一种激光三角测量的标定方法及误差分析

为了解决激光三角测量法在标定时,不能直接准确地测量激光器端口与标定物的距离的问题,采用了一种基于距离差进行标定的方法。该方法利用标定物移动的距离作为标定输入,改进了测量系统的标定方法;采用高斯-牛顿迭代法计算测量系统的参量,分析了测量系统在标定时可能产生的激光像点提取误差和非垂直误差。结果表明,测量距离的精度可达到4.000mm。该方法能够准确标定激光三角测量系统的参量。     

Colliding pulse phase detector for picosecond resolution timing measurement

A phase detector consisting of Schottky diode peak detector taps distributed along an integrated GaAs transmission line has been fabricated. Pulses counterpropagate on the line, forward biasing taps in the region of pulse overlap. The relative phase gain, determined from the captured overlap function, is 20 mV/ps.<>     

天空光辐射亮度测量系统定标及数据分析

随着辐射测量技术的不断发展,测量设备的精度越来越被关注,而对设备准确定标是提高测量设备精度的重要保证.详细介绍了利用标准光谱辐射计实现天空光辐射亮度测量系统的实验室绝对辐射定标方法和利用汞灯实现天空光辐射亮度测量系统的波长定标方法,并采用前述方法对TKFS01型天空光辐射亮度测量系统进行了定标,给出了定标的不确定度.通...     

High-frequency periodic time-domain waveform measurement system

A system is presented for the accurate measurement of high-frequency periodic time-domain voltage and current waveforms of a nonlinear microwave device. The measurements are performed in the time domain using a high-speed sampling oscilloscope. The results are Fourier-transformed into the frequency domain for error correction and then back into the time domain. An error-correction algorithm is presented that makes it possible to obtain accurate waveforms in spite of nonideal system components. Practical difficulties in measurement-system characterization are also discussed. An accurate circuit model for the measurement fixture is developed and its element values are determined. Measurement results are given showing the waveforms in a microwave transistor operated in the nonlinear region. The errors caused by signal processing are discussed     

Calibration and measurement of a wideband six-port polarimetricmeasurement system

The principle of operation, calibration procedure, and experimental results of a wideband six-port polarimetric measurement system are described in this paper. This measurement system can measure the polarization states of incoming waves and the polarimetric scattering matrices of scattering targets from the wideband power data. The imbalances and coupling between antenna polarization channels and the characteristics of microwave components used in the measurement system are calibrated using three partly unknown scattering calibrators that are illuminated by four unknown-polarized calibrating waves     

用半导体激光器实现50KV脉冲波形安全测量方法的研究

一种可确保人身和设备安全的高压脉冲波形的测量方法。它由发送电路将被测电压或电流之实时值转换成串行数字信号，再用它调制半导体激光器发出的光，其湛我穿过100mm以上变压器油和10mm厚玻璃板，送给接收电路。后者将串行数字信号转换成模拟信号，然后送给示波器，即可观察到被测高压脉冲电路电压或电流的波形。所述方法新颖实用，具有参考价值。     

车载移动立体测量系统检校及精度分析

车载移动立体测量系统可以用于快速、准确的高精度数据采集和三维建模。针对车载移动立体测量检校问题,设计了一套高精度的车载移动立体测量系统检校方法,建立了检校的数学模型,并进行了试验,分析了检校前后车载移动立体测量系统的测量精度差异。实验证明,本文研究的车载移动立体测量系统检校方法能有效地提高系统测量精度。     

基于光子晶体光纤放大系统的皮秒方波产生

在光子晶体光纤飞秒激光放大系统中,利用液晶空间光调制器的调制特性,实现了对超短激光脉冲实时、可控的脉冲振幅整形,分析了大线性啁啾方波脉冲在放大过程中的频域和时域形状随泵浦功率的变化规律,在此基础上,通过液晶空间光调制器对主放大器前的脉冲频谱形状进行了预先调整,放大后获得了中心波长为1 031 nm,光谱宽度为13 nm,脉宽为15 ps的方波脉冲,证实了采用光谱优化后的飞秒脉冲作种子,可以较好地克服光子晶体光纤放大器增益不均引起的频谱形状的变化。     

20 GHz on-chip measurement of ESD waveform for system level analysis

Reliability of embedded electronic products is a challenging issue regarding ElectroStatic Discharge (ESD) events into real live applications. This is strongly related to the increased number of embedded systems and to technologies shrinking that result in less robust chips. To ensure the safety of electronic systems, the ESD events have to be taken into account at first design phase. But equipment manufacturers are facing the dilemma that no information is provided by the semiconductor manufacturers. At the same time Integrated Circuit (IC) designers have to take into account the final application environment to build the ESD protection strategy. Depending on the external components (external means around the chip) the on-chip current path could change. Understanding how the system environment impacts the current path within the chip is needed. This paper deals with on-chip oscilloscope developed for in-situ measurement of real ESD event in 65 nm CMOS technology. The measurement bandwidth of the embedded sampler is 100 GHz, and 20 GHz for the probes. Thanks to this technique, impact of the system on the current path of the on-chip ESD strategy will be observed. Some measurement results during an ESD stress on an I/O structure will be presented and analyzed showing that PCB trace and package induce the creation of new current paths.     

