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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.
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   

9.
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   

10.
为改善包络跟踪(ET)发射机带宽、效率、线性度等指标,需优化其关键电路性能并校正系统非线性行为。针对该问题,该文构建电源调制器等效模型,推导其效率极值并阐述效率优化方法;引入频率补偿网络来提升电路带宽及线性性能;基于系统非线性行为特征,提出包络增强型数字预失真模型及线性化方案;设计实际电路并搭建包络跟踪系统。对于S频段5/10/20 MHz带宽6.7 dB峰均比测试信号,该系统功放平均效率分别为61%, 54%, 44%,且矢量幅度误差(EVM)均优于1%,具有较好的带宽、效率、线性度等性能,验证了电路优化方法及非线性行为校正方案的可行性。  相似文献   

11.
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   

12.
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.  相似文献   

13.
This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.  相似文献   

14.
An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.  相似文献   

15.
The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO>6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.  相似文献   

16.
This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.  相似文献   

17.
We have fabricated the white organic light-emitting devices (WOLEDs) based on 4,4' -bis(2,2 -diphenyl vinyl)-1,1' - biphenyl (DPVBi) and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene (rubrene). The device structure is ITO/2T-NATA (20 nm)/NPBX (20 nm)/CBP: x%Ir(ppy)3:0.5% rubrene (8 nm)/NPBX (5 nm)/DPVBi (30 nm)/Alq(30 nm)/LiF(0.5 nm)/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris (2-phenylpyridine) iridium [Ir(ppy)3], acts as a yellow light-emitting layer, and N,N' -bis- (1-naphthyl)- N,N' -diphenyl -1, 1' -biphenyl-4,4' -diamine (NPBX) acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir (PPY)3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.  相似文献   

18.
To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.  相似文献   

19.
本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。  相似文献   

20.
We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.  相似文献   

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