取样示波器nose-to-nose校准技术中kick-out脉冲的研究

研究了nose-to-nose校准技术中关键信号kick-out脉冲产生的机理以及影响因素,并通过将两台Agilent86100系列的50GHz的取样示波器对接,获得了kick-out脉冲的响应波形.     

基于"NTN"技术的宽带取样示波器的校准

介绍了用于校准宽带取样示波器的详尽模型法和脉冲标准法 ,并指出了它们的缺陷。着重介绍了可以进行自校准的“NTN”技术 ,该技术的基本设计是将三台取样示波器以“NTN”形式两两对接 ,其中一台对直流进行采样 ,用反卷积分离另一台取样示波器的响应波形 ,并通过解方程组可得到示波器的冲激响应。最后给出了用反卷积分离取样示波器冲激响应的计算机仿真。     

基于NTN技术的宽带取样示波器带宽不确定度的研究

NTN技术是一种校准宽带取样示波器的新方法,其提供的测量量是kick-out脉冲响应(显示)波形数据,而宽带取样示波器的带宽是对kick-out脉冲响应波形数据进行反卷积分离等处理获得的导出量.提出了一种基于NTN技术的宽带取样示波器带宽不确定度的评定方法.首先分析了NTN技术引入不确定度的主要因素;然后提出了由测量量导出带宽的不确定度的传递算法流程,并推导了线性内插的不确定度传递算法;最后给出了宽带取样示波器带宽不确定度的评定结果.     

基于NTN技术的宽带取样示波器自动校准系统

与其它宽带取样示波器校准技术相比,NTN校准技术能够精确地获得取样示波器的冲激响应和复传递函数。但是,由于NTN校准技术要求两台取样示波器的输入端直接对接,这样就很难通过前面板对取样示波器进行操作。为此,介绍了一种基于NTN校准技术的宽带取样示波器自动校准系统,并详细介绍了系统的组成、功能及校准结果。该系统的整个校准工作是在PC机控制下完成的。     

基于NTN校准技术的脉冲标准法

脉冲标准法是校准宽带取样示波器的一种行之有效的方法,但它需要波形参数已知的脉冲信号源,当取样示波器的带宽很宽时,这种脉冲信号源是很难得到的。近年来发展起来的NTN校准技术可以不受带宽的限制,但是它只限于对某些结构的取样示波器的校准。提出了一种基于NTN校准技术的脉冲标准法,该法克服了上述限制,可以实现更多种类的宽带取样示波器的校准。实验结果表明,该方法是非常有效的。     

基于NTN技术的宽带取样示波器过渡时间不确定度的研究

NTN技术是一种校准宽带取样示波器的新方法，NTN技术提供的测量量是kick—out脉冲响应（显示）波形数据，而宽带取样示波器的过渡时间是对kick—out脉冲响应波形数据进行反卷积分离等处理才能获得的导出量。提出了一种基于NTN技术的宽带取样示波器过渡时间的不确定度的全面评定方法。首先分析了NTN技术引入不确定度的主要因素，给出了不确定度计算公式；然后结合数据处理过程推导出不确定度的传递算法；最后给出了宽带取样示波器过渡时间不确定度的评定结果。     

Nose-to-Nose校准技术的仿真研究

Nose-to-nose校准技术可以对任意带宽的取样示波器进行自校准．早期的研究工作集中在对关键信号hick-out脉冲的仿真．本文从不同的角度对微波二极管取样头电路进行了全面的仿真,得到了结论：hick-out脉冲是由于在取样电路的不平衡时选通脉冲的泄漏造成的．并对NTN校准技术从仿真实验到物理实验做了介绍．     

86100A/B(DCA)宽带取样示波器原理、用途及校准方法

86100A/B取样示波器是一种宽频带、多功能的电子测量仪器.本文简叙了该仪器特有的功能、测量原理以及校准方法.由于高达50GHz的频带宽度,用经典的标准脉冲法已无法进行校准(即无法量值溯源),文中介绍了用NTN校准技术的新方法,进行50GHz取样示波器的上升时间、频带宽度的测量.     

