High level white noise generator
Abstract
A wide band, stable, random noise source with a high and well-defined output power spectral density is provided which may be used for accurate calibration of Johnson Noise Power Thermometers (JNPT) and other applications requiring a stable, wide band, well-defined noise power spectral density. The noise source is based on the fact that the open-circuit thermal noise voltage of a feedback resistor, connecting the output to the input of a special inverting amplifier, is available at the amplifier output from an equivalent low output impedance caused by the feedback mechanism. The noise power spectral density level at the noise source output is equivalent to the density of the open-circuit thermal noise or a 100 ohm resistor at a temperature of approximately 64,000 Kelvins. The noise source has an output power spectral density that is flat to within 0.1% (0.0043 db) in the frequency range of from 1 KHz to 100 KHz which brackets typical passbands of the signal-processing channels of JNPT's. Two embodiments, one of higher accuracy that is suitable for use as a standards instrument and another that is particularly adapted for ambient temperature operation, are illustrated in this application.
- Inventors:
-
- Oak Ridge, TN
- Knoxville, TN
- Issue Date:
- Research Org.:
- Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
- OSTI Identifier:
- 863455
- Patent Number(s):
- 4175258
- Assignee:
- United States of America as represented by United States (Washington, DC)
- Patent Classifications (CPCs):
-
G - PHYSICS G01 - MEASURING G01R - MEASURING ELECTRIC VARIABLES
H - ELECTRICITY H03 - BASIC ELECTRONIC CIRCUITRY H03B - GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER
- DOE Contract Number:
- W-7405-ENG-26
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- level; white; noise; generator; wide; band; stable; random; source; well-defined; output; power; spectral; density; provided; accurate; calibration; johnson; thermometers; jnpt; applications; requiring; based; open-circuit; thermal; voltage; feedback; resistor; connecting; input; special; inverting; amplifier; available; equivalent; impedance; caused; mechanism; 100; ohm; temperature; approximately; 64; 000; kelvins; flat; 0043; db; frequency; range; khz; brackets; typical; passbands; signal-processing; channels; embodiments; accuracy; suitable; standards; instrument; particularly; adapted; ambient; operation; illustrated; application; spectral density; wide band; noise source; johnson noise; temperature operation; applications requiring; particularly adapted; ambient temperature; frequency range; output power; amplifier output; output impedance; random noise; feedback resistor; source output; density level; white noise; ohm resistor; processing channels; accurate calibration; /331/
Citation Formats
Borkowski, Casimer J, and Blalock, Theron V. High level white noise generator. United States: N. p., 1979.
Web.
Borkowski, Casimer J, & Blalock, Theron V. High level white noise generator. United States.
Borkowski, Casimer J, and Blalock, Theron V. Mon .
"High level white noise generator". United States. https://www.osti.gov/servlets/purl/863455.
@article{osti_863455,
title = {High level white noise generator},
author = {Borkowski, Casimer J and Blalock, Theron V},
abstractNote = {A wide band, stable, random noise source with a high and well-defined output power spectral density is provided which may be used for accurate calibration of Johnson Noise Power Thermometers (JNPT) and other applications requiring a stable, wide band, well-defined noise power spectral density. The noise source is based on the fact that the open-circuit thermal noise voltage of a feedback resistor, connecting the output to the input of a special inverting amplifier, is available at the amplifier output from an equivalent low output impedance caused by the feedback mechanism. The noise power spectral density level at the noise source output is equivalent to the density of the open-circuit thermal noise or a 100 ohm resistor at a temperature of approximately 64,000 Kelvins. The noise source has an output power spectral density that is flat to within 0.1% (0.0043 db) in the frequency range of from 1 KHz to 100 KHz which brackets typical passbands of the signal-processing channels of JNPT's. Two embodiments, one of higher accuracy that is suitable for use as a standards instrument and another that is particularly adapted for ambient temperature operation, are illustrated in this application.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1979},
month = {1}
}