Towards the possibility to combine LOFAR and GNSS measurements to sense ionospheric irregularities

Author:

Flisek PawełORCID,Forte Biagio,Fallows RichardORCID,Kotulak Kacper,Krankowski Andrzej,Bisi Mario,Mevius Maaijke,Froń Adam,Tiburzi Caterina,Soida Marian,Śmierciak Bartosz,Grzesiak Marcin,Matyjasiak Barbara,Pożoga Mariusz,Dąbrowski Bartosz,Mann Gottfried,Vocks Christian,Zucca Pietro,Błaszkiewicz Leszek

Abstract

Inhomogeneities within the ionospheric plasma density affect trans-ionospheric radio signals, causing radio wave scintillation in the amplitude and phase of the signals. The amount of scintillation induced by ionospheric irregularities typically decreases with the radio wave frequency. As the ionosphere affects a variety of technological systems (e.g., civil aviation, financial operations) as well as low-frequency radio astronomy observations, it is important to detect and monitor ionospheric effects with higher accuracy than currently available. Here, a novel methodology for the detection and characterization of ionospheric irregularities is established on the basis of LOFAR (Low-Frequency Array) scintillation measurements at Very High Frequency (VHF) that take into account the lack of ergodicity in the intensity fluctuations induced by scintillation. The methodology estimates the S4 scintillation index originating from irregularities with spatial scales in the inertial sub-range of electron density fluctuations in the ionosphere. The methodology is illustrated by means of observations that were collected through the Polish LOFAR stations located in Bałdy, Borowiec and Łazy: its validation was carried out by comparing LOFAR VHF scintillation observations with independent Global Navigation Satellite Systems (GNSS) observations that were collected through a high-rate receiver located near the LOFAR station in Bałdy as well as through geodetic receivers from the Polish ASG-EUPOS network. Two case studies are presented: 31 March 2017 and 28 September 2017. The comparison between LOFAR S4 observations and independent ionospheric measurements of both scintillation and rate of change of Total Electron Content (TEC) from GNSS reveals that the sensitivity of LOFAR and GNSS to ionospheric structures is different as a consequence of the frequency dependency of radio wave scintillation. Furthermore, it can be noticed that observations of LOFAR VHF scintillation can be utilised to detect plasma structures forming in the mid-latitude ionosphere, including electron density gradients occurring over spatial scales that are not necessarily detected through traditional GNSS measurements: the detection of all spatial scales is important for correct monitoring and modelling of ionospheric processes. Hence, the different sensitivity of LOFAR to ionospheric structures, in addition to traditional GNSS ionospheric measurements, allows us to expand the knowledge of ionospheric processes.

Funder

Ministry of Education and Science of Poland

Narodowe Centrum Badań i Rozwoju

Narodowe Centrum Nauki

UK Natural Environment Research Council

Publisher

EDP Sciences

Subject

Space and Planetary Science,Atmospheric Science

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3