@conference {172, title = {Analysis of the August 2017 Eclipse{\textquoteright}s Effect on Radio Wave Propagation Employing a Raytrace Algorithm}, booktitle = {NSF CEDAR (Coupling, Energetics, and Dynamics of Atmospheric Regions)}, year = {2017}, month = {06/2017}, address = {Keystone, CO}, abstract = {

The upcoming total solar eclipse over the continental United States on August 21 offers an unique opportunity to study the dependence of the ionospheric density and morphology on incident solar radiation. There are significant differences between the conditions during a solar eclipse and the conditions normally experienced at sunset and sunrise, including the west-to-east motion of the eclipse terminator, the duration of the event, the solar zenith angle, and the continued visibility of the corona. Taken together, these factors imply that unique ionospheric responses may be witnessed during eclipses, as measured by changes in radio frequency (RF) propagation. High Frequency (HF) propagation varies greatly depending on ionospheric conditions. Hence, our analysis will include data collected during the eclipse by several HF systems shown in Figure 1 including SuperDARN, temporary radio transceiver sites, and amateur radio networks such as the Reverse Beacon Network (RBN) and Weak Signal Propagation Reporter Network (WSPRNet). The data analysis will be guided by raytrace models of HF propagation through an eclipsed ionosphere employing the HF propagation toolbox, PHaRLAP (created by Dr. Manuel Cervera).

}, author = {M. L. Moses and S. Burujupali and K. Brosie and S. Dixit and G. D. Earle and L. Kordella and N. A. Frissell and C. Chitale} } @conference {144, title = {Characterizing the Ionosphere Using a Commercial Off the Shelf Software Defined Radio System}, booktitle = {Fall 2016 American Geophysical Union}, year = {2016}, month = {12/2016}, publisher = {American Geophysical Union}, organization = {American Geophysical Union}, address = {San Francsico}, abstract = {

On August 21, 2017, there will be a total solar eclipse over the continental United States (US). Solar eclipses offer a way to study the dependence of the ionospheric density and morphology on incident solar radiation. There are significant differences between the conditions during a solar eclipse and the conditions normally experienced at sunset and sunrise, including the east-west motion of the eclipse terminator, the speed of the transition, and the continued visibility of the corona throughout the eclipse interval. Taken together, these factors imply that unique ionospheric responses may be witnessed during eclipses including variations in the density and altitude of the F2 peak. In order to study these changes, we will establish four temporary field stations along the path of totality to track the maximum usable frequency (MUF) across the US over the course of the eclipse. Each field station shall consist of a commercial off the shelf (COTS) software defined radio (SDR) transceiver, a laptop computer running automatic link establishment (ALE) software, a Global Positioning System (GPS) receiver for timing, and a COTS antenna. Custom ALE software will automate the sites{\textquoteright} operation during the experiment to determine the MUF. As a validation test prior to the eclipse, we established three sites along the east coast to confirm that the SDRs are capable of inferring ionospheric conditions. The preliminary results characterize the effects of the sunrise/sunset terminator on our system{\textquoteright}s measurements as well as the change in foF2 during different seasons and under different geomagnetic conditions.

}, url = {http://hamsci.org/sites/default/files/publications/2016_AGU_Moses.pdf}, author = {Magdalina L. Moses and S. Dixit and Gregory D. Earle and Nathaniel A. Frissell and Lee Kordella and Xiaoyu Han and Charudatta Chitale} }