Principles of lock-in detection

  Enquire / contact me

Description of lock-in detection both in the time and in the frequency domain

Industrial Equipment & Supplies

Principles of lock-in detection
Principles of lock-in detection

Lock-in amplifiers were invented in the 1930’s and commercialized in the mid 20th century as electrical instruments capable of extracting signal amplitudes and phases in extremely noisy environments. They employ a homodyne detection scheme and
low-pass filtering to measure a signal’s amplitude and phase relative to a periodic reference.

A lock-in measurement extracts signals in a defined frequency band around the reference frequency, efficiently rejecting all other frequency components. The best instruments on the market today have a dynamic reserve of 120 dB , which means they are capable of accurately measuring a signal in the presence of noise up to a million times higher in amplitude than the signal of interest. This document provides a quick introduction to the principles of lock-in amplification and explains the most important measurement settings. The lock-in detection technique is described both in the time and in the frequency domain. Moreover, details are laid out on how signal modulation can be exploited in order to improve on signal-to-noise ratio (SNR) while keeping acquisition time low. Finally, recent innovations are discussed and the state of the art is described.

Posted on February 13, 2017 - (37295 views)
Zurich Instruments Ltd
Technoparkstrasse 1
8005 - Switzerland
+41-44-515 0410
+41-44-515 0419-
View full company profile
Location
Related articles
Two Part Epoxy Adhesive
Joint Rod Configurator
Laminar Flow System
Traco Power Opens a New Branch in France
Industrial inkjet printers
Burckhardt and ExxonMobil Signed Global Lubrications Collaboration Agreement
FIVE-YEAR SOLE SUPPLY AGREEMENT FOR EXXONMOBIL AND INFINIS
Bosch Packaging Technology Honored for its Filling and Closing Machine AFG500
Buttons and switches
High performance epoxy system
Hannay Reel Hose and Cable Reels
Digital multimeter, Carrying case and Weller Gas Soldering Iron
JDN Mini 24/07
System-based High Precision Linkages
Hannay Works Here
FANDIS' FF Series of Filter Fans
SAFETY? That's our top Priority
The Reel That Works as Hard as you
Constant Force Spring and Clip For Carbon Brush Holder Application
Maximum Efficiency Please.