A sound card based multi-channel frequency measurement system
Groeger, StephanPhysics Department, Université de Fribourg, Switzerland - Paul Scherrer Institute, Villigen, Switzerland
Bison, GeorgPhysics Department, Université de Fribourg, Switzerland
Knowles, Paul E.Physics Department, Université de Fribourg, Switzerland
Weis, AntoinePhysics Department, Université de Fribourg, Switzerland
2006
Published in:
The European Physical Journal: Applied Physics. - 2006, vol. 33, p. 221-224
English
For physical processes which express themselves as a frequency, for example magnetic field measurements using optically-pumped alkali-vapor magnetometers, the precise extraction of the frequency from the noisy signal is a classical problem. We describe herein a frequency measurement system based on an inexpensive commercially available computer sound card coupled with a software single-tone estimator which reaches Cramér-Rao limited performance, a feature which commercial frequency counters often lack. Characterization of the system and examples of its successful application to magnetometry are presented.