scholarly journals Measured Response of Local, Mid-range and Far-range Discontinuities of Large Metal Groundplanes using Time Domain Techniques

2005 ◽  
Vol 3 ◽  
pp. 99-103
Author(s):  
T. Schrader ◽  
K. Münter ◽  
S. Battermann ◽  
H. Garbe
Keyword(s):  
Time Domain ◽  
Electromagnetic Compatibility ◽  
Dynamic Range ◽  
High Dynamic Range ◽  
Test Site ◽  
Scattering Parameter ◽  
Time Domain Signal ◽  
Complex Valued ◽  
Measured Response ◽  
Antenna Calibration

Abstract. This work describes a method to detect and to quantify any local or mid-range discontinuity on extended flat metal planes. Often these planes are used for antenna calibration (open area test site - OATS) or the plane could be the ground of a semi-anechoic chamber used in Electromagnetic Compatibility (EMC) testing. The measurement uncertainty of antenna calibration or EMC testing depends on the groundplane's quality, which can be accessed using this method. A vector network analyzer with time-domain option is used to determine the complex-valued input scattering parameter S11,F of an aperture antenna in a monostatic setup. S11,F contains the information desired about the discontinuities and is measured in the frequency domain with high dynamic range. But only after a linear filtering utilizing the Chirp-Z-Transform the obtained time-domain signal S11,T evidence of local and mid-range discontinuities.

scholarly journals High dynamic-range magnetic resonance spectroscopy (MRS) time-domain signal analysis

2009 ◽  
Vol 62 (4) ◽  
pp. 1026-1035 ◽  
Author(s):  
William C. Hutton ◽  
G. Larry Bretthorst ◽  
Joel R. Garbow ◽  
Joseph J.H. Ackerman
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Time Domain ◽  
Signal Analysis ◽  
Dynamic Range ◽  
High Dynamic Range ◽  
Resonance Spectroscopy ◽  
Time Domain Signal ◽  
High Dynamic

scholarly journals Statistical View on Phase and Magnitude Information in Signal Processing

2012 ◽  
Vol 47 (3) ◽  
pp. 127-136
Author(s):  
Waldemar Popiński
Keyword(s):  
Signal Processing ◽  
Time Domain ◽  
Signal Reconstruction ◽  
Time Domain Signal ◽  
Reconstructed Signal ◽  
Band Pass ◽  
Expected Values ◽  
Random Fluctuations ◽  
Phase Distortions ◽  
Complex Valued

Statistical View on Phase and Magnitude Information in Signal ProcessingIn this work the problem of reconstruction of an original complex-valued signalot,t= 0, 1, …,n- 1, from its Discrete Fourier Transform (DFT) spectrum corrupted by random fluctuations of magnitude and/or phase is investigated. It is assumed that the magnitude and/or phase of discrete spectrum values are distorted by realizations of uncorrelated random variables. The obtained results of analysis of signal reconstruction from such distorted DFT spectra concern derivation of the expected values and bounds on variances of the reconstructed signal at the observation moments. It is shown that the considered random distortions in general entail change in magnitude and/or phase of the reconstructed signal expected values, which together with imposed random deviations with finite variances can blur the similarity to the original signal. The effect of analogous random amplitude and/or phase distortions of a complex valued time domain signal on band pass filtration of distorted signal is also investigated.

Multispectral, high dynamic range, time domain continuous imaging

2018 ◽  
Vol 2018 (5) ◽  
pp. 409-1-409-9
Author(s):  
Henry Dietz ◽  
Paul Eberhart ◽  
Clark Demaree
Keyword(s):  
Time Domain ◽  
Dynamic Range ◽  
High Dynamic Range ◽  
High Dynamic

scholarly journals A low-noise high dynamic-range time-domain EMI measurement system for CISPR Band E

2011 ◽  
Vol 9 ◽  
pp. 309-315
Author(s):  
C. Hoffmann ◽  
P. Russer
Keyword(s):  
Real Time ◽  
Measurement System ◽  
Time Domain ◽  
Dynamic Range ◽  
Digital Signal ◽  
High Dynamic Range ◽  
Low Noise ◽  
Noise Floor ◽  
Multi Stage ◽  
Analog To Digital Conversion

Abstract. In this paper, a broadband time-domain EMI measurement system for measurements from 9 kHz to 18 GHz is presented that allows for compliant EMI measurements in CISPR Band E. Combining ultra-fast analog-to-digital-conversion and real-time digital signal processing on a field-programmable-gate-array (FPGA) with ultra-broadband multi-stage down-conversion, scan times can be reduced by several orders of magnitude in comparison to a traditional heterodyne EMI-receiver. The ultra-low system noise floor of 6–8 dB and the real-time spectrogram allow for the characterisation of the time-behaviour of EMI near the noise floor. EMI measurements of electronic consumer devices and electric household appliances are presented.

High-dynamic-range 3D shape measurement based on time domain superposition

2019 ◽  
Vol 30 (6) ◽  
pp. 065004 ◽  
Author(s):  
Liang Zhang ◽  
Qian Chen ◽  
Chao Zuo ◽  
Tianyang Tao ◽  
Yuzhen Zhang ◽  
...  
Keyword(s):  
Time Domain ◽  
Dynamic Range ◽  
High Dynamic Range ◽  
Shape Measurement ◽  
3D Shape ◽  
3D Shape Measurement ◽  
High Dynamic

scholarly journals High Dynamic Range Externally Time-Gated Photon Counting Optical Time-Domain Reflectometry

2019 ◽  
Vol 37 (23) ◽  
pp. 5899-5906 ◽  
Author(s):  
Bin Li ◽  
Guangwei Deng ◽  
Ruiming Zhang ◽  
Zhonghua Ou ◽  
Heng Zhou ◽  
...  
Keyword(s):  
Time Domain ◽  
Dynamic Range ◽  
Photon Counting ◽  
High Dynamic Range ◽  
Time Domain Reflectometry ◽  
Optical Time Domain Reflectometry ◽  
High Dynamic ◽  
Optical Time

Advantageous Apodization Functions for Magnitude-Mode Fourier Transform Spectroscopy

1987 ◽  
Vol 41 (1) ◽  
pp. 93-98 ◽  
Author(s):  
Judy P. Lee ◽  
Melvin B. Comisarow
Keyword(s):  
Fourier Transform ◽  
Time Domain ◽  
Dynamic Range ◽  
Signal To Noise Ratio ◽  
Time Domain Signal ◽  
Time Domain Data ◽  
Window Functions ◽  
Fourier Transform Spectra ◽  
The Time Domain ◽  
Ratio Reduction

A systematic examination of the efficacy of window functions for reducing the spectral skirt of magnitude-mode Fourier transform spectra is reported. The efficacy is examined for the general case of a damped time-domain signal, with specific cases ranging from undamped to essentially completely damped signals. The choice of the optimal window is dependent upon the required dynamic range and the amount of damping in the time-domain data. For a dynamic range of less than 100:1 and moderate damping, the Hamming window is the window of choice. For larger dynamic ranges or greater damping, the 3-term Blackman-Harris window and the Kaiser-Bessel window are the windows of choice. The 3-term Blackman-Harris window is preferred for a dynamic range of 1,000:1 and the Kaiser-Bessel window is preferred for a dynamic range of 10,000:1. The sensitivity (signal-to-noise ratio) reduction for windows is reported for a damping range from zero to essentially complete damping. All windows examined have the same sensitivity reduction within 25%.

Sign in / Sign up

Export Citation Format

Share Document