Article
Multidisciplinary Sciences
Dongzi Li, Anna Bilous, Scott Ransom, Robert Main, Yuan-Pei Yang
Summary: Spider pulsars are millisecond pulsars with short-period orbits and low-mass companion stars. The magnetic field of the companion strongly influences the evolution of the binary system and the pulsar emission properties. The magnetic field in the spider system increases near the eclipse, as evidenced by changes in rotation measure.
Article
Astronomy & Astrophysics
J. Mena-Parra, C. Leung, S. Cary, K. W. Masui, J. F. Kaczmarek, M. Amiri, K. Bandura, P. J. Boyle, T. Cassanelli, J. -f. Cliche, M. Dobbs, V. M. Kaspi, T. L. Landecker, A. Lanman, J. L. Sievers
Summary: This paper presents a clock stabilization system that transfers the reference clock of the CHIME digital backend from a GPS-disciplined ovenized crystal oscillator to a passive hydrogen maser. By combining the stability of the GPS clock with the maser, it reduces clock timing errors for VLBI calibration observations. The system is validated and meets the stability requirements for CHIME/FRB Outriggers.
ASTRONOMICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Hailan He, Guowu Yuan, Hao Zhou, Chengming Tan, Shaojie Guo
Summary: This paper proposes an automatic recognition and localization method based on a lightweight object detection model for solar radio burst events. Experimental results demonstrate that the proposed method achieves high accuracy and recall rates, while operating at a fast detection speed.
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
(2023)
Article
Engineering, Electrical & Electronic
Cherif Diouf, Gerard J. M. Janssen, Han Dun, Tarik Kazaz, Christian C. J. M. Tiberius
Summary: This article introduces a testbed for wideband radio signal acquisition, designed for validation and demonstration of high accuracy ranging and positioning. The platform supports tight time and frequency synchronization, with multiple USRPs and a bandwidth up to 320 MHz.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Astronomy & Astrophysics
David Alonsa
Summary: We study the impact of linear order cosmological perturbations on the dispersion measure (DM) of electromagnetic pulses and calculate the power spectrum of DM-based cosmological observables. Most relativistic effects have limited impact on large angular scales and are negligible for ongoing and planned observational programs targeting fast radio bursts.
Article
Engineering, Aerospace
F. N. Minta, S. I. Nozawa, K. Kozarev, A. Elsaid, A. Mahrous
Summary: The Egypt-Alexandria station serves as a reference for other stations within the e-CALLISTO network. Despite the low solar activity, the newly installed CALLISTO spectrometer detected multiple solar radio bursts, including type II, type III, and type V bursts. A case study was conducted to validate the recorded events, and the instrument's capacity to provide real-time solar radio transient data was examined. As a result, the instrument has become an integral part of space weather monitoring and forecasting over the region and other parts of the globe.
ADVANCES IN SPACE RESEARCH
(2023)
Article
Astronomy & Astrophysics
Artem Koval, Aleksander Stanislavsky, Marian Karlicky, Bing Wang, Serge Yerin, Aleksander Konovalenko, Miroslav Barta
Summary: On July 25, 2014, a type II burst was observed using radio telescopes UTR-2 and GURT. The burst exhibited various spectral features, including fundamental and harmonic components, band splitting, a herringbone structure, and a spectral break. The herringbone pattern was analyzed to study electron density turbulence in the solar corona. It was also noted that the second type II burst consisted of three drifting lanes, which coincided with the spectral break in the first burst. This suggests that the CME/shock-streamer interaction played a role in the occurrence of the type II burst.
ASTROPHYSICAL JOURNAL
(2023)
Article
Remote Sensing
Yu. V. Yasyukevich, A. S. Yasyukevich, E. I. Astafyeva
Summary: Solar Radio Bursts (SRBs) are a significant hazard for global navigation satellite systems (GNSS), prompting system developers to upgrade equipment such as GPS to improve accuracy and noise resistance. The modernization of GPS with new-generation equipment has shown improvements in signal strength during extreme solar flares, potentially enhancing GPS stability.
