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1. A novel approach for low mutual coupling and ultra-compact Two Port MIMO antenna development for UWB wireless application

Author:
Felix Urimubenshi; Dominic B.O. Konditi; Jean de Dieu Iyakaremye; Pierre Moukala Mpele; Augustin Munyaneza
Source:
Heliyon 2022 v.8 no.3 pp. e09057
ISSN:
2405-8440
Subject:
antennae,   etc   ; couplings; dimensions; microwave radiation; microwave treatment; wavelengths;     Show all 6 Subjects
Abstract:
... In this paper, a novel MIMO antenna operating in the UWB frequency band is presented. The proposed new antenna shape is derived from the conventional circular ring patch antenna having a partial ground plane. An array of three Quad-G Shaped Metamaterial structures was used between the antenna elements of the two-port MIMO antenna to expand the bandwidth in the lower frequency band of UWB applicati ...
DOI:
10.1016/j.heliyon.2022.e09057

2. Phase Mismatch Calibration for Dual-Channel Sliding Spotlight SAR-GMTI

Author:
Zhenning Zhang; Weidong Yu; Mingjie Zheng; Liangbo Zhao; Zi-Xuan Zhou
Source:
Remote Sensing 2022 v.14 no.3 pp. -
ISSN:
2072-4292
Subject:
antennae,   etc   ; data collection; geometry; remote sensing; synthetic aperture radar;     Show all 5 Subjects
Abstract:
... This article investigates channel phase mismatch calibration during the application of displaced-phase-center antenna (DPCA) in dual-channel sliding spotlight synthetic aperture radar (SAR) for ground moving target indication (GMTI). In sliding spotlight SAR, the utilization of beam progressive sweeping in azimuth causes antenna phase centers to be misaligned from the sensor path, resulting in the ...
DOI:
10.3390/rs14030617

3. Microwave radiation associated with stepped leaders of negative cloud-to-ground flashes

Author:
Shamsul Ammar Shamsul Baharin; Mohd Riduan Ahmad; Taha Raad Khaleel Al-Shaikhli; Muhammad Abu Bakar Sidik; Muhammad Haziq Mohammad Sabri; Ammar Ahmed Nasser Al-Kahtani; Sulaiman Ali Mohammad; Gaopeng Lu; Hongbo Zhang; Vernon Cooray
Source:
Atmospheric research 2022 v.270 pp. 106091
ISSN:
0169-8095
Subject:
antennae,   etc   ; avalanches; duration; electrons; microwave radiation; microwave treatment; research; sampling; stems;     Show all 9 Subjects
Abstract:
... In this paper, Very-High Frequency (VHF) and microwave radiation pulses associated with stepped leader pulses (conventional breakdown) are examined. A total of 100 stepped leader pulses (SLPs) with the associated 100 quiet periods (QPs) from ten negative cloud-to-ground (CG) flashes within the reversal distance (<8 km) have been analyzed. The QP is defined as the period between two SLPs when no el ...
DOI:
10.1016/j.atmosres.2022.106091

4. A Spherical “Earth–Ionosphere” Model for Deep Resource Exploration Using Artificial ELF-EM Field

Author:
Fanghua Zheng; Qingyun Di; Changmin Fu
Source:
Remote Sensing 2022 v.14 no.13 pp. -
ISSN:
2072-4292
Subject:
antennae,   etc   ; Earth ionosphere; electrical conductivity; exhibitions; fields; mathematical models; methodology; remote sensing; solutions; surfaces;     Show all 10 Subjects
Abstract:
... Fully coupled lithosphere, atmosphere, and ionosphere theory has demonstrated that extremely low-frequency electromagnetic (ELF-EM) fields present a broad application prospect in deep resource exploration, but previous studies have ignored the contribution of the Earth’s curvature. This study extends the theory of ELF-EM over a stratified Earth to the case where the Earth’s curvature must be taken ...
DOI:
10.3390/rs14133088

