Systematic errors in digital cross correlators due to quantization and differential nonlinearity

Author

White, D. Rod ; Pickup, C.P.

Author_Institution

Dept. of Sci. & Ind. Res., Lower Hutt, New Zealand

Issue

1

fYear

1987

fDate

3/1/1987 12:00:00 AM

Firstpage

47

Lastpage

53

Abstract

The errors in digital cross correlators caused by quantization and differential nonlinearity are discussed. It is shown that if there is sufficient uncorrelated noise, the effects of quantization are negligible. Analytic expressions for errors caused by differential nonlinearity in a cross correlator measuring Gaussian noise are derived. A procedure for calibrating digital cross correlators is outlined. The results of the analysis are verified to high accuracy by computer simulation of digital cross correlators based on nonideal analog-to-digital converters. The results find direct application in high-accuracy Johnson noise thermometry.

Keywords

analogue-digital conversion; calibration; correlators; digital instrumentation; digital simulation; measurement errors; noise measurement; signal processing equipment; thermal noise; thermometers; Johnson noise thermometry; analog-to-digital converters; computer simulation; differential nonlinearity; digital cross correlators; error analysis; quantization; Correlators; Equations; Mathematical model; Measurement uncertainty; Noise; Quantization; Systematics;

fLanguage

English

Journal_Title

Instrumentation and Measurement, IEEE Transactions on

Publisher

ieee

ISSN

0018-9456

Type

jour

DOI

10.1109/TIM.1987.6312629

Filename

6312629