HF Radio Wave Propagation in the Ionosphere Observed with the ePOP RRI (Radio Receiver Instrument) -- SuperDARN Experiment

The Radio Receiver Instrument (RRI) on the enhanced Polar Outflow Probe (ePOP) scientific payload of the recently launched CSA (Canadian Space Agency) CASSIOPE (Cascade Demonstrator Small-Sat and Ionospheric Polar Explorer) satellite mission and the Super Dual Auroral Radar Network (SuperDARN) of HF radars have successfully executed a number of experiments since the launch of ePOP in late September, 2013. This presentation investigates the propagation delays and timing associated with HF radio waves transversing the plasma in the terrestrial ionosphere. Both the relative and absolute timing of the co-ordinated SuperDARN-RRI experiments will be presented. This knowledge is essential for interpreting HF radio wave propagation effects such as range accuracy, mode-splitting and timing, Doppler shift, and delayed 'echo' signatures, for example.