Article
Astronomy & Astrophysics
Lei Liu, Zhijun Xu, Zhen Yan, Weimin Zheng, Yidan Huang, Zhong Chen
Summary: VOLKS2, a transient search tool for VLBI observations, utilizes geodetic VLBI data processing to eliminate RFIs by filtering candidate signals with multiple windows within a baseline and cross matching with multiple baselines. Parallelized with MPI and accelerated with GPU, it achieves comparable performance as autospectrum-based pipelines.
ASTRONOMICAL JOURNAL
(2021)
Article
Computer Science, Information Systems
Tuo Wu, Cunhua Pan, Yijin Pan, Hong Ren, Maged Elkashlan, Cheng-Xiang Wang
Summary: In this study, we investigate the positioning problem of multiple mobile users (MUs) in millimeter wave (mmWave) systems aided by reconfigurable intelligent surface (RIS). We propose a novel residual convolution network regression (RCNR) learning algorithm to estimate the 3D position of the MUs with higher accuracy by processing the space-time channel response vector (STCRV) as a novel type of fingerprint. Extensive simulations demonstrate that the proposed RCNR algorithm outperforms the traditional convolution neural network (CNN).
IEEE WIRELESS COMMUNICATIONS LETTERS
(2023)
Article
Astronomy & Astrophysics
Wei Su, Yan Wang, Chen Zhou, Lingfeng Lu, Ze-Bing Zhou, T. M. Li, Tong Shi, Xin-Chun Hu, Ming-Yue Zhou, Ming Wang, Hsien-Chi Yeh, Han Wang, P. F. Chen
Summary: TianQin is a proposed space-borne gravitational-wave observatory aiming to detect GWs in the frequency range of 0.1 mHz-1 Hz. The study focuses on analyzing the optical path difference (OPD) noises, finding that the OPD noises for the TDI combinations can be neglected in the most sensitive frequency range of TianQin.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
N. Lewandowska, P. B. Demorest, M. A. McLaughlin, P. Kilian, T. H. Hankins
Summary: We investigated the dispersion measure (DM) of the Main Pulse and Interpulse components of the Crab pulsar using bright, single pulses. We developed two methods using cross-correlation functions (CCFs) to determine the DM with high accuracy. The results show differences in DM between the Main Pulse, the Low Frequency Interpulse, and the High Frequency Interpulse. We also discovered a relationship between the brightness of single pulses in the High Frequency Interpulse and their DM.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Stella Koch Ocker, James M. Cordes, Shami Chatterjee, Chen-Hui Niu, Di Li, James W. McKee, Casey J. Law, Chao-Wei Tsai, Reshma Anna-Thomas, Ju-Mei Yao, Marilyn Cruces
Summary: The repeating fast radio burst FRB 20190520B is localized to a nearby galaxy. The observed dispersion measure and scattering phenomena provide support for a novel technique for estimating FRB redshifts and are consistent with previous findings.
ASTROPHYSICAL JOURNAL
(2022)
Article
Computer Science, Information Systems
Marco Cook, Angelos Marnerides, Chris Johnson, Dimitrios Pezaros
Summary: With the increasing interconnectivity and automation of operational technology (OT) systems, the threat of cyber attacks on critical national infrastructure (CNI) sectors, particularly industrial control systems (ICS), has intensified. Unlike information technology (IT) systems, ICS have unique cyber-physical characteristics, making them attractive targets due to the potential physical consequences of attacks. The field of ICS digital forensics is under-developed compared to IT digital forensics, but its importance is growing in response to the increasing need to respond to and learn from attacks.
IEEE COMMUNICATIONS SURVEYS AND TUTORIALS
(2023)
Article
Chemistry, Analytical
Abdulkadir Uzun, Firas Abdul Ghani, Amir Mohsen Ahmadi Najafabadi, Husnu Yenigun, Ibrahim Tekin
Summary: This paper presents an indoor positioning system using GPS signals in the 433 MHz ISM band, demonstrated experimentally under both line-of-sight and non-line-of-sight conditions on a building floor. The system utilizes down-converting repeaters and an up-converting receiver to transmit and receive GPS signals effectively for indoor positioning.