Share Email Print

Proceedings Paper

Investigations on the frequency measuring error of laser Doppler velocimeters using the quadrature demodulation technique
Author(s): Juergen W. Czarske; O. Doelle
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

We present the application of the quadrature demodulation technique (QDT) for time-resolved frequency measurements in laser Doppler velocimetry (LDV). In contrast to conventional frequency estimators like FFT, the QDT allows the determination of the Doppler frequency nearly independent of the number of the occurring signal periods, so that a high time resolution can be achieved. The resulting frequency error of the QDT is investigated in dependence on relevant LDV signal parameters like SNR and time duration. Furthermore, the optimum averaging time for the processing of gaussian burst signals was determined. The minimum frequency uncertainty of the QDT occurs for an averaging time of the approximately equals 1/e burst duration at the thermal noise, and the approximately equals 1/e2 burst duration at shot noise, respectively.

Paper Details

Date Published: 19 July 1999
PDF: 2 pages
Proc. SPIE 3749, 18th Congress of the International Commission for Optics, (19 July 1999); doi: 10.1117/12.354907
Show Author Affiliations
Juergen W. Czarske, Laser Zentrum Hannover e.V. (Germany)
O. Doelle, Laser Zentrum Hannover e.V. (Germany)

Published in SPIE Proceedings Vol. 3749:
18th Congress of the International Commission for Optics
Alexander J. Glass; Joseph W. Goodman; Milton Chang; Arthur H. Guenther; Toshimitsu Asakura, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?