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Role of the filter phase in phase sampling interferometry.

Juan Antonio Quiroga1, Manuel Servín, Julio Cesar Estrada

  • 1Optics Department, Universidad Complutense de Madrid, Facultad de CC Físicas, Ciudad Universitaria s/n Madrid 28040, Spain. aq@fis.ucm.es

Optics Express
|October 15, 2011
PubMed
Summary
This summary is machine-generated.

This study explains how filter phase is crucial in linear phase sampling algorithms, particularly for complex frequency responses in least squares and recursive filters. Understanding this phase is key for accurate signal processing in interferometry.

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Area of Science:

  • Signal Processing
  • Interferometry
  • Linear Systems

Background:

  • Linear phase sampling algorithms are typically modeled as linear filters.
  • Traditional phase sampling interferometry often neglects filter phase, assuming real impulse responses.
  • Complex frequency responses arise in advanced methods like least squares and recursive filters.

Purpose of the Study:

  • To derive quadrature equations for general phase sampling algorithms.
  • To elucidate the significance of filter phase in these algorithms.
  • To address the limitations of ignoring filter phase in specific signal processing applications.

Main Methods:

  • Derivation of quadrature equations for generalized phase sampling.
  • Analysis of linear filter frequency response characteristics.
  • Investigation of impulse response properties related to filter phase.

Main Results:

  • Quadrature equations for general linear phase sampling algorithms are established.
  • The filter phase is demonstrated to play a critical role, not just its magnitude.
  • The study provides a framework for analyzing algorithms with complex frequency responses.

Conclusions:

  • The phase of the frequency response is essential for accurately characterizing linear phase sampling algorithms.
  • Ignoring filter phase can lead to inaccuracies, especially with least squares and recursive filters.
  • This work offers a more complete understanding of phase sampling, improving signal processing in interferometry.