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Ground-based Doppler asymmetric spatial heterodyne interferometry retrieves upper atmospheric winds by calculating the phase shift in the interferogram resulting from the Doppler shift of airglow emission lines. However, in practical applications, interferogram distortion, such as fringe bending and tilting, can adversely affect wind accuracy. This paper presents a distortion correction method based on the resampling matrix that can be obtained from an interferogram of airglow lines or a calibration lamp. The method is straightforward to implement, capable of addressing various types of distortions, and notably reduces wind uncertainty in interferograms with low signal-to-noise ratios. Laboratory tests and field results verify that the interferograms corrected by this method not only yield accurate wind measurements but also reduce the standard deviation of retrieved wind for the average fringes corresponding to different rows of the interferogram.
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http://dx.doi.org/10.1364/AO.543493 | DOI Listing |
Sci Rep
August 2025
School of Electronic Engineering, Naval University of Engineering, Wuhan, 430000, China.
Passive radar (PR) relies on receiving signals reflected from targets by other existing noncooperative radiation sources, which are broadly divided into ground- and space-based categories, to achieve target detection and tracking. In the context of space-based PR, this paper proposes a PR using the Iridium satellite signal, which is a low-orbit satellite communication signal with global coverage. With an improved detection range and accredited ambiguity function, a PR using the Iridium satellite signal can address the issues of limited terrestrial coverage for ground-based PR and insufficient receiving power for medium- to high-orbit space-based PR.
View Article and Find Full Text PDFGround-based Doppler asymmetric spatial heterodyne interferometry retrieves upper atmospheric winds by calculating the phase shift in the interferogram resulting from the Doppler shift of airglow emission lines. However, in practical applications, interferogram distortion, such as fringe bending and tilting, can adversely affect wind accuracy. This paper presents a distortion correction method based on the resampling matrix that can be obtained from an interferogram of airglow lines or a calibration lamp.
View Article and Find Full Text PDFSci Total Environ
January 2025
Department of Geosciences, Atmospheric Science Division, Texas Tech University, Lubbock, TX, USA; National Wind Institute, Texas Tech University, Lubbock, TX, USA. Electronic address:
Understanding the kinematics of aerosol horizontal transport and vertical mixing near the surface, within the atmospheric boundary layer (ABL), and in the overlying free troposphere (FT) is critical for various applications, including air quality and weather forecasting, aviation, road safety, and dispersion modeling. Empirical evidence of aerosol mixing processes within the ABL during synoptic-scale events over arid and semiarid regions (i.e.
View Article and Find Full Text PDFPathophysiology
May 2023
Department of Physiology and Pathophysiology, Petrozavodsk State University, 33, Lenin Pr., 185910 Petrozavodsk, Russia.
The primary aim of the study was to assess cerebral circulation in healthy young subjects during an ultra-short (45 min) session of ground-based microgravity modeled by "dry" immersion (DI), with the help of a multifunctional Laser Doppler Flowmetry (LDF) analyzer. In addition, we tested a hypothesis that cerebral temperature would grow during a DI session. The supraorbital area of the forehead and forearm area were tested before, within, and after a DI session.
View Article and Find Full Text PDFDoppler asymmetric spatial heterodyne (DASH) interferometry is a novel concept for observing atmospheric winds. This paper discusses a numerical model for the simulation of fringe patterns and a methodology to correct fringe images for extracting Doppler information from ground-based DASH measurements. Based on the propagation of optical waves, the fringe pattern was modeled considering different angular deviations and optical aberrations.
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