Ionospheric tomography using ADS-B signals

Abstract

Numerical modeling has demonstrated that Automatic Dependent Surveillance Broadcast (ADS-B) signals can be used to reconstruct two-dimensional (2-D) electron density maps of the ionosphere using techniques for computerized tomography. Ray tracing techniques were used to determine the characteristics of individual waves, including the wave path and the state of polarization at the satellite receiver. The modeled Faraday rotation was computed and converted to total electron content (TEC) along the raypaths. The resulting TEC was used as input for computerized ionospheric tomography (CIT) using algebraic reconstruction technique. This study concentrated on reconstructing mesoscale structures 25-100 km in horizontal extent. The primary scientific interest of this study was to show that ADS-B signals can be used as a new source of data for CIT to image the ionosphere and to obtain a better understanding of magneto-ionic wave propagation.

Ionospheric Sounding and Tomography Using Automatic Identification System (AIS) and Other Signals of Opportunity

“…Since this paper is primarily interested in AIS signals, we use the altitude of the Iridium NEXT constellation satellites at 781‐km orbital altitude. The results in the next section will be shown to be consistent with those published by Cushley and Noël (). In order to compare the results from ADS‐B and AIS, we assume the AIS orbit to be the same orbit that originally was studied for ADS‐B.…”

“…Cushley and Noël () examined case studies using the method described in this manuscript to evaluate ADS‐B signals as a potential source of TEC data to complement the existing ground‐based GPS ionospheric TEC data as well as an independent source for determining electron density maps of the ionosphere. In their work they described the ionosphere tomography results using the slant TEC data simulated from an ADS‐B system—25 aircraft as ADS‐B transmitters and one satellite at the altitude of 1,000 km as ADS‐B receiver.…”

“…The average magnetic field is computed using the International Geomagnetic Reference Field (IGRF) model data (International association of geomagnetism and aeronomy, Working Group V‐MOD, ). Although the magnetic field can be treated more accurately using the method described in Cushley, Noël, et al (), IGRF can be considered sufficient for this concept demonstration and can be compared directly to the results obtained by Cushley and Noël () in their study for ADS‐B signals.…”

“…In Cushley () several different grid sizes ( ) were tested. For all the results in Cushley and Noël () a grid of 100 100 pixels having intervals of 10 km in altitude and 0.25° in latitude was selected. The depth of the pixels (or voxels) in the grid , or the longitudinal extent over which data were simulated and for which the 2‐D reconstruction was representative of the electron density was chosen to be 1° (i.e., the electron density was assumed to be uniform over a 1° slice of longitude).…”

Extremely low frequency band station for natural electromagnetic noise measurement

“…Some recent stations concerning SR measurements are reported in Zhou et al [2013], Kulak et al [2014], and Sierra et al [2014]. From a more general point of view, not only concerning measurement stations, the interest in the study of the global and local ionosphere electromagnetic properties and applications becomes evident from the number and diversity of recent papers concerning these topics [Cushley and Noël, 2014;Gulyaeva et al, 2014;Cherniak et al, 2014;Nickolaenko and Hayakawa, 2014;Ohta et al, 2013;Fraser-Smith and Kjono, 2014].…”