IMPLEMENTATION OF A HIGH-FREQUENCY DIGITAL LOCK-IN AMPLIFIER

M.O. SONNAILLON; RAÚL URTEAGA; FABIÁN J. BONETTO; MARTÍN ORDOÑEZ

Saskatoon, Saskatchewan Canada

Conferencia; 18th Canadian Conference on Electrical and Computer Engineering; 2005

A high-frequency digital lock-in amplifier that uses nonuniform sampling is proposed and validated experimentally. By using a random sampling strategy, it is possible to process periodic signals of frequencies several times greater than the Nyquist frequency, which is given by the sampling theorem. The implemented instrument, based on a digital signal processor and its associated hardware, is described in this paper. Experimental results show the advantages of the proposed lock-in.