86100A/B(DCA)宽带取样示波器原理、用途及校准方法

86100A/B取样示波器是一种宽频带、多功能的电子测量仪器。本文简叙了该仪器特有的功能、测量原理以及校准方法。由于高达50GHz的频带宽度,用经典的标准脉冲法已无法进行校准(即无法量值溯源),文中介绍了用NTN校准技术的新方法,进行50GHz取样示波器的上升时间、频带宽度的测量。     

基于光脉冲源的脉冲标准法中的时基漂移去除

时基漂移是影响取样示波器在时域精密测量高速脉冲信号的关键因素,所以要尽可能设法去除。本文研究以示波器86100C取样模块86118为设备背景,首次利用互相关算法对实时采集的数据,进行了去除时基漂移的研究,并用反卷积技术实现了示波器的校准。研究结果表明,互相关算法去除时基漂移效果明显、优于其他算法,并在一定程度上提高了光脉冲法校准示波器的校准准确度。     

A fast-pulse oscilloscope calibration system

A system is described for calibrating high-bandwidth oscilloscopes using pulse signals. The fast-pulse oscilloscope calibration system (FPOCS) is to be used to determine the step response parameters for digitizing oscilloscopes having bandwidths of ~20 GHz. The system can provide measurement traceability to standards maintained at the U.S. National Institute of Standards and Technology (NIST). It comprises fast electrical step generation hardware, a personal computer (PC) and software, and a reference waveform, i.e., a data file containing an estimate of the step generator output signal. The reference waveform is produced by prior measurement by NIST of the step generator output signal (calibration step signal). When the FPOCS is in use, the calibration step signal is applied to the device under test, which is an oscilloscope sampling channel. The measured step waveform is corrected for timebase errors, then the reference waveform is deconvolved from it. The results are impulse, step, and frequency response estimates, and their associated parameters (e.g., transition duration, transition amplitude, -3 dB bandwidth) and uncertainties. The system and its components are described, and preliminary test results are presented     

On the model building for transmission line cables: a Bayesian approach

This work is aimed at building models to predict the bending vibrations of stranded cables used in high-voltage transmission lines. The present approach encompasses model calibration, validation and selection based on a statistical framework. Model calibration is tackled using a Bayesian framework and the Delayed Rejection Adaptive Metropolis (DRAM) sampling algorithm is employed to explore the posterior probability of the unknown model parameters. Two model classes are proposed to predict the bending vibrations of a typical high-voltage stranded cable. Both model classes account for the aerodynamic damping with the surrounding medium and the bending stiffness of the cable. The difference between the two relies on the damping model chosen to quantify the energy dissipation due to friction among the constituent wires of the cable. Model ranking is rigorously quantified by means of a Bayesian model class selection approach, in which both the data-fitting capability and complexity of each model class are simultaneously taken into account. Experimental tests are performed on a laboratory span with a typical high-voltage stranded cable. The measured frequency response functions are the observable quantities employed in the Bayesian model updating for the two model classes proposed. Both model classes provide comparable and accurate predictions for the cable’s frequency response functions within the range [5, 25] Hz, with the fractional derivative-based model class providing the most accurate predictions. Nonetheless, both model classes failed to accurately reproduce the measured cable’s dynamic response within the frequency range [25, 30] Hz.     

Performance function for time-jittered equispaced samplingwattmeters

This paper evaluates the effect of time-jitter in the equally spaced sampling wattmeters on the hypothesis of equal effects in the two channels and a jitter uncorrelated with the input signals. It is shown that time-jitter, which is a random fluctuation with respect to the nominal sampling time, introduces a frequency limitation which is evaluated together with that due to the sampling strategy and filtering algorithm. The theoretical results are compared with the simulated ones     

Pulsed Wavemeter Timing Reference for Sampling Oscilloscope Calibration

A pulsed wavemeter technique is described that is useful as a source of microwave frequency sine waves for the time base calibration of sampling oscilloscopes.     

Broadband sampling oscilloscope characterization with the“Nose-to-Nose” calibration procedure: a theoretical andpractical analysis

In the past the “nose-to-nose” calibration procedure has been introduced as probably the most accurate method to determine the impulse response of broadband sampling oscilloscopes like the HP54124T. The method is based on the hypothesis “sampler kick-out equals oscilloscope impulse response”. This hypothesis was originally based on an intuitive approach and was later verified experimentally (comparison with power measurements) as well as with SPICE simulations. Until now, however, there was no generalized mathematical evidence supporting this basic hypothesis. In this paper a mathematical theory is developed, which starts from a generalized sampler equivalent scheme, and which shows that, under conditions which are valid in practice, the sampler kick-out indeed equals the sampler impulse response. Experimental results are reported concerning the accuracy and precision of the calibration procedure. These experiments involve the investigation of experiment repeatability, noise, sampler linearity and timebase effects