椭圆球面波脉冲产生系统量化误差分析

椭圆球面波函数（PSWF）特性优良,是极具前途的非 正弦函数。由于幅度量化及数模转换器（DAC）输入位数有限,在基于直接数字波形合成的P SWF脉冲产生系 统中,量化误差不可避免。给出该产生系统误差模型,重点针对量化误差问题,从随机信号 分析的角度分析了PSWF脉冲产生系统中影响幅度量化误差大小的主要因素,通过仿真定量分 析了量化误差对所产生PSWF脉冲时域波形、频谱及互相关特性和频域能量聚集性等重要特性 的影响。理论分析和仿真结果表明：产生系统采用高于4倍的过采样率和大于12 bit的量化 即可有效降低量化误差对产生PSWF信号性能的影响。所得结论对工程应用研究具有一定参考 价值。     

All-electronic free-space picosecond pulse generation and detection

An all-electronic system for generating, propagating and detecting picosecond electromagnetic pulses using monolithic integrated circuits is described. With a 1.8 ps (10%-90%) nonlinear transmission line step generator driving a monopole antenna for transmission and a similar antenna driving a diode sampler for reception, the system has shown spectral coverage from 90 to 170 GHz.<>     

Improved Raman-fibre pulse delay measurement system

An improved design for pulse delay measurements using a Raman generating fibre pumped by a Nd:YAG laser has been realised. The reproducibility error in the measured delay times is only 2 ps RMS, because of strongly reduced jitter, compensation of long-term instability and prevention of irregularities in the shape of the pulses.     

基于误差椭球的激光测量系统的不确定度分析

为了对3维激光扫描技术的测量精度做出评估,以激光雷达测量系统为研究对象,基于误差椭球理论建立了测量系统的点位误差模型;依据点云平面误差椭球的分布特性,提出了点云拟合平面的不确定度模型,用于评估与拟合平面关联的尺寸测量精度;通过对箱体类物体高度的测量实验,获得了实际测量不确定度,并与模型仿真结果进行了对比。结果表明,该模型可较准确地估算出高度的测量不确定度,从而验证了其有效性及实际意义。     

基于小波分析的不对称脉冲信号波形研究

不对称脉冲轨道电路设备产生的不对称脉冲信号,在传输中由于轨道分路不良和干扰等出现失真,这就需要研究一种更为准确、可靠和抗干扰性能好的检测方法来完成对信号的实时分析与检测。基于小波分析的不对称脉冲信号波形检测,利用小波变换模极大值特性,可以有效地解决这个问题。结果表明,该方法有较强的适用性,算法简单,运算速度快。     

Analysis of picosecond pulse shape synthesis by spectral masking in a grating pulse compressor

This paper analyzes the synthesis of arbitrarily shaped optical pulses by spectral filtering in a fiber-and-grating pulse compressor. Spectral filtering of phase and amplitude is achieved by masking the spatially dispersed frequency components within the compressor. We show that the spectral filter is the convolution of the mask with the beam's transverse intensity profile. We discuss the effect of diffraction from the features of the physical mask, and show how finite spatial resolution limits the range of attainable temporal profiles. The fundamental limitation on spectral resolution is derived. Spectra and temporal pulse shapes corresponding to a variety of physical masks are calculated and are found to be in excellent agreement with experiments done with compressed pulses from a mode-locked Nd: YAG laser.     

电子测量误差分析研究

人们的生活会受到电子测量的结果影响,由于测量的过程难免受到多种因素的干扰,电子测量的结果会存在误差,本文从电子测量误差的概念出发,分析了造成测量误差的原因,并提出了消除电子测量误差的方法。     

Electrostrictive self-focusing of picosecond laser pulse trains

A nanosecond-long train of picosecond laser pulses theoretically can produce self-focusing by electrostriction, even though the trapping threshold for a single picosecond pulse is very high. The relative roles of electrostriction and various types of Kerr effect in picosecond pulse train self-focusing should be assessed.     

Error-corrected large-signal waveform measurement system combiningnetwork analyzer and sampling oscilloscope capabilities

A large-signal automatic stepped CW waveform measurement system for nonlinear device characterization is presented that combines the high accuracy of a vector network analyzer with the waveform measurement capabilities of a sampling oscilloscope. A large-signal error model and a corresponding coaxial calibration procedure are proposed to describe the systematic errors of the measurement setup. The error parameters and the correction algorithm are independent of the properties of the RF generator. System accuracy is investigated by Schottky diode verification measurements with different offsets from the reference plane. GaAs MESFET reflection and transmission response measurements with error correction extended to the planar device under test (DUT) reference planes are given     

模拟内插法及其测量误差分析

时间间隔测量技术在众多领域已经获得了应用,如何提高其测量精度是-个迫切需要解决的问题.本文在分析电子计数法测量原理与误差的基础上,重点介绍了模拟内插方法,并且对其测量误差进行了分析,提出了相应解决办法.     

低频/甚低频电磁脉冲测量系统研究

为了准确地测量电磁脉冲（electromagnetic pulse,EMP）的波形,开展低频/甚低频（low-frequency/very low-frequency,LF/VLF）EMP的形成和传播机理研究,识别不同EMP的特征,并以此为依据来识别、确认雷电及核爆炸等现象,提出了一种高分辨率的EMP原始波形测量系统方案,同时针对LF/VLF这一较低的频段提出了一套有效的系统标校方法,实现了对EMP的连续、准确测量和快速有效判别,并能通过网络实时上传数据.系统采用正交环磁场天线和平板电容电场天线实现信号的接收,设计了低噪声高保真的信道调理电路和高速数据采集电路来实现信号的采集,利用高精度的授时模块为EMP信号标记时间戳,最后结合多点监测波形实现EMP定位估计.实测结果表明:该系统能够给出高分辨率、高精度的LF/VLF EMP波形;利用该系统组网可以实现远距离EMP源的定位,定位精度与目前近距离的定位手段相当.通过长期的运行,验证了该系统具有高可靠、低失真、判别准确、实时性强等特点.