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In the past few decades, the localization literature has seen many models attempting to characterize the non-line-of-sight (NLOS) bias error commonly experienced in range measurements. These models have either been based on specific…

Information Theory · Computer Science 2019-05-17 Christopher E. O'Lone , Harpreet S. Dhillon , R. Michael Buehrer

We present an unsupervised outlier detection method for galaxy spectra based on the spectrum autoencoder architecture spender, which reliably captures spectral features and provides highly realistic reconstructions for SDSS galaxy spectra.…

Instrumentation and Methods for Astrophysics · Physics 2023-08-02 Yan Liang , Peter Melchior , Sicong Lu , Andy Goulding , Charlotte Ward

Direct handset-to-satellite (DHTS) communication is emerging as a core capability of 6G non-terrestrial networks, enabling standard devices to directly access low Earth orbit (LEO) satellites. While LEO provides the physical access layer…

Emerging Technologies · Computer Science 2026-03-20 Shimaa Naser , Maryam Tariq , Raneem Abdel-Rahim , De Mi , Azzam Mourad , Hadi Otrok , Mahmoud Al-Qutayri , Ayman Elnashar , Sami Muhaidat

In high-dynamic low earth orbit (LEO) satellite communication (SATCOM) systems, frequent channel state information (CSI) acquisition consumes a large number of pilots, which is intolerable in resource-limited SATCOM systems. To tackle this…

Information Theory · Computer Science 2024-10-30 Chenlan Lin , Xiaoming Chen , Zhaoyang Zhang

We propose a novel, connectivity-oriented loss function for training deep convolutional networks to reconstruct network-like structures, like roads and irrigation canals, from aerial images. The main idea behind our loss is to express the…

Computer Vision and Pattern Recognition · Computer Science 2020-09-16 Doruk Oner , Mateusz Koziński , Leonardo Citraro , Nathan C. Dadap , Alexandra G. Konings , Pascal Fua

We develop a geometric account of sequence modelling that links patterns in the data to measurable properties of the loss landscape in transformer networks. First, we cast conditional sequence distributions into a Hilbert-space framework…

Machine Learning · Computer Science 2025-04-28 Zhongtian Chen , Daniel Murfet

The sparsity of multipaths in the wideband channel has motivated the use of compressed sensing for channel estimation. In this letter, we propose a different approach to sparse channel estimation. We exploit the fact that $L$ taps of…

Information Theory · Computer Science 2022-01-24 Woong-Hee Lee , Ki Won Sung

The integration of non-terrestrial networks (NTN) into 5G new radio (NR) has opened up the possibility of developing a new positioning infrastructure using NR signals from Low-Earth Orbit (LEO) satellites. Compared to existing Global…

The absorption by gas toward background continuum sources informs us about the cosmic density of gas components as well as the hosts responsible for the absorption (galaxies, clusters, cosmic filaments). Cosmic absorption line distributions…

Instrumentation and Methods for Astrophysics · Physics 2023-08-11 Nichole Gray , Cameron Pratt , Joel Bregman

With the anticipated increase in the number of low power base stations (BSs) deployed in small cell networks, blockage effects becoming more sensitive on wireless transmissions over high spectrums, variable propagation fading scenarios make…

Networking and Internet Architecture · Computer Science 2016-12-19 Jiaqi Chen , Fen Bin , Xiaohu Ge , Qiang Li , Cheng-Xiang Wang

This paper considers the downlink of a single-cell massive MIMO (multiple-input multiple-output) system with dual-polarized antennas at both the base station and users. We consider a channel model that takes into account several practical…

Information Theory · Computer Science 2022-06-17 Özgecan Özdogan , Emil Björnson

In this paper, we investigate the downlink transmission of a multiuser multiple-input single-output (MISO) channel under a symbol-level precoding (SLP) scheme, having imperfect channel knowledge at the transmitter. In defining the SLP…

Signal Processing · Electrical Eng. & Systems 2018-08-14 Alireza Haqiqatnejad , Farbod Kayhan , Bjorn Ottersten

Power spectral density (PSD) maps providing the distribution of RF power across space and frequency are constructed using power measurements collected by a network of low-cost sensors. By introducing linear compression and quantization to a…

Information Theory · Computer Science 2017-04-05 Daniel Romero , Seung-Jun Kim , Georgios B. Giannakis , Roberto Lopez-Valcarce

This paper presents a new method to model X-ray scattering on random rough surfaces. It combines the approaches we presented in two previous papers -- \zs\cite{zhao03} \& \pz\cite{zhao15}. An actual rough surface is (incompletely) described…

Classical Physics · Physics 2017-04-13 Ping Zhao

The acquisition of Downlink (DL) channel state information at the transmitter (CSIT) is known to be a challenging task in multiuser massive MIMO systems when uplink/downlink channel reciprocity does not hold (e.g., in frequency division…

Information Theory · Computer Science 2025-06-13 Yi Song , Tianyu Yang , Mahdi Barzegar Khalilsarai , Giuseppe Caire

In this paper we investigate the effect of Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS) propagation on the Area Spectral Efficiency (ASE) and on the energy efficiency of dense small-cell networks. We show that including both LOS and…

Networking and Internet Architecture · Computer Science 2014-09-29 Carlo Galiotto , Ismael Gomez-Miguelez , Nicola Marchetti , Linda Doyle

The integration of non-terrestrial networks (NTN) into 5G new radio (NR) enables a new class of positioning capabilities based on cellular signals transmitted by Low-Earth Orbit (LEO) satellites. In this paper, we investigate joint…

Landslide detection from high resolution satellite imagery is a critical task for disaster response and risk assessment, yet the relative effectiveness of modern segmentation architectures and finetuning strategies for this problem remains…

Computer Vision and Pattern Recognition · Computer Science 2026-04-21 Md Kowsher , Weiwei Zhan , Chen Chen

Reciprocity-based beamforming-most commonly employed in time-division duplexing-uses noisy, estimated (i.e., measured) channel state information (CSI) acquired on the uplink. While computationally efficient, reciprocity-based beamforming…

Signal Processing · Electrical Eng. & Systems 2025-03-25 Benjamin J. B. Deutschmann , Erik Leitinger , Klaus Witrisal

Accurate channel model and channel estimation are essential to empower extremely large-scale MIMO (XL-MIMO) in 6G networks with ultra-high spectral efficiency. With the sharp increase in the antenna array aperture of the XL-MIMO scenario,…

Information Theory · Computer Science 2023-04-25 Yu Lu , Linglong Dai
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