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This paper considers an angle-domain intelligent reflecting surface (IRS) system. We derive maximum likelihood (ML) estimators for the effective angles from the base station (BS) to the user and the effective angles of propagation from the…

Information Theory · Computer Science 2021-03-02 Xiaoling Hu , Caijun Zhong , Zhaoyang Zhang

Millimetre-wave observations represent an important tool for Cosmology studies. The Line Intensity Mapping (LIM) technique has been proposed to map in three dimensions the specific intensity due to line (e.g. [CII], CO) emission, for…

Instrumentation and Methods for Astrophysics · Physics 2023-08-29 Usasi Chowdhury , Florence Levy-Bertrand , Martino Calvo , Johannes Goupy , Alessandro Monfardini

A wide field space-based imaging telescope is necessary to fully exploit the technique of observing dark matter via weak gravitational lensing. This first paper in a three part series outlines the survey strategies and relevant instrumental…

Astrophysics · Physics 2015-06-24 Jason Rhodes , Alexandre Refregier , Richard Massey , the SNAP Collaboration

In this paper, we investigate the problem of beam alignment in millimeter wave (mmWave) systems, and design an optimal algorithm to reduce the overhead. Specifically, due to directional communications, the transmitter and receiver beams…

Information Theory · Computer Science 2017-12-29 Morteza Hashemi , Ashutosh Sabharwal , C. Emre Koksal , Ness B. Shroff

Intelligent reflecting surfaces (IRSs) improve both the bandwidth and energy efficiency of wideband communication systems by using low-cost passive elements for reflecting the impinging signals with adjustable phase shifts. To realize the…

Signal Processing · Electrical Eng. & Systems 2021-06-08 Siqi Ma , Wenqian Shen , Jianping An , Lajos Hanzo

Imaging atmospheric Cherenkov telescopes (IACTs) used for ground-based gamma-ray astronomy at TeV energies use reflectors with areas on the order of 100m$^2$ as their primary optic. These tessellated reflectors comprise hundreds of mirror…

Instrumentation and Methods for Astrophysics · Physics 2014-11-20 A. McCann , D. Hanna , J. Kildea , M. McCutcheon

With the commissioning of the refurbished adaptive secondary mirror (ASM) for the 6.5-meter MMT Observatory under way, special consideration had to be made to properly calibrate the mirror response functions to generate an interaction…

Instrumentation and Methods for Astrophysics · Physics 2024-08-14 Jacob Taylor , Robin Swanson , Parker Levesque , Masen Lamb , Amali Vaz , Manny Montoya , Andrew Gardner , Katie M. Morzinski , Suresh Sivanandam

Image regridding and coaddition have a wide range of applications in astronomical observations. {\sc Imcom}, an algorithm that provides control over point spread function (PSF) and noise in coadded images, has been found to meet the…

Instrumentation and Methods for Astrophysics · Physics 2026-01-06 Kaili Cao

The availability and performance of laser-based adaptive optics (AO) systems are strongly dependent on the power and quality of the laser beam before being projected to the sky. Frequent and time-consuming alignment procedures are usually…

Instrumentation and Methods for Astrophysics · Physics 2014-05-23 Clémentine Béchet , Andrés Guesalaga , Benoit Neichel , Vincent Fesquet , Héctor González-Núñez , Sebastián Zúñiga , Pedro Escarate , Dani Guzman

This work presents a novel adaptive framework for simultaneously estimating spacecraft attitude and sensor misalignment. Uncorrected star tracker misalignment can introduce significant pointing errors that compromise mission objectives in…

Systems and Control · Electrical Eng. & Systems 2025-07-29 Ridma Ganganath , Simone Servadio , David Lee

In this article, we introduce a novel algorithm for efficient near-field synthetic aperture radar (SAR) imaging for irregular scanning geometries. With the emergence of fifth-generation (5G) millimeter-wave (mmWave) devices, near-field SAR…

Signal Processing · Electrical Eng. & Systems 2023-05-04 Josiah Smith , Murat Torlak

Accurate photometric redshifts are among the key requirements for precision weak lensing measurements. Both the large size of the Sloan Digital Sky Survey (SDSS) and the existence of large spectroscopic redshift samples that are…

In this paper, we propose a novel framework that aims to jointly design the reflection coefficients of multiple RISs and the precoding strategy of a single BS to optimize the self-tracking of the position and the velocity of a single…

Information Theory · Computer Science 2023-04-27 Silvia Palmucci , Anna Guerra , Andrea Abrardo , Davide Dardari

Complex field measurements are increasingly becoming the standard for state-of-the-art astronomical instrumentation. Complex field measurements have been used to characterize a suite of ground, airborne, and space-based heterodyne receiver…

Instrumentation and Methods for Astrophysics · Physics 2018-09-25 Kristina K. Davis , Willem Jellema , Stephen J. C. Yates , Christopher E. Groppi , Jochem J. A. Baselmans , Andrey M. Baryshev

In millimeter wave cellular communication, fast and reliable beam alignment via beam training is crucial to harvest sufficient beamforming gain for the subsequent data transmission. In this paper, we establish fundamental limits in…

Information Theory · Computer Science 2017-05-22 Chunshan Liu , Min Li , Stephen V. Hanly , Iain B. Collings , Philip Whiting

Millimeter wave communications rely on narrow-beam transmissions to cope with the strong signal attenuation at these frequencies, thus demanding precise beam alignment between transmitter and receiver. The communication overhead incurred to…

Information Theory · Computer Science 2017-02-22 Muddassar Hussain , Nicolo Michelusi

A near-field wideband communication system is investigated in which a base station (BS) employs an extra-large scale antenna array (ELAA) to serve multiple users in its near-field region. To facilitate near-field multi-user beamforming and…

Information Theory · Computer Science 2024-09-24 Zhaolin Wang , Xidong Mu , Yuanwei Liu

We propose a new instrumental concept for long-baseline optical single-mode interferometry using integrated optics which were developed for telecommunication. Visible and infrared multi-aperture interferometry requires many optical…

Astrophysics · Physics 2009-10-31 F. Malbet , P. Kern , I. Schanen-Duport , J. -P. Berger , K. Rousselet-Perraut

The integral field spectrograph configuration of the LMIRCam science camera within the Large Binocular Telescope Interferometer (LBTI) facilitates 2 to 5 $\mu$m spectroscopy of directly imaged gas-giant exoplanets. The mode, dubbed ALES,…

Instrumentation and Methods for Astrophysics · Physics 2018-08-09 Jordan M. Stone , Andrew J. Skemer , Philip Hinz , Zack Briesemeister , Travis Barman , Charles E. Woodward , Mike Skrutskie , Jarron Leisenring

It has long been known that galaxy shapes align coherently with the large-scale density field. Characterizing this effect is essential to interpreting measurements of weak gravitational lensing, the deflection of light from distant galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-17 Sukhdeep Singh , Ali Shakir , Yesukhei Jagvaral , Rachel Mandelbaum
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