Radio-meteor investigations of atmospheric motion
Degree GrantorUniversity of Canterbury
Degree NameDoctor of Philosophy
A coherent pulse radar has been addressed to the problem of tracking drifting meteor trains to deduce neutral atmosphere velocities in the height range 80 to 110 km. The present work describes the principles of operation, the implementation of these principles and the calibration of such a meteor radar. The doppler frequency shift or equivalent phase changes of the reflected signal are considered to be due to a radial movement of the ionized column. The theory of radio wave reflections from meteor trains is considered in detail, with particular regard to the interpretation of the received signal phase changes as being due to radial movements. It is shown that spurious radial velocities can arise from echoes from meteor trains with electron line densities in excess of 10 ¹⁴m⁻¹ Amplitude characteristics including echo decays and polarization phenomena are also considered. Results are presented from a nine day observing period in July 1977. The wind velocity results reveal the dominance of a regular semi-diurnal tidal component, the irregularity of the diurnal component and the existence of longer period (70 to 80 hours) oscillations at meteor heights.