Results 71 to 80 of about 2,236 (212)

Radix-2 Self-Recursive Sparse Factorizations of Delay Vandermonde Matrices for Wideband Multi-Beam Antenna Arrays

IEEE Access, 2020
This paper presents a self-contained factorization for the Vandermonde matrices associated with true-time delay based wideband analog multi-beam beamforming using antenna arrays. The proposed factorization contains sparse and orthogonal matrices.
Sirani M. Perera, Arjuna Madanayake, Renato J. Cintra   +2 more
doaj   +1 more source

Backward Darts and the Subsequent Scattered Discharges Occurring Along Lightning Positive Leader Branches

Journal of Geophysical Research: Atmospheres, Volume 131, Issue 10, 28 May 2026.
Abstract We used the LOw‐Frequency ARray (LOFAR) to identify two new types of lightning discharges occurring along the tracks of earlier positive leaders. The first is a kind of intracloud dart leader that we call a “backward dart” whose behavior appears counterintuitive given the positive polarity of the channel, as they are negative dart leaders that
Bin Wu, Brian M. Hare, Olaf Scholten, Ningyu Liu, Joe Dwyer, Steve Cummer, Marten Lourens, Chris Sterpka, Paulina Turekova   +8 more
wiley   +1 more source

On Linearly Constrained Minimum Variance Beamforming [PDF]

, 2015
Beamforming is a widely used technique for source localization in signal processing and neuroimaging. A number of vector-beamformers have been introduced to localize neuronal activity by using magnetoencephalography (MEG) data in the literature ...
Liu, Chao, Zhang, Jian
core   +1 more source

OTFS transceiver design and sparse doubly-selective CSI estimation in analog and hybrid beamforming aided mmWave MIMO systems

, 2022
Orthogonal time frequency space (OTFS) waveform based millimeter wave (mmWave) MIMO systems are capable of achieving high data rates in high-mobility scenarios. Hence, transceivers are designed for both analog beamforming (AB) and hybrid beamforming (HB),
Srivastava, Suraj, Kumar Singh, Rahul, Chockalingam, A., Jagannatham, Aditya K., Hanzo, Lajos   +4 more
core   +1 more source

Temporal Variations in Seismic Ambient Noise Identify Seasonal Changes in Basal Conditions at Sermeq Kujalleq in Kangia, Greenland

Geophysical Research Letters, Volume 53, Issue 10, 28 May 2026.
Abstract Subglacial processes are key to glacier dynamics but remain poorly constrained due to limited in situ observations. We use continuous seismic and Global Navigation Satellite System (GNSS) measurements to investigate summer basal conditions at Sermeq Kujalleq in Kangia (SKK; Jakobshavn Isbræ), Kalaallit Nunaat (Greenland).
Janneke van Ginkel, Adrien Wehrlé, Ana Nap, Fabian Walter, Andrea Kneib‐Walter, Hugo Rousseau, Martin P. Lüthi   +6 more
wiley   +1 more source

Distributed processing of a fractal array beamformer

, 2013
Fractals have been proven as potential candidates for satellite flying formations, where its different elements represent a thinned array. The distributed and low power nature of the nodes in this network motivates distributed processing when using such ...
Weiss, Stephan, Corr, Jamie, I.K. Proudler, S. Weiss, Karagiannakis, Philippos, J. Corr, P. Karagiannakis, Thompson, Keith, K. Thompson, Proudler, Ian K.   +9 more
core   +1 more source

Sound source localization and speech enhancement with sparse Bayesian learning beamforming [PDF]

, 2018
Speech localization and enhancement involves sound source mapping and reconstruction from noisy recordings of speech mixtures with microphone arrays.
Christensen, Mads Græsbøll; id_orcid, Boldt, Jesper Bünsow, Jesper Bünsow Boldt, Xenaki, Angeliki, Mads Græsbøll Christensen, Angeliki Xenaki   +5 more
core   +1 more source

Symbol‐Level GRAND‐Assisted Detection for Polar‐Coded Spatial Modulation in MIMO Systems

International Journal of Communication Systems, Volume 39, Issue 7, 10 May 2026.
This research presents an integrated polar‐coded spatial modulation (PCSM) transceiver scheme for MIMO transmission over Rayleigh fading channels. The proposed architecture employs linear spatial signal processing for antenna and symbol estimation, followed by symbol‐level guessing random additive noise decoding (symbol‐level GRAND)–assisted detection ...
Abhilasha Gautam, Prabhat Thakur, Ghanshyam Singh   +2 more
wiley   +1 more source

Two stage beamforming and combining scheme for FDD massive MIMO systems with multi‐antenna users

IET Communications
This paper proposes a two‐stage beamforming and combining scheme in frequency division duplex (FDD) massive multiple‐input multiple‐output (MIMO) systems with multi‐antenna users.
Wu Zheng, Chen Liu, Yunchao Song, Tianbao Gao   +3 more
doaj   +1 more source

Optimization of Sparse Cross Array Synthesis via Perturbed Convex Optimization

Sensors, 2020
Three-dimensional (3-D) imaging sonar systems require large planar arrays, which incur hardware costs. In contrast, a cross array consisting of two perpendicular linear arrays can also support 3-D imaging while dramatically reducing the number of sensors.
Boxuan Gu, Yaowu Chen, Rongxin Jiang, Xuesong Liu   +3 more
doaj   +1 more source