Assessing the impact of E-region coherent backscatter on HF propagation at auroral latitudes with e-POP RRI measurements and ray trace modeling

Abstract:

A high frequency (HF) ray trace model was recently developed using the Provision of High-Frequency Raytracing Laboratory for Propagation Studies (PHaRLAP) toolbox to help interpret measurements of high frequency (HF) Super Dual Auroral Radar Network (SuperDARN) systems. The modeled predictions of emitted power at ionospheric altitudes concur with measurements provided by the Radio Receiver Instrument (RRI) onboard the Enhanced Polar Outflow Probe (e-POP) in conjunctions with SuperDARN Saskatoon, except when intense E-region backscatter is present in between the radar and RRI. Further evaluation shows that some E-region backscattering events are more deleterious to HF propagation conditions than others. Currently, the link between the nature of the backscatter and the transmitted signal power (beyond the scattering region) is not well understood. In this presentation, we will detail the new ray trace model and demonstrate its capacity to predict SuperDARN Saskatoon’s emitted power at ionospheric altitudes. Then, we will focus on RRI-Saskatoon conjunctions in which E-region coherent backscatter is present and report on the connection between the characteristics of the coherent backscatter signature (e.g., intensity, Doppler shift and spread) and the power received by RRI and its correspondence to the aforementioned ray trace model.