Investigation of Frequency Diversity Effects on Meteor Scatter Links

摘要

Results of measurements of frequency diversity effects on the USAF