5. On the Processing of Dual-Channel Receiving Signals of the LuTan-1 SAR System

Author:
Haoyu Lin; Yunkai Deng; Heng Zhang; Dacheng Liu; Da Liang; Tingzhu Fang; Robert Wang
Source:
Remote Sensing 2022 v.14 no.3 pp. -
ISSN:
2072-4292
Subject:
antennae,   etc   ; data collection; image analysis; remote sensing; research; satellites; synthetic aperture radar; testing; theoretical models; wills;     Show all 10 Subjects
Abstract:
... LuTan-1 (LT-1) is an innovative spaceborne radar Earth observation mission including two satellites equipped with synthetic aperture radar (SAR) which will be launched in 2022. Active phased array antennas that can be divided into two physical channels are equipped on each satellite. The signal can be transmitted through the full antenna without broadening and recorded by each channel. Therefore, ...
DOI:
10.3390/rs14030515

6. Inducing molecular reactions by selective vibrational excitation of a remote antenna with near-infrared light

Author:
Cláudio M. Nunes; Nelson A. M. Pereira; Luís P. Viegas; Teresa M. V. D. Pinho e Melo; Rui Fausto
Source:
Chemical communications 2021 v.57 no.75 pp. 9570-9573
ISSN:
1364-548X
Subject:
antennae,   etc   ; chemical communication; moieties;     Show all 3 Subjects
Abstract:
... We demonstrate here that selective vibrational excitation of a moiety, remotely attached in relation to the molecular reaction site, might offer a generalized strategy for inducing bond-breaking/bond-forming reactions with exquisite precision. As a proof-of-principle, the electrocyclic ring-expansion of a benzazirine to a ketenimine was induced, in a cryogenic matrix, by near-IR light tuned at the ...
DOI:
10.1039/d1cc03574f

7. Estimation and Analysis of BDS2 and BDS3 Differential Code Biases and Global Ionospheric Maps Using BDS Observations

Author:
Min Li; Yunbin Yuan
Source:
Remote Sensing 2021 v.13 no.3 pp. -
ISSN:
2072-4292
Subject:
antennae,   etc   ; exhibitions; monitoring; remote sensing; satellites;     Show all 5 Subjects
Abstract:
... Following the continuous and stable regional service of BDS2, the BDS3 officially announced its global service in July 2020. To fully take advantage of the new multi-frequency BDS3 signals in ionosphere sensing and positioning, it is essential to understand the characteristics of the differential code bias (DCB) of new BDS3 signals and BDS performance in global ionospheric maps (GIMs) estimation. ...
DOI:
10.3390/rs13030370

8. A novel ultra-wide band wearable antenna under different bending conditions for electronic-textile applications

Author:
Mariam El Gharbi; Marc Martinez-Estrada; Raul Fernández-García; Saida Ahyoud; Ignacio Gil
Source:
The journal of the Textile Institute 2021 v.112 no.3 pp. 437-443
ISSN:
1754-2340
Subject:
antennae,   etc   ; design; dielectrics; fabrics; journals; topology;     Show all 6 Subjects
Abstract:
... This paper is devoted to a novel textile ultra-wideband (UWB) antenna for wearable applications. The antenna is designed and implemented on a felt textile substrate with attractive features such as a flexible full embroidered topology and a low dielectric loss. In this study, the UWB antenna is evaluated through the reflection coefficient (S11), gain, efficiency and effects of bending. The UWB ope ...
DOI:
10.1080/00405000.2020.1762326

9. High gain modified Vivaldi vehicular antenna for IoV communications in 5G network

Author:
Ankush Kapoor; Pradeep Kumar; Ranjan Mishra
Source:
Heliyon 2022 v.8 no.5 pp. e09336
ISSN:
2405-8440
Subject:
antennae,   etc   ; design; evolution; internet of things;     Show all 4 Subjects
Abstract:
... While targeting the sixth generation (6G) wireless communication which incorporates mainly the Internet of Things (IoT), the Internet of Vehicles (IoV) becomes a vital component to be implemented. A vehicular antenna is designed by using the modified design of the Vivaldi antenna that can cover all the frequency bands for the long-term evolution (LTE) and the mid-band fifth-generation (5G) wireles ...
DOI:
10.1016/j.heliyon.2022.e09336

10. Simulation of reflected signals in dual-position radar systems

Author:
Timur Sabitov; Aleksey Kiselev; Maksim Stepanov; Margarita Oreshkina
Source:
Remote sensing letters 2021 v.12 no.11 pp. 1082-1089
ISSN:
2150-7058
Subject:
antennae,   etc   ; models; radar; remote sensing; supply;     Show all 5 Subjects
Abstract:
... The problem of modelling reflections from targets for radar systems with two receiving antennas with spaced phase centres and overlapping directional patterns is considered. The conditions that must be met by the emitter matrix are obtained, which provides the ability to independently simulate the target in the desired position for each antenna. A configuration of a matrix consisting of five point ...
DOI:
10.1080/2150704X.2021.1964708

