2006/02/15 by E. Tatulli, J.-B. Le Bouquin, J. -B. LeBouquin
Computer Science · Engineering · Physics and Astronomy · #Adaptive optics and wavefront sensing #Advanced Measurement and Metrology Techniques #Astronomical interferometer #Computer science #Detector #Estimator #Fourier transform #Interferometry #Optical measurement and interference techniques #Optics #Physics #Spectral density #Telecommunications #Telescope #Visibility #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2006.10203.x
published as Mon.Not.Roy.Astron.Soc.368:1159-1168,2006 · 10 pages, 5 figures. Accepted in MNRAS
arxiv created 2006/02/15 · openalex publication_date 2006/04/13 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
There are several solutions to code the signal arising from optical long-baseline multi-aperture interferometers. In this paper, we focus on the non-homothetic spatial coding scheme (multi-axial) with the fringe pattern coded along one dimension on one detector (all-in-one). After describing the physical principles governing single-mode interferometers using that sort of recombination scheme, we analyse two different existing methods that measure the source visibility. The first technique, the so-called Fourier estimator, consists of integrating the high-frequency peak of the power spectral density of the interferogram. The second method, the so-called model-based estimator, has been specifically developed for the Astronomical Multi-BEam combineR (AMBER) instrument of the Very Large Telescope Interferometer (VLTI) and deals with directly modelling the interferogram recorded on the detector. Performances of both estimators are computed in terms of the signal-to-noise ratio (S/N) of the visibility, assuming that the interferograms are perturbed by photon and detector noises. Theoretical expressions of the visibility S/N are provided, validated through numerical computations and then compared. We show that the model-based estimator offers up to 5 times better performances than the Fourier one.