Analysis and Implementation of a Direct Phase Unwrapping Method for Displacement Measurement Using Self-Mixing Interferometry

Self-mixing or optical feedback interferometry has been widely used for displacement and velocity measurement applications. For metric information retrieval with <; λ/2 precision, various phase unwrapping methods have been proposed. However, these are computationally heavy and require large numbe...

Full description

Saved in:
Bibliographic Details
Published in:IEEE sensors journal Vol. 17; no. 22; pp. 7425 - 7432
Main Authors: Ehtesham, Ayesha, Zabit, Usman, Bernal, Olivier D., Raja, Gulistan, Bosch, Thierry
Format: Journal Article
Language:English
Published: New York IEEE 15.11.2017
The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Institute of Electrical and Electronics Engineers
Subjects:
Algorithms
Bandwidths
Computer simulation
Displacement measurement
Electronics
Engineering Sciences
Error analysis
Hardware
Information retrieval
Interferometry
Laser feedback
Laser modes
Optical feedback
optical feedback interferometry
Optical interferometry
Optics
Phase retrieval
Phase unwrapping
Photonic
Real time
Real-time systems
self-mixing
Sensors
Velocity measurement
Phase Unwrapping
Self-Mixing
Displacement Measurement
Optical Feedback Interferometry
ISSN:1530-437X, 1558-1748
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Self-mixing or optical feedback interferometry has been widely used for displacement and velocity measurement applications. For metric information retrieval with <; λ/2 precision, various phase unwrapping methods have been proposed. However, these are computationally heavy and require large number of hardware resources, thereby hindering the development of real-time, embedded solutions for large bandwidth applications. In this regard, a simple and efficient feedback phase retrieval algorithm, called consecutive samples-based unwrapping (CSU) is presented. Detailed analysis of its error performance has been conducted as a function of key optical feedback parameters. A theoretical study has also been conducted to explain as to why such good error performance is obtained for such a simple algorithm by establishing a linear relation between the modulated laser power signal and the laser phase in the absence of optical feedback for specific ranges of key optical feedback parameters. We applied CSU on various simulated and experimentally acquired signals using SMI for the retrieval of harmonic and arbitrary displacements and found out that CSU retrieves target displacement with a precision of about λ/10 while consuming much less time and hardware resources. The paper also presents FPGA based hardware design results of CSU and compares its performance with a traditional analytical phase unwrapping method in terms of maximum clock frequency, latency, and on-chip hardware resources. This hardware comparison strongly establishes the advantages of such a fast and computationally light algorithm, readily suitable for large bandwidth, embedded, and real-time sensing applications.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 14
ISSN:1530-437X
1558-1748
DOI:10.1109/JSEN.2017.2758440