11. A shorting-pin based compact meander multiband printed monopole antenna

Author:
Jeremiah O. Abolade; Dominic B.O. Konditi
Source:
Heliyon 2021 v.7 no.11 pp. e08390
ISSN:
2405-8440
Subject:
antennae,   etc   ; methodology; portable equipment; prototypes; radio;     Show all 5 Subjects
Abstract:
... The antenna presented in this work is based on a meandering monopole patch antenna with the incorporated shorting-pin technique for the realization of multiband antenna. The proposed antenna is printed on an FR4 with a footprint of 0.22λg×0.36λg at the lowest operating frequency. The antenna proposed demonstrated six resonances with suitable bandwidth as well as gain which make it suitable for WiM ...
DOI:
10.1016/j.heliyon.2021.e08390

12. A novel wearable wideband antenna for application in wireless medical communication systems with jeans substrate

Author:
Farzad Khajeh-Khalili; Yasaman Khosravi
Source:
The journal of the Textile Institute 2021 v.112 no.8 pp. 1266-1272
ISSN:
1754-2340
Subject:
antennae,   etc   ; communications technology; design; electroplating; fabrics; journals; wavelengths;     Show all 7 Subjects
Abstract:
... In this paper, a novel wearable wideband antenna for application in wireless medical communication systems (0.9–6 GHz) is designed. For bandwidth enhancement, five parallel metal plates (PMPs) are placed on the top of the antenna’s patch without any disturbing effects on the performances. With the help of the proposed method, the bandwidth has been increased by about 3 GHz in comparison with the c ...
DOI:
10.1080/00405000.2020.1809909

13. Broadband Plasmon Nanofocusing: Comprehensive Study of Broadband Nanoscale Light Source

Author:
Koki Taguchi; Takayuki Umakoshi; Shota Inoue; Prabhat Verma
Source:
Journal of physical chemistry 2021 v.125 no.11 pp. 6378-6386
ISSN:
1932-7455
Subject:
antennae,   etc   ; fields; geometry; journals; mathematical models; physical chemistry; wavelengths;     Show all 7 Subjects
Abstract:
... Plasmonics, particularly the one based on plasmon resonances in optical antennas for the excitation of localized and enhanced light fields, have enabled numerous nanophotonics applications over the past few decades. One of the most common applications is to generate a nanoscale light source through plasmon resonance. An alternative phenomenon that has recently gained increasing attention for creat ...
DOI:
10.1021/acs.jpcc.0c11541

14. Perfect Control of Diffraction Patterns with Phase-Gradient Metasurfaces

Author:
Yuxiang Wang; Yueyi Yuan; Guohui Yang; Xumin Ding; Qun Wu; Yannan Jiang; Shah Nawaz Burokur; Kuang Zhang
Source:
ACS applied materials & interfaces 2022 v.14 no.14 pp. 16856-16865
ISSN:
1944-8252
Subject:
antennae,   etc   ; control methods; design; energy; materials; methodology; prediction; solutions;     Show all 8 Subjects
Abstract:
... Phase-gradient metasurfaces (PGMs) constitute an efficient platform for deflection of a beam in a desired direction. According to the generalized Snell’s law, the direction of the reflected/refracted wave can be tuned by the spatial phase function provided by the PGMs. However, most studies on PGM focus only on a single diffraction order, that is, the incident wave can be reflected or refracted to ...
DOI:
10.1021/acsami.2c00742

15. Ultra-Wideband Imaging via Frequency Diverse Array with Low Sampling Rate

Author:
Zhonghan Wang; Yaoliang Song; Yitong Li
Source:
Remote Sensing 2022 v.14 no.5 pp. -
ISSN:
2072-4292
Subject:
antennae,   etc   ; filters; image analysis; remote sensing; sampling; system optimization;     Show all 6 Subjects
Abstract:
... Imaging systems based on millimeter waves (mm-waves) are advancing to achieve higher resolution and wider bandwidth. However, a large bandwidth requires high sample rates, which may limit the development of ultra-wideband imaging systems. In this letter, we introduce the concept of frequency diverse array (FDA) into mm-wave imaging systems. In particular, we propose an ultra-wideband imaging metho ...
DOI:
10.3390/rs14051271

