The new method improves accuracy in calibrations of oscilloscopes, common test instruments that measure voltage in communications and electronics devices, and potentially could boost performance and save money in other fields ranging from medical testing to structural analysis to remote sensing.
A waveform can take many different shapes, from staircase steps to irregular curves. A waveform typically is described by a single number—some key parameter of interest in a particular application. For example, engineers have described waveforms using terms such as pulse duration, or transition time between the levels representing '0' and '1' (the binary code used in digital electronics). But waveforms can be diverse and complex, especially in advanced high-speed devices, and a traditional analysis may not distinguish between similar shapes that differ in subtle ways. The result can be signal mistakes (a 1 mistaken for a 0, for instance) or misidentification of defects.
NIST's new calibration method* defines waveforms completely, providing both signal reading and measurement uncertainty at regular intervals along the entire wave, and for the first time makes waveform calibrations traceable to fundamental physics. The mathematics-intensive method is laborious and currently is performed only at NIST (which has more than 750 oscilloscopes), but the developers plan to write a software program that will automate the technique and make it transferable to other users.
The new method offers NIST calibration customers, including major manufacturers and the military, more comprehensive characterization of a greater variety of waveforms, and helps to meet current and future demands for measurements at ever-higher frequencies, data rates, and bandwidths. The impact could be far reaching. The global market for oscilloscopes is $1.2 billion. Anecdotal data suggest that for one product alone, Ethernet optical fiber transceivers, industry could save tens or even hundreds of millions of dollars through manufacturing innovations (such as the new NIST method) that reduce component reject rates and/or boost yields.
Of particular interest to scientists and engineers, the NIST calibration method incorporates new techniques for quantifying errors in waveform measurements. This allows, for the first time, accurate transfer of measurement uncertainties between the time domain (results arranged by time) and the frequency domain (the same data arranged by frequency). Researchers in many fields have long used a technique called "Fourier transform," which reveals patterns in a sequence of numbers, to transfer data from the time domain to the frequency domain. "The new NIST method is, in effect, a Fourier transform for uncertainty," says NIST physicist Paul Hale.
Although the new method was developed for common lab test instruments, it also may have applications in measuring other types of waveforms, such as those generated in electrocardiograms for medical testing, ultrasound diagnostics of structural defects and failures, speech recognition, seismology and other remote sensing activities.
* P. Hale, A. Dienstfrey, J.C.M. Wang, D.F. Williams, A. Lewandowski, D.A. Keenan and T.S. Clement. Traceable waveform calibration with a covariance-based uncertainty analysis. IEEE Transactions on Instrumentation and Measurement. Vol. 58, No. 10. Oct.
Laura Ost | EurekAlert!
Scientists create biodegradable, paper-based biobatteries
08.08.2018 | Binghamton University
Ricocheting radio waves monitor the tiniest movements in a room
07.08.2018 | Duke University
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
15.08.2018 | Physics and Astronomy
15.08.2018 | Earth Sciences
15.08.2018 | Physics and Astronomy