Observations of the signal strength of HF signals propagated over high latitude paths

The high latitude ionosphere is a highly dynamic and disturbed medium which can severely affect high frequency (HF) radio signals propagating through these regions. In order to investigate this type of propagation, a frequency agile transmitter has been installed well within the Polar Cap at Clyde River, NWT, Canada (70 degrees N, 69 degrees W). Five receiving and data logging systems have been deployed to provide four trans-auroral oval paths and one path contained entirely within the Polar Cap region. Variations observed in the measured signal strength at each of the receiving sites during two one-month experimental campaigns undertaken at different times of year have been investigated and the results outlined.< >