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One of the main goals of the COROT mission is to get precise photometric observations of selected bright stars in order to allow the modelling of their interior through asteroseismology. However, in order to interpret the…

Astrophysics · Physics 2009-11-11 M. Gillon , P. Magain

Microwave phased array antennas (PAAs) are very attractive to defense applications and high-speed wireless communications for their abilities of fast beam scanning and complex beam pattern control. However, traditional PAAs based on phase…

High-frequency wideband cellular communications over mmWave and sub-THz offer the opportunity for high data rates. However, it also presents high path loss, resulting in limited coverage. High-gain beamforming from the antenna array is…

Information Theory · Computer Science 2024-08-14 Ozlem Yildiz , Ahmad AlAmmouri , Jianhua Mo , Younghan Nam , Elza Erkip , Jianzhong , Zhang

Long-baseline interferometry detects fringes created by superposition of two beams of light collected by two telescopes pointing into a common direction. The external path difference generated by pointing away from the zenith is commonly…

Astrophysics · Physics 2008-11-26 Richard J. Mathar

This work presents a concept for the localisation of Lamb waves using a Passive Phased Array (PPA). A Warped Frequency Transformation (WFT) is applied to the acquired signals using numerically determined phase velocity information to…

Applied Physics · Physics 2021-10-14 Luke Pollock , Graham Wild

This paper explores the potential of near-field beamforming (NFBF) in integrated sensing and communication (ISAC) systems with extremely large-scale arrays (XL-arrays). The large-scale antenna arrays increase the possibility of having…

Signal Processing · Electrical Eng. & Systems 2023-08-15 Kaiqian Qu , Shuaishuai Guo , Nasir Saeed

Accurate astrometry and photometry of saturated and coronagraphic point spread functions (PSFs) are fundamental to both ground- and space-based high contrast imaging projects. For ground-based adaptive optics imaging, differential…

Astrophysics · Physics 2008-11-26 C. Marois , D. Lafreniere , B. Macintosh , R. Doyon

To meet the requirements for high data rates and ubiquitous connectivity in 6G networks, higher frequencies and larger array apertures are employed to enhance spatial resolution and spectral efficiency. This evolution leads to an expansion…

Signal Processing · Electrical Eng. & Systems 2026-04-03 Shupei Zhang , Boya Di , Lingyang Song

Ultrasound imaging often suffers from image degradation stemming from phase aberration, which represents a significant contributing factor to the overall image degradation in ultrasound imaging. Frequency-space prediction filtering or FXPF…

Image and Video Processing · Electrical Eng. & Systems 2023-08-24 Mostafa Sharifzadeh , Habib Benali , Hassan Rivaz

Communication systems at millimeter-wave (mmW) and sub-terahertz frequencies are of increasing interest for future high-data rate networks. One critical challenge faced by phased array systems at these high frequencies is the efficiency of…

Signal Processing · Electrical Eng. & Systems 2022-02-18 Benjamin W. Domae , Ruifu Li , Danijela Cabric

Wavefront sensing involves estimating the phase and intensity of light, enabling a wide range of imaging applications, from adaptive optics and astronomy to biomedical imaging. Since conventional image sensors can only measure the spatial…

Image and Video Processing · Electrical Eng. & Systems 2026-04-07 Nebiyou Yismaw , Vishwanath Saragadam , Aswin C. Sankaranarayanan , M. Salman Asif

Image plane beam combination in optical interferometers multiplexes the interference fringes from multiple baselines onto a single detector. The beams of starlight are arranged in a non-redundant pattern at the entrance of the combiner so…

Instrumentation and Methods for Astrophysics · Physics 2022-02-16 Daniel J. Mortimer , David F. Buscher

BPM (Beam Position Measurement) system is one of the most important beam diagnostic instruments in accelerators. A fully digital BPM (DBPM) has been designed for SSRF (Shanghai Synchrotron Radiation Facility). As Analog-to-Digital Converter…

Instrumentation and Detectors · Physics 2019-09-30 Weihao Wu , Lei Zhao , Erlei Chen , Shubin Liu , Qi An

The apodizing phase plate (APP) is a solid-state pupil optic that clears out a D-shaped area next to the core of the ensuing PSF. To make the APP more efficient for high-contrast imaging, its bandwidth should be as large as possible, and…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Frans Snik , Gilles Otten , Matthew Kenworthy , Matthew Miskiewicz , Michael Escuti , Christopher Packham , Johanan Codona

The observed variations in profiles of the interstellar aromatic infrared bands correlate with the object type and are indicative of PAH populations existing i n different sources. Spectroscopic studies on PAHs can provide tools for the int…

Astrophysics · Physics 2009-11-13 Amit Pathak , Shantanu Rastogi

Phased array antennas (PAAs) possessing broadband beamforming capabilities are crucial for advanced radar and wireless communication systems. Nevertheless, traditional phase-shifter-based PAA beamformers frequently encounter the beam-squint…

Optics · Physics 2025-02-14 Mian Wang , Wenxin Zhang , Zeyu Ren , Shangyuan Li , Xiaoping Zheng , Xiaoxiao Xue

Direct imaging of exoplanets relies on complex wavefront sensing and control architectures. In addition to fast adaptive optics systems, most of the future high-contrast imaging instruments will soon be equipped with focal plane wavefront…

At very low frequencies, the new pan-European radio telescope LOFAR is opening the last unexplored window of the electromagnetic spectrum for astrophysical studies. The revolutionary APERTIF phased arrays that are about to be installed on…

Integrated optics are used to achieve astronomical interferometry inside robust and compact materials, improving the instrument's stability and sensitivity. In order to perform differential phase measurements at the H$\alpha$ line (656.3…

Motivated by future automotive applications, we study some joint radar target detection and parameter estimation problems where the transmitter, equipped with a mono-static MIMO radar, wishes to detect multiple targets and then estimate…

Signal Processing · Electrical Eng. & Systems 2020-09-21 Lorenzo Gaudio , Mari Kobayashi , Giuseppe Caire , Giulio Colavolpe