Sampling, quantization and computational aspects of the quadrature lock-in amplifier

Leis, John and Kelly, Christopher and Buttsworth, David (2012) Sampling, quantization and computational aspects of the quadrature lock-in amplifier. In: 6th International Conference on Signal Processing and Communication Systems (ICSPCS 2012) , 12-14 Dec 2012, Gold Coast, Australia.

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The phase-sensitive or 'lock-in' amplifier is a fundamental tool in experimental physics, and is able to extract exceedingly small signals in the presence of noise. The lock-in operates on the principle of synchronous excitation of the system under test, which effectively moves the desired system response above the influence of 1/f noise.
The purpose of the paper is twofold: (i) to investigate the numerical aspects of implementation of the lock-in signal processing, particularly for computationally resource-constrained environments; and (ii) to investigate the tradeoff between A/D resolution and oversampling rates in this particular application, where a synchronous reference signal is available. We conclude that the quantization, sampling rate, and numerical precision aspects are somewhat interrelated when the best possible performance in terms of noise rejection is required.

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Item Type: Conference or Workshop Item (Commonwealth Reporting Category E) (Paper)
Refereed: Yes
Item Status: Live Archive
Additional Information: Copyright © 2012 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.
Faculty/School / Institute/Centre: Historic - Faculty of Engineering and Surveying - Department of Electrical, Electronic and Computer Engineering
Date Deposited: 06 May 2013 00:38
Last Modified: 14 Aug 2014 04:42
Uncontrolled Keywords: signal processing; lockin amplifier; instrumentation; measurement
Fields of Research : 09 Engineering > 0906 Electrical and Electronic Engineering > 090603 Industrial Electronics
09 Engineering > 0906 Electrical and Electronic Engineering > 090609 Signal Processing
01 Mathematical Sciences > 0101 Pure Mathematics > 010106 Lie Groups, Harmonic and Fourier Analysis
Socio-Economic Objective: B Economic Development > 86 Manufacturing > 8615 Instrumentation > 861501 Industrial Instruments
Identification Number or DOI: 10.1109/ICSPCS.2012.6507974

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