Atmospheric refraction ≈ Atmospheric refraction
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Satellite-mediated quantum atmospheric links Open
The establishment of quantum communication links over a global scale is\nenabled by satellite nodes. We examine the influence of Earth's atmosphere on\nthe performance of quantum optical communication channels with emphasis on the\ndownlin…
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An analytical formalism accounting for clouds and other ‘surfaces’ for exoplanet transmission spectroscopy Open
Although the formalism of Lecavelier des Etangs et al. (2008) is extremely\nuseful to understand what shapes transmission spectra of exoplanets, it does\nnot include the effects of a sharp change in flux with altitude generally\nassociated…
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Analytic Scattering and Refraction Models for Exoplanet Transit Spectra Open
Observations of exoplanet transit spectra are essential to understanding the physics and chemistry of distant worlds. The effects of opacity sources and many physical processes combine to set the shape of a transit spectrum. Two such key p…
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Geotechnical monitoring using total stations and laser scanners: critical aspects and solutions Open
Modern geotechnical monitoring is based on a variety of surface-based and integrated sensors. This article discusses the potential but also the limitations of total stations and laser scanners in monitoring of civil infrastructure and natu…
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Effects of refraction on transmission spectra of gas giants: decrease of the Rayleigh scattering slope and breaking of retrieval degeneracies Open
Detection of the signature of Rayleigh scattering in the transmission spectrum of an exoplanet is increasingly becoming the target of observational campaigns because the spectral slope of the Rayleigh continuum enables one to determine the…
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Estimating refractivity from propagation loss in turbulent media Open
This paper estimates lower atmospheric refractivity (M‐profile) given an electromagnetic (EM) propagation loss (PL) measurement. Specifically, height‐independent PL measurements over a range of 10–80 km are used to infer information about …
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Atmospheric bending effects in GNSS tomography Open
In Global Navigation Satellite System (GNSS) tomography, precise information about the tropospheric water vapor distribution is derived from integral measurements like ground-based GNSS slant wet delays (SWDs). Therefore, the functional re…
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Modeling infrasonic propagation through a spherical atmospheric layer—Analysis of the stratospheric pair Open
Methods are developed to calculate acoustic propagation paths through an atmospheric layer surrounding a spherical globe in order to more accurately model the propagation of infrasonic signals, which are often observed after propagating hu…
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Refraction in planetary atmospheres: improved analytical expressions and comparison with a new ray-tracing algorithm Open
Atmospheric refraction affects to various degrees exoplanet transit, lunar\neclipse, as well as stellar occultation observations. Exoplanet retrieval\nalgorithms often use analytical expressions for the column abundance along a\nray traver…
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Atmospheric Ducting Effect in Wireless Communications: Challenges and Opportunities Open
Atmospheric ducting has a significant impact on electromagnetic wave propagation. Radio signals that are trapped and guided by the atmospheric duct can travel a much longer distance over the horizon with lower attenuation since the signal …
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Long-range propagation through inhomogeneous turbulent atmosphere: analysis beyond phase screens Open
Many applications rely on the propagation of electromagnetic waves through extended regions of the atmosphere over which the refractive index can vary in a complex manner. Gradients and curvature of the mean refractive index profile result…
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Observations of Gravity Wave Refraction and Its Causes and Consequences Open
Horizontal gravity wave (GW) refraction was observed around the Andes and Drake Passage during the SouthTRAC campaign. GWs interact with the background wind through refraction and dissipation. This interaction helps to drive midatmospheric…
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The Elusive Nature of “Seeing” Open
Atmospheric image blur, “seeing”, is one of the key parameters that influences the selection of observatory sites and the performance of ground-based telescopes. In this review, the common definition of seeing based on the Kolmogorov turbu…
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A High-precision Technique to Correct for Residual Atmospheric Dispersion in High-contrast Imaging Systems Open
Direct detection and spectroscopy of exoplanets requires high contrast\nimaging. For habitable exoplanets in particular, located at small angular\nseparation from the host star, it is crucial to employ small inner working\nangle (IWA) coro…
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Correction of Atmospheric Refraction Geolocation Error for High Resolution Optical Satellite Pushbroom Images Open
When an optical remote sensing satellite is imaging the Earth in-orbit, the propagation direction of the Line of Sight (LOS) will be changed because of atmospheric refraction. This will result in a geolocation deviation on the collinear ri…