16. Sequential 90° Rotation of Dual-Polarized Antenna Elements in Linear Phased Arrays with Improved Cross-Polarization Level for Airborne Synthetic Aperture Radar Applications

Author:
Diego Lorente; Markus Limbach; Bernd Gabler; Héctor Esteban; Vicente E. Boria
Source:
Remote Sensing 2021 v.13 no.8 pp. -
ISSN:
2072-4292
Subject:
antennae,   etc   ; clothing; measurement; remote sensing; synthetic aperture radar; topology;     Show all 6 Subjects
Abstract:
... In this work, a novel rotation approach for the antenna elements of a linear phased array is presented. The proposed method improves by up to 14 dB the cross-polarization level within the main beam by performing a sequential 90° rotation of the identical array elements, and achieving measured cross-polarization suppressions of 40 dB. This configuration is validated by means of simulation and measu ...
DOI:
10.3390/rs13081430

17. A Moving Target Velocity Estimation Method Based on the MC-MASA SAR Mode

Author:
Yamin Wang; Jie Chen; Wei Liu; Chunsheng Li; Wei Yang
Source:
Remote Sensing 2021 v.13 no.9 pp. -
ISSN:
2072-4292
Subject:
antennae,   etc   ; geometry; image analysis; interferometry; remote sensing; synthetic aperture radar;     Show all 6 Subjects
Abstract:
... Imaging position shift based on the multiple azimuth squint angles (MASA) mode is effective for target azimuth velocity estimation, whereas accuracy is low when target range velocity is high. In this paper, the estimation problem for both target azimuth and range velocities is considered based on the multi-channels MASA (MC-MASA) mode. Firstly, the acquisition geometry of MC-MASA mode and Doppler ...
DOI:
10.3390/rs13091632

18. An Indoor Positioning and Tracking Algorithm Based on Angle-of-Arrival Using a Dual-Channel Array Antenna

Author:
Chenhui Li; Jie Zhen; Kanglong Chang; Aigong Xu; Huizhong Zhu; Jianxin Wu
Source:
Remote Sensing 2021 v.13 no.21 pp. -
ISSN:
2072-4292
Subject:
antennae,   etc   ; accuracy; algorithms; environment; filters; remote sensing; variance covariance matrix; wheels;     Show all 8 Subjects
Abstract:
... The angular position measurement of an array antenna based on a wireless signal has high accuracy in an indoor no-occlusion environment. However, due to the high complexity of indoor environments, signal occlusion, multipath, and other interfering factors are inevitable when users move randomly, which can greatly reduce the positioning accuracy. In addition, different directions of the positioning ...
DOI:
10.3390/rs13214301

19. A Low Complexity Detector for Massive MIMO Uplink Systems

Author:
Mahmoud A. Albreem
Source:
National Academy science letters 2021 v.44 no.6 pp. 545-549
ISSN:
0250-541X
Subject:
antennae,   etc   ; business enterprises; communications technology; detectors; energy efficiency; exhibitions; methodology; solutions;     Show all 8 Subjects
Abstract:
... Fifth generation wireless communication system is implemented by several mobile companies where important technologies are employed such as the massive multiple-input multiple-output (MIMO). Although it improves the spectrum and energy efficiencies, it is not a trivial to propose an efficient detector for massive MIMO systems because a large number of antennas increases the computational complexit ...
DOI:
10.1007/s40009-020-01034-7

20. Consistency Analysis of the GNSS Antenna Phase Center Correction Models

Author:
Renyu Zhou; Zhigang Hu; Qile Zhao; Hongliang Cai; Xuanzuo Liu; Chengyi Liu; Guangxing Wang; Haoyu Kan; Liang Chen
Source:
Remote Sensing 2022 v.14 no.3 pp. -
ISSN:
2072-4292
Subject:
antennae,   etc   ; calibration; couplings; exhibitions; field experimentation; latitude; models; remote sensing; robots; solutions;     Show all 10 Subjects
Abstract:
... For the same antenna type, numerical differences among the phase center correction (PCC) models released by different institutes can reach several millimeters, which is far beyond the nominal calibration accuracy. This contribution introduces a new method to evaluate the consistency of these PCC models. We first investigated the coupling of phase center offset (PCO) and phase center variation (PCV ...
DOI:
10.3390/rs14030540