Broadband digital lock-in amplifier techniques

Using only commercially available equipment, we have developed simple digital lock‐in techniques that surpass the capabilities of analog lock‐in amplifiers. We describe both dual‐channel and single‐channel digital lock‐ins that are capable of measurement at any harmonic or subharmonic of the reference frequency. The best of these digital lock‐ins operates over a frequency range from dc to 400 kHz with lower phase noise and better flexibility, stability, and orthogonality than any analog lock‐in amplifier.

[1]  S Cova,et al.  Versatile digital lock-in detection technique: application to spectrofluorometry and other fields. , 1979, The Review of scientific instruments.

[2]  J. Toney,et al.  Low‐frequency computerized lock‐in amplifier , 1982 .

[3]  Harold S. Johnston,et al.  Digital Phase Sensitive Detector , 1968 .

[4]  H. Alles,et al.  Software emulated multichannel lock‐in detector , 1973 .

[5]  Lawrence G. Rubin,et al.  The new(?) wave: Digital lock‐in amplifiers , 1988 .

[6]  T G Matheson,et al.  Microprocessor assisted real-time harmonic analysis by minicomputer. , 1978, The Review of scientific instruments.

[7]  P. Probst,et al.  Low-frequency digital lock-in amplifier , 1985 .

[8]  Paul Horowitz,et al.  The Art of Electronics , 1980 .

[9]  An efficient digital phase‐sensitive detector for use in electron‐spin‐resonance spectroscopy , 1984 .

[10]  W. Gwinn,et al.  Digital modulator and synchronous demodulator system: an alternative to the analog phase detector. , 1978, The Review of scientific instruments.

[11]  A Sotgiu,et al.  Microcomputer based phase sensitive detector , 1981 .

[12]  J. Saniie,et al.  Digital phase detection based on in-phase and quadrature sampling , 1983 .

[13]  G. Stefanini,et al.  Digital techniques applied to phase-sensitive detection , 1983 .

[14]  Jorge Berger,et al.  Personal computer as an inexpensive lock‐in analyzer operating at very low frequencies , 1983 .

[15]  J. Overweg,et al.  An on-line digital phase sensitive detector in the range 2 mHz-2 kHz , 1983 .

[16]  S. Nagel,et al.  Wide‐frequency specific heat spectrometer , 1987 .

[17]  F. DeRosa.  Digital phase‐sensitive detector using a Z80A single‐board computer , 1986 .