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The problem of wideband massive MIMO channel estimation is considered. Targeting for low complexity algorithms as well as small training overhead, a compressive sensing (CS) approach is pursued. Unfortunately, due to the Kronecker-type…

Information Theory · Computer Science 2018-03-30 Gerhard Wunder , Ingo Roth , Axel Flinth , Mahdi Barzegar , Saeid Haghighatshoar , Giuseppe Caire , Gitta Kutyniok

In this paper, we investigate the beamforming performances of holographic surfaces implemented as lossless antenna arrays with less than half-wavelength spacing. We first develop a method to quantify the mutual coupling effect among the…

Information Theory · Computer Science 2023-11-10 Peng Wang , Majid Nasiri Khormuji , Branislav M. Popovic

Time-modulated arrays (TMAs) can effectively perform beamsteering over the first positive harmonic pattern by applying progressively delayed versions of stair-step approximations of a sine waveform to the antenna excitations. In this…

Signal Processing · Electrical Eng. & Systems 2024-02-01 R. Maneiro-Catoira , J. Brégains , José A. García-Naya , L. Castedo

Low-noise phased arrays are essential for the next generation of microwave and submillimetre wave astronomy. We analyze their behaviour from a functional perspective, and show that their operation is intimately related to the mathematical…

Astrophysics · Physics 2007-07-12 S. Withington , G. Saklatvala , M. P. Hobson

In wideband near-field arrays, frequency-dependent array responses cause wavefronts at different frequencies to deviate from that at the center frequency, producing beam squint and degrading multi-user performance. True-time-delay (TTD)…

Signal Processing · Electrical Eng. & Systems 2025-11-12 Cixiao Zhang , Yin Xu , Xinghao Guo , Xiaowu Ou , Dazhi He , Wenjun Zhang

Phases of the spherical harmonic analysis of full-sky cosmic microwave background (CMB) temperature data contain useful information complementary to the ubiquitous angular power spectrum. In this letter we present a new method of phase…

Astrophysics · Physics 2009-11-16 Lung-Yih Chiang , Pavel D. Naselsky

In this paper, the design, realization, and demonstration of a broadband millimeter-wave imaging system based on the synthetic aperture radar technique (SAR) are discussed. The proposed system, operating within the frequency range of…

Applied Physics · Physics 2022-06-01 Fahimeh Sepehripour , Ahmad Shafiei Alavijeh , Mohammad Fakharzadeh , Amin Khavasi

In millimeter-wave (mmWave) MIMO systems, while a hybrid digital/analog precoding structure offers the potential to increase the achievable rate, it also faces the challenge of the need of a low-complexity design. In specific, the hybrid…

Information Theory · Computer Science 2016-03-08 Zhenyu Xiao , Pengfei Xia , Xiang-Gen Xia

We present the design and the preliminary on sky performance with respect to beams and pass-bands of a multichroic polarimeter array covering the 90 and 146 GHz Cosmic Microwave Background (CMB) bands and its enabling broadband optical…

The proliferation of large multi-antenna configurations operating in high frequency bands has recently challenged the conventional far-field, rich-scattering paradigm of wireless channels. Extra large antenna arrays must usually work in the…

Information Theory · Computer Science 2024-10-14 Adrian Agustin , Xavier Mestre

The tremendous bandwidth available in the millimeter wave (mmW) frequencies between 30 and 300 GHz have made these bands an attractive candidate for next-generation cellular systems. However, reliable communication at these frequencies…

Information Theory · Computer Science 2014-10-20 Parisa A. Eliasi , Sundeep Rangan , Theodore S. Rappaport

A digital frequency multiplexing (DfMUX) system has been developed and used to tune large arrays of transition edge sensor (TES) bolometers read out with SQUID arrays for mm-wavelength cosmology telescopes. The DfMUX system multiplexes the…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 K. MacDermid , P. Hyland , F. Aubin , E. Bissonnette , M. Dobbs , J. Hubmayr , G. Smecher , S. Warraich

Multiple-input multiple-output (MIMO) array based millimeter-wave (MMW) imaging has a tangible prospect in applications of concealed weapons detection. A near-field imaging algorithm based on wavenumber domain processing is proposed for a…

Signal Processing · Electrical Eng. & Systems 2021-01-25 Shiyong Li , Shuoguang Wang , Moeness G. Amin , Guoqiang Zhao

We report on the development of commercially fabricated multi-chroic antenna coupled Transition Edge Sensor (TES) bolometer arrays for Cosmic Microwave Background (CMB) polarimetry experiments. The orders of magnitude increase in detector…

Modern far infrared and submillimeter instruments require large format arrays. We consider the relative performance of filled array (bare pixel) and feedhorn-coupled architectures for bolometer focal planes. Based on typical array…

Astrophysics · Physics 2009-11-07 M. J. Griffin , J. J. Bock , W. K. Gear

This work presents techniques which can allow low-cost phased-array receivers to be reconfigured as interferometric imagers and thereby reducing cost. Since traditional phased arrays power combine incoming signals prior to digitization,…

Signal Processing · Electrical Eng. & Systems 2021-07-21 Vikas Chauhan

Constraining the Galactic foregrounds with multi-frequency Cosmic Microwave Background (CMB) observations is an essential step towards ultimately reaching the sensitivity to measure primordial gravitational waves (PGWs), the sign of…

In the area of near-field millimeter-wave imaging, the generalized sparse array synthesis (SAS) method is in great demand. The traditional methods usually employ the greedy algorithms, which may have the convergence problem. This paper…

Signal Processing · Electrical Eng. & Systems 2022-08-10 Shuoguang Wang , Shiyong Li , Ahmad Hoorfar , Ke Miao , Guoqiang Zhao , Houjun Sun

Fluorescence microscopy and derived techniques are continuously looking for photodetectors able to guarantee increased sensitivity, high spatial and temporal resolution and ease of integration into modern microscopy architectures. Recent…

Many experimental efforts are striving to provide deep maps of the cosmic microwave background (CMB) to shed light on key questions in modern cosmology. The primary science goal for some of these experiments is to further constrain the…

Instrumentation and Methods for Astrophysics · Physics 2024-08-14 Rustam Balafendiev , Thomas Gascard , Jon E. Gudmundsson
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