An autonomous adaptive low-power instrument platform(AAL-PIP)chain of six stations has been newly established on East Antarctic Plateau along the 40°geomagnetic meridian,to investigate interhemispheric geomagneti...An autonomous adaptive low-power instrument platform(AAL-PIP)chain of six stations has been newly established on East Antarctic Plateau along the 40°geomagnetic meridian,to investigate interhemispheric geomagnetically conjugate current systems,waves,and other space weather phenomena in Polar Regions.These six stations,PG0 to PG5,which host low-power magnetometers(Fluxgate and Searchcoil),dual frequency GPS receivers,HF radio experiment,and run autonomously with solar power and two-way satellite communication,are designated at the geomagnetically conjugate(based on the International Geomagnetic Reference Field)locations of the West Greenland geomagnetic chain covering magnetic latitudes from 70°to 80°.We present the development,deployment,and operation of this chain,as well as the data collected by the chain and some preliminary scientific results showing evidence of interhemispheric asymmetries,which are important to better understand Solar Wind–Magnetosphere–Ionosphere(SWMI)coupling in Polar Regions.Recent investigations focus on magnetic impulse(MI)events,traveling convection vortices(TCVs),and ultra-low frequency(ULF)waves in the coupled southern and northern hemispheres.展开更多
Ionospheric irregularities can adversely affect the performance of Global Navigation Satellite System (GNSS). How-ever, this opens the possibility of using GNSS as an effective ionospheric remote sensing tool. Despite...Ionospheric irregularities can adversely affect the performance of Global Navigation Satellite System (GNSS). How-ever, this opens the possibility of using GNSS as an effective ionospheric remote sensing tool. Despite ionospheric monitoring has been undertaken for decades, these irregularities in multiple spatial and temporal scales are still not fully understood. This paper reviews Virginia Tech’s recent studies on multi-scale ionospheric irregularities using ground-based and space-based GNSS observations. First, the relevant background of ionospheric irregularities and their impact on GNSS signals is reviewed. Next, three topics of ground-based observations of ionospheric irregulari-ties for which GNSS and other ground-based techniques are used simultaneously are reviewed. Both passive and active measurements in high-latitude regions are covered. Modelling and observations in mid-latitude regions are considered as well. Emphasis is placed on the increased capability of assessing the multi-scale nature of ionospheric irregularities using other traditional techniques (e.g., radar, magnetometer, high frequency receivers) as well as GNSS observations (e.g., Total-Electron-Content or TEC, scintillation). Besides ground-based observations, recent advances in GNSS space-based ionospheric measurements are briefly reviewed. Finally, a new space-based ionospheric observa-tion technique using GNSS-based spacecraft formation flying and a differential TEC method is demonstrated using the newly developed Virginia Tech Formation Flying Testbed (VTFFTB). Based on multi-constellation multi-band GNSS, the VTFFTB has been developed into a hardware-in-the-loop simulation testbed with external high-fidelity global ionospheric model(s) for 3-satellite formation flying, which can potentially be used for new multi-scale ionospheric measurement mission design.展开更多
基金Support for the development and testing of this system has been provided through a Major Research Infrastructure (MRI) Grant ATM-922979 to Virginia Tech from the National Science Foundation, USAsupport has been provided by the National Science Foundation for the operation and scientific investigation of data from the deployed AAL-PIP stations along the Antarctic 40 magnetic meridian by Grants NSF ANT-08398585, PLR-1243398, PLR-1543364 and EAR-1520864+2 种基金Support at the University of Michigan was provided by NSF grant ANT-0838861supported by NSF grant PLR-1243225 to ASTRAfinancial support through the German Ministry for Economy and Technology and the German Center for Aviation and Space (DLR) under contract 50 OC 0302
文摘An autonomous adaptive low-power instrument platform(AAL-PIP)chain of six stations has been newly established on East Antarctic Plateau along the 40°geomagnetic meridian,to investigate interhemispheric geomagnetically conjugate current systems,waves,and other space weather phenomena in Polar Regions.These six stations,PG0 to PG5,which host low-power magnetometers(Fluxgate and Searchcoil),dual frequency GPS receivers,HF radio experiment,and run autonomously with solar power and two-way satellite communication,are designated at the geomagnetically conjugate(based on the International Geomagnetic Reference Field)locations of the West Greenland geomagnetic chain covering magnetic latitudes from 70°to 80°.We present the development,deployment,and operation of this chain,as well as the data collected by the chain and some preliminary scientific results showing evidence of interhemispheric asymmetries,which are important to better understand Solar Wind–Magnetosphere–Ionosphere(SWMI)coupling in Polar Regions.Recent investigations focus on magnetic impulse(MI)events,traveling convection vortices(TCVs),and ultra-low frequency(ULF)waves in the coupled southern and northern hemispheres.
基金the AFOSR(Grant No.13-0658-09)Virginia Tech.Z.Xu and M.D.Hartinger were supported by NSF-1543364(Polar Experiment Network for Geospace Upper-atmosphere Investigations-PENGUIn:Interhemispheric Investigations along the 40-degree Magnetic Meridian)1744828(Collaborative Proposal:A High-Latitude Conjugate Area Array Experiment to Investigate Solar Wind-Magnetosphere-Ionosphere Coupling).
文摘Ionospheric irregularities can adversely affect the performance of Global Navigation Satellite System (GNSS). How-ever, this opens the possibility of using GNSS as an effective ionospheric remote sensing tool. Despite ionospheric monitoring has been undertaken for decades, these irregularities in multiple spatial and temporal scales are still not fully understood. This paper reviews Virginia Tech’s recent studies on multi-scale ionospheric irregularities using ground-based and space-based GNSS observations. First, the relevant background of ionospheric irregularities and their impact on GNSS signals is reviewed. Next, three topics of ground-based observations of ionospheric irregulari-ties for which GNSS and other ground-based techniques are used simultaneously are reviewed. Both passive and active measurements in high-latitude regions are covered. Modelling and observations in mid-latitude regions are considered as well. Emphasis is placed on the increased capability of assessing the multi-scale nature of ionospheric irregularities using other traditional techniques (e.g., radar, magnetometer, high frequency receivers) as well as GNSS observations (e.g., Total-Electron-Content or TEC, scintillation). Besides ground-based observations, recent advances in GNSS space-based ionospheric measurements are briefly reviewed. Finally, a new space-based ionospheric observa-tion technique using GNSS-based spacecraft formation flying and a differential TEC method is demonstrated using the newly developed Virginia Tech Formation Flying Testbed (VTFFTB). Based on multi-constellation multi-band GNSS, the VTFFTB has been developed into a hardware-in-the-loop simulation testbed with external high-fidelity global ionospheric model(s) for 3-satellite formation flying, which can potentially be used for new multi-scale ionospheric measurement mission design.
