHT算法的红外小目标跟踪与检测

提出了一种基于自适应模糊推理PMHT算法对红外序列图像的小目标进行跟踪和检测.对红外序列图像进行中值滤波、边缘提取、海天线识别与对消等预处理后,可以提取出若干个备选小目标,通过PMHT与模糊自适应相结合算法来实现对备选目标的跟踪和数据关联,最后,根据先验知识和检测条件实现小目标检测.算法通过模糊自适应来调整系统噪声方差,经过多次迭代,从而实现数据关联以及目标模型实时检测.另外,在多目标跟踪中存在目标重叠的现象,运用"记忆和填充"方法来解决多目标的合并和分裂问题,算法易于硬件实现.通过对实际的红外序列图像进行小目标检测,验证了所提方法的可行性和有效性.     

天文光电观测系统实时信息处理机的设计与实现

针对地基天文光电观测系统获取图像数据量大、实时处理难度高等特点,设计并实现了以高可靠CPCI工控机为平台、基于FPGA+双DSP TMS320C6455的实时信息处理机。详细介绍了实时信息处理机硬件结构,深入分析了实时信息处理机的设计特点。针对实时信息处理机实时图像获取和实时图像处理的主要任务,重点描述了工程实现过程中图像获取及处理流程、弱小目标检测算法实现、DSP任务分割和速度优化等。外场实验及大量实测数据处理结果验证了该处理机的实时性和处理能力,满足了天文光电观测系统的要求,为高分辨率图像的处理运算提供了可靠的硬件平台。     

红外小目标实时检测系统实现

采用TI的C6416为核心处理器,辅以FPGA,构建了一套红外小目标实时检测系统,主要算法由两片C6416并行处理实现,FPGA完成图像预处理和对外接口.算法上提出了基于双滑窗的局部阈值二值化方法,并采用图像预处理技术来改善图像分割效果,利用目标在连续帧间运动的关联性来剔除干扰目标、降低虚警概率.实验表明,系统的目标检测效果和实时性均达到了要求.     

一种红外大视场环境下的多小目标实时检测方法

为了实现大视场条件下的多小目标实时检测,提出并实现了一种对原始图像先在“粗”尺度下做小目标存在区域的估计和分割,再在这些区域内做多小目标对象的检测和处理的“由粗到精”的红外小目标两阶段分块检测方法,实践证明了本算法的有效性.     

一种红外小目标的图像检测方法

针对复杂背景条件下的红外图像目标检测问题,将空域滤波和时域滤波相结合,提出了基于数学形态学的目标检测算法.该算法先对原始图像序列作能量膨胀累积以增强目标信息和提高信噪比,然后采用基于数学形态学的Top-Hat变换空域滤波处理技术消除在目标尺度范围外的背景、干扰和噪声,达到探测目标的目的.仿真结果验证了该算法是一种实时、有效,且易于实现的目标探测方法.     

基于FPGA的“低慢小”目标检测系统实现

为解决“低慢小”目标检测困难的问题,实现了一种基于FPGA(Field Programmable Gate Array,现场可编程逻辑门阵列)的“低慢小”目标检测系统。该系统采取COMS相机获取图像,DDR3 SDRAM缓存视频帧,使用FPGA处理帧间差分法和光流法结合的算法,目标检测结果使用VGA标准显示。测试结果表明,该系统能够检测出在悬停和低速飞行姿态下的低慢小无人机目标并实时显示。     

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.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.