English
Related papers

Related papers: Using the antenna impedance to estimate soil elect…

200 papers

Atmospheric emission is a dominant source of disturbance in ground-based astronomy at mm wavelengths. The Antarctic plateau is recognized to be an ideal site for mm and sub-mm observations, and the French/Italian base of Dome C is among the…

The ALMA North American and European prototype antennas have been evaluated by a variety of measurement systems to quantify the major performance specifications. Nearfield holography was used to set the reflector surfaces to 17 microns RMS.…

Empirical path loss models are defined for a specific antenna system used during measurements and characterized by a particular radiation pattern and main lobe beam width. In this paper, we propose a novel approach to modifying such a model…

For the past several decades, numerous attempts have been made to model the climate of Mars with extensive studies focusing on the planet's dynamics and the understanding of its climate. While physical modeling and data assimilation…

Earth and Planetary Astrophysics · Physics 2023-09-06 Nour Abdelmoneim , Dattaraj B. Dhuri , Dimitra Atri , Germán Martínez

A three-dimensional model of a novel plasma based electrically small antenna is developed for investigating the gas properties and antenna parameters under a low pressure, low plasma temperature environment. The antenna exhibits dipole…

Plasma Physics · Physics 2026-04-10 Samsud Moon

Radio interferometers can potentially detect the sky-averaged signal from the Cosmic Dawn (CD) and the Epoch of Reionisation (EoR) by studying the Moon as a thermal block to the foreground sky. The first step is to mitigate the Earth-based…

Instrumentation and Methods for Astrophysics · Physics 2023-12-19 Himanshu Tiwari , Benjamin McKinley , Cathryn M. Trott , Nithyanandan Thyagarajan

Line intensity mapping is a promising probe of the universe's large-scale structure. We explore the sensitivity of the DSA-2000, a forthcoming array consisting of over 2000 dishes, to the statistical power spectrum of neutral hydrogen's 21…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-28 Ruby Byrne , Nivedita Mahesh , Gregg W. Hallinan , Liam Connor , Vikram Ravi , T. Joseph W. Lazio

The use of Immersed Gratings offers advantages for both space- and ground-based spectrographs. As diffraction takes place inside the high-index medium, the optical path difference and angular dispersion are boosted proportionally, thereby…

Instrumentation and Methods for Astrophysics · Physics 2015-10-16 Michiel Rodenhuis , Paul J. J. Tol , Tonny H. M. Coppens , Phillip P. Laubert , Aaldert H. van Amerongen

The formation of the first stars and galaxies during 'Cosmic Dawn' is thought to have imparted a faint signal onto the 21-cm spin temperature from atomic Hydrogen gas in the early Universe. Observationally, an absorption feature should be…

Instrumentation and Methods for Astrophysics · Physics 2022-11-30 Danny C. Price

We derive synthetic electrical conductivity, seismic velocity, and density distributions from the results of martian mantle convection models affected by basin-forming meteorite impacts. The electrical conductivity features an intermediate…

Earth and Planetary Astrophysics · Physics 2021-02-09 Thomas Ruedas , Doris Breuer

Moisture estimation of sub-surface soil and the overlaying biomass layer is pivotal in precision agriculture and wildfire risk assessment. However, the characterization of layered material is nontrivial due to the radar…

Signal Processing · Electrical Eng. & Systems 2024-04-01 Ishfaq Aziz , Elahe Soltanaghai , Adam Watts , Mohamad Alipour

This paper considers antenna impedance estimation based on training sequences at MIMO receivers. The goal is to firstly leverage extensive resources available in most wireless systems for channel estimation to estimate antenna impedance in…

Information Theory · Computer Science 2023-08-30 Shaohan Wu , Brian L. Hughes

Soil moisture conditions can influence the evolution of a tropical cyclone (TC) that is partially or completely over land. Hence, better constraining soil moisture initial conditions in a numerical weather prediction model can potentially…

Atmospheric and Oceanic Physics · Physics 2023-08-01 Jana Kolassa , Manisha Ganeshan , Erica McGrath-Spangler , Oreste Reale , Rolf Reichle , Sara Q. Zhang

We investigate the prospect of constraining scalar field dark energy models using HI 21-cm intensity mapping surveys. We consider a wide class of coupled scalar field dark energy models whose predictions about the background cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 Azam Hussain , Shruti Thakur , Tapomoy Guha Sarkar , Anjan A Sen

All 21-cm signal experiments rely on electronic receivers that affect the data via both multiplicative and additive biases through the receiver's gain and noise temperature. While experiments attempt to remove these biases, the residuals of…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-14 Keith Tauscher , David Rapetti , Bang D. Nhan , Alec Handy , Neil Bassett , Joshua Hibbard , David Bordenave , Richard F. Bradley , Jack O. Burns

Understanding large-angular-scale galactic foregrounds is crucial for future CMB experiments aiming to detect $B$-mode polarization from primordial gravitational waves. Traditionally, the dust component has been separated using its…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-18 Guangyu Zhang , Chi-Ting Chiang , Chris Sheehy , Anže Slosar , Jian Wang

The high-redshift 21-cm signal of neutral hydrogen is expected to be observed within the next decade and will reveal epochs of cosmic evolution that have been previously inaccessible. Due to the lack of observations, many of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-16 Aviad Cohen , Anastasia Fialkov , Rennan Barkana

By using the satelital information of Earth observation unloaded by a station constructed in the country and reflectances measurements of the soil, we found the total radiation attenuation of the atmosphere for a small region of the…

Atmospheric and Oceanic Physics · Physics 2012-08-02 Camilo Delgado-Correal , José E. García

The paper introduces a novel approach for estimating soil moisture in vegetated surfaces, specifically focusing on sugarcane crops throughout various growth stages in agriculture applications. While existing models typically address bare…

Signal Processing · Electrical Eng. & Systems 2024-12-17 Gian Oré , Jhonnatan Yepes , Juliana A. Góes , Luciano P. Oliveira , Bárbara Teruel , Hugo E. Hernandez-Figueroa

The 21 cm intensity mapping (IM) technique provides us with an efficient way to observe the cosmic large-scale structure (LSS). From the LSS data, one can use the baryon acoustic oscillation and redshift space distortion to trace the…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-07 Peng-Ju Wu , Yichao Li , Jing-Fei Zhang , Xin Zhang