1. CAP congress, Ottawa, June 13-17, 2016
Monitoring HF transmissions with the e-POP RRI instrument on the CASSIOPE Satellite Donald Danskin Natural Resources Canada
H.G. James
CAP congress, Ottawa, June 13-17, 2016

2. Introduction
NRCan operates a HF transmitter in Ottawa for monitoring the ionospheric propagation at the high latitudes.
The transmissions alternate between CW or Barker coded Binary Phase Shift Keying (BPSK) that introduces 180 phase shift at known intervals.
The transmissions can be received either on the ground or at satellites with HF receivers such as RRI on CASSIOPE.
Inverted V antenna with optimal signal at low elevation angles (omnidirectional).
RRI has crossed dipoles oriented toward Tx

3. Examples of HF transmission of BPSK
B2000  0.5 msec
I/Q receiver

4. Animation courtesy of A. Howarth, U of Calgary

5. Spectral plot of 4 minute pass
Tx operational mode
0.9 s tone
1.1 s off
7.0 s BPSK
1.0 s off
Repeat every 10 s
Start of BPSK and tone
GPS timed
Stop Tx
Start Tx
Frequency

6. Gillies, R. G. , G. C. Hussey, G. J. Sofko, and H. G
Gillies, R. G., G. C. Hussey, G. J. Sofko, and H. G. James (2012), Modeling measurements of ionospheric density structures using the polarization of high-frequency waves detected by the Radio Receiver Instrument on the enhanced Polar Outflow Probe, J. Geophys. Res., 117, A04316, doi: /2011JA
James, H. G., R. G. Gillies, G. C. Hussey, and P. Prikryl (2006), HF fades caused by multiple wave fronts detected by a dipole antenna in the ionosphere, Radio Sci., 41, RS4018, doi: /2005RS

7. Frequency shift ?
Doppler shift +
Difference in LO’s

8. BPSK pulse used to estimate propagation time
Prime axis
Orthogonal axis

9. Apparent propagation delay

10. Ionosonde data

11. Amplitude Fading

12. Gillies, R. G. , G. C. Hussey, H. G. James, G. J. Sofko, and D
Gillies, R. G., G. C. Hussey, H. G. James, G. J. Sofko, and D. André (2007), Modelling and observation of transionospheric propagation results from ISIS II in preparation for ePOP, Ann. Geophys., 25, 87–97.

13. Conclusion
Reception of transmissions of both tone and BPSK show the expected Doppler shift due to motion of the satellite and can used to characterize the difference in local oscillator frequencies
The lack of signal detected by RRI at low latitudes indicates that rays are bent back to Earth by the ionosphere
Excess time delay indicates that longer ray paths are taken due to ionospheric refraction. Sporadic E events cause a significant delay
Faraday rotation is observed with signal strength alternating between the orthogonal antenna
Fading rates are consistent with modelled theory up to ~3 Hz.