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Flexible method of refraction correction in vision measurement systems with multiple glass ports Open
Many vision measurement systems, especially in outdoor engineering, usually utilize glass ports to protect sensors against environmental influences. The refraction caused by glass ports lead to measurement errors in traditional single view…
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Atmospheric refraction corrections in ground-to-satellite optical time transfer Open
Free-space optical time and frequency transfer techniques can synchronize fixed ground stations at the femtosecond level, over distances of tens of kilometers. However, optical time transfer will be required to span intercontinental distan…
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Effects of temperature inversion in the lower atmosphere on dispersion and angle of arrival of highly directional beams Open
The performance of free-space optical applications can be improved using beams of different wavelengths for the auxiliary actions of pointing/tracking or turbulence correction. Chromatic dispersion owing to the atmosphere is an issue for m…
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ATMOSPHERICALLY COMPENSATED SHAPE FROM SHADING ON THE MARTIAN SURFACE: TOWARDS THE PERFECT DIGITAL TERRAIN MODEL OF MARS Open
We have expanded our existing Shape and Albedo from Shading framework which has primarily been used to generate Digital Terrain Models (DTMs) of the Lunar Surface. The extension consists of an atmospheric model such that the approach can b…
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An Accurate Calculation of the Atmospheric Refraction Error of Optical Remote Sensing Images Based on the Fine-Layered Light Vector Method Open
Atmospheric refraction is an important factor that affects the positioning accuracy of optical high-resolution satellite imaging. Current calculation methods do not consider regional change characteristics in the atmosphere; the atmospheri…
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Analytical ray-tracing in planetary atmospheres Open
Context. Ground-based astro-geodetic observations and atmospheric radio occultations are two examples of observational techniques requiring a scrutiny analysis of atmospheric refraction. In both cases, the measured changes of the observabl…
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BUNDLE ADJUSTMENT WITH POLYNOMIAL POINT-TO-CAMERA DISTANCE DEPENDENT CORRECTIONS FOR UNDERWATER PHOTOGRAMMETRY Open
Uncontrolled refraction of optical rays in underwater photogrammetry is known to reduce its accuracy potential. Several strategies have been proposed aiming at restoring the accuracy to levels comparable with photogrammetry applied in air.…
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Refractivity Inversions From Point‐To‐Point X‐Band Radar Propagation Measurements Open
Dynamic refractive environments within the marine atmospheric boundary layer (MABL) pose difficulties in the prediction of X‐band radar wave propagation due to natural phenomena such as evaporation ducts (ED). This study utilizes a unique …
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On the importance of astronomical refraction for modern solar astrometric measurements Open
In this work we study in details the influence of pure astronomical\nrefraction on solar metrologic measurements made from ground-based full disk\nimagery and provide the tools for correcting the measurements and estimating\nthe associated…
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The Refraction Correction of Elevation Angle for the Mean Annual Global Reference Atmosphere Open
In some frequency-sharing studies between fixed service and space radiocommunication services, including fixed-satellite, broadcasting-satellite, and space science services, it is necessary to estimate the apparent elevation angle of a spa…
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Theory of data‐driven SAR autofocus to compensate for refraction effects Open
There are challenges in attempting to acquire sufficient atmospheric measurements that are required in order to model the physical atmospheric refraction effects for all transmission pulses within a typical synthetic aperture radar (SAR) c…
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Mathematical Modeling and Accuracy Testing of WorldView-2 Level-1B Stereo Pairs without Ground Control Points Open
With very high resolution satellite (VHRS) imagery of 0.5 m, WorldView-2 (WV02) satellite images have been widely used in the field of surveying and mapping. However, for the specific WV02 satellite image geometric orientation model, there…
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Estimation of temporal variations in path-averaged atmospheric refractive index gradient from time-lapse imagery Open
The sea level vertical refractive index gradient in the U.S. Standard Atmosphere model is −2.7×10−8 m−1 at 500 nm. At any particular location, the actual refractive index gradient varies due to turbulence and local weather conditions. An i…
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Implementation of a quality control for radio occultation observations in the presence of large gradients of atmospheric refractivity Open
In preparation for the launch of the first six satellites of the COSMIC-2 mission in equatorial orbit, and the larger number of observations that such a mission will provide in the lower tropical troposphere, work is underway at the Nation…
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Refraction in exoplanet atmospheres Open
Context. Refraction deflects photons that pass through atmospheres, which affects transit light curves. Refraction thus provides an avenue to probe physical properties of exoplanet atmospheres and to constrain the presence of clouds and ha…