2011 SuperDARN Workshop
The radio wave power distribution at HF frequencies as modelled for Radio Receiver Instrument (RRI) investigations on th ePOP satellite mission
R.G. Gillies (1), G.C. Hussey (1), G.J. Sofko (1), H.G. James (2)
(1) University of Saskatchewan, Saskatoon, Canada
(2) Communications Research Centre Canada, Ottawa, Canada
abstract. The Cascade Demonstrator Small-Sat and Ionospheric Polar Explorer (CASSIOPE) satellite is scheduled to be launched as early as December 2011. The scientific payload on this satellite will consist of a suite of eight scientific instruments comprising the enhanced Polar Outflow Probe (ePOP). One instrument, the Radio Receiver Instrument (RRI), will be used to receive HF transmissions from ground transmitters such as SuperDARN. Magnetoionic polarization and propagation theory has been used to model the relative power that SuperDARN will deliver to the Ordinary (O) and Extraordinary (X) modes of propagation, with reference to the RRI/ePOP orbit. The geometry of the ground-based radars and the Earth's magnetic field results in the X-mode dominating the transmitted signal when a radar wave propagates northward, where it is nearly perpendicular to the geomagnetic field lines. Other propagation directions (i.e., above or southwards of the radar) results in propagation whic h is anti-parallel to the geomagnetic field lines and an equal splitting of transmitted power between the O- and X-modes occurs. For either high transmitting frequencies or low ionospheric electron densities, the range of latitudes that signal will be received at the satellite is significant (up to ~90 degrees of latitude). Conversely, for lower transmitting frequencies or higher ionospheric electron densities, the latitudinal range that signal will be received by the RRI is smaller. This modelling work will be used as a basis for interpretation of the signal received by the RRI when the ePOP satellite is operational.