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1.
TN7 2004040451用遗传算法实现信号转换电路的非线性校正/温秀兰,宋爱国,崔建伟,(2{高桂本(东南大学)11数据采集与处理一2003,18(3)一306一309采用了遗传算法的最新成果,提出了一种新颖的基于实数编码的改进遗传算法用以校正信号转换电路的非线性误差.该算法采用基于代沟最小的  相似文献   

2.
介绍了一种新型、高精度的智能气体体积分数测量设备.该设备将ARM7应用到电路中,利用其强大的数据计算处理能力及控制能力,设计出了显示气体体积分数值的测试电路.传感器输出的电信号采用牛顿插值法进行转换,有效地校正传感器的非线性,提高测量的精度.通过C语言编程实现该算法,经测试,该装置的精度误差保持在±1.5%,能够准确地对环境中的气体进行监控,并具有到限报警功能.  相似文献   

3.
孔俊宝 《电讯技术》1990,30(1):6-16
本文提供一种计算非线性电路的稳态响应的有效算法,在多频信号激励的强迫振荡电路和耦合振荡电路都可使用。该方法可称为“代换算法”。因为,它每一步的变量都是用残留误差的各个频率分量解关联时不变电路,该电路是用“松弛法”将时变电路转换而来。此算法非常简单而有效,并且可应用于各种非线性电路。  相似文献   

4.
提出了一种适合无驱动结构硅微机械陀螺信号线性补偿的新算法,通过补偿理论分析、软件程序编写和调试、硬件电路的构建与实现、实际测试的陀螺仪输出信号和实现补偿后陀螺仪输出信号的对比,论证了该非线性补偿算法的可行性.由实验结果证明了该算法的补偿误差较小,精确性很高;同时可消除由载体自转引起的陀螺信号的误差,从而完善了硅微机械陀螺信号处理系统,使陀螺实用化.  相似文献   

5.
宽带取样示波器Nose-to-Nose校正理论的新进展   总被引:6,自引:3,他引:3  
林茂六  赵华 《电子学报》2001,29(3):409-411
本文根据电路、信号与系统理论并结合实际校测工作对一种适于高速/宽带取样示波器性能校正的新方法——Nose-to-Nose (NTN)法的理论基础作了研究,分析了该方法中的重要信号kick-out脉冲,推导了其数学表达式,提出了"kick-out脉冲与示波器取样系统的阶跃响应成比例"的新观点,最后讨论了NTN方法误差及电路非线性和非对称性对校正的影响.  相似文献   

6.
针对FMCW (Frequency Modulated Continuous Wave) SAR(Synthetic Aperture Radar)调频非线性误差对一维聚焦性能影响和该误差校正问题,该文引入VCO(Voltage Controlled Oscillator)调频非线性高阶误差模型,从理论推导、定量分析了调频非线性误差对信号的具体影响.在VCO工作稳定、随时间电漂移度较小的前提下,提出了一种基于开环的FMCW SAR非线性校正方法.该方法首先一次补偿谐波误差,以信号压缩指标性能最优为收敛准则,通过迭代来校正因输入电压的更新和VCO电漂移及热噪声而引起抖动的高阶误差,进而对信号的调频非线性进行校正.信号仿真和实测数据处理结果表明该方法能对FMCW SAR信号源的调频非线性误差进行稳健、有效的校正,并且与传统的开环软件校正方法相比,该方法无需构建复杂的误差模型,具有简单、经济、运算量较小等优点.  相似文献   

7.
FBG电流互感器非线性校正系统研究   总被引:1,自引:1,他引:0  
为了提高电流互感器的测量精度,减小相位误差 ,研究了基于现场可编程门阵列(FPGA)的光纤光栅(FBG)电流互感器非线性校正系统,分析 了超磁致伸缩材料GMM,giant magnetostrictive material)的 磁滞特性,采用参数可变曲线拟合法实现数据的非线性校正处理。通过FP GA完成数据采集、 滤波、缓存、分频、校正处理和数据转换等单元的设计,实现了对电流互感器输出信号的实 时非线性校正,减小了GMM的磁滞特性对FBG电流互感器的影响,使电流互感器的 相位误差由7°降为1°,幅度误差小于1%,提高了电流测试系统的测量精度。  相似文献   

8.
针对全帧转移大面阵电荷耦合器件(CCD)多帧图像数据随时间漂移的现象和测试电路引入的噪声,导致无法准确评估CCD器件的参数,文章提出一种基于行过扫数据校正算法。行有效像元数据与对应行垂直过扫数据同时输出,通过有效像元数据减去垂直过扫数据均值,对图像数据漂移的现象进行抑制。测试电路中模拟模块与数字模块同时作用于单行有效像元数据与垂直过扫数据,通过有效像元数据减去垂直过扫数据均值,消除测试电路引入的噪声。实验结果表明,经过该算法校正后的器件读出噪声减小了20%,暗场差值图像中超过15 e-和25 e-的比例减小了25%。该算法适用于大面阵CCD器件,可校正测试系统引入的测试误差,提高全帧转移大面阵CCD器件测试效率。  相似文献   

9.
基于伪随机序列自相关性的新型超声波测距系统   总被引:2,自引:0,他引:2  
针对传统超声波传感器存在受环境因素影响大、抗干扰能力差等缺陷,提出了一种新型超声波测距系统的设计方法.该超声波测距系统基于伪随机序列自相关性原理,采用模块化设计,可准确地测量出超声波的传播速度和渡越时间,进而计算出障碍物的距离.采用低功耗,高性能的TMS320VC5509A DSP作为信息处理器,采用基于快速傅里叶变换(FFT)的相关判别算法,有效地提高了实时性.改进了超声波接收电路,采用高速绝对值电路代替传统的检波电路,可高效地从接收到的超声波信号中解调出伪随机序列.根据所设计的超声波测距系统的工作原理,提出了适用于该系统的误差校正方法.在干扰存在的情况下,进行了性能测试实验,实验结果表明,该超声波测距系统的测距误差在1.8%以内,具有良好的抗干扰性.  相似文献   

10.
周维  陈默  王赤  张秋菊 《信息技术》2004,28(7):105-108
介绍了一种数字型PID嵌入式温控式系统。该系统由PC104、传感电路、变送器电路、可控硅控制电路及PID软件功能包和非线性校正软件功能包组成,具有实时监控和自动调整温度等功能。重点介绍了系统的软件设计部分,即用软件实现了PID算法及传感器的非线性校正的方法,系统采用可视化编程语言VB进行编程。  相似文献   

11.
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.  相似文献   

12.
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…  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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   

20.
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.  相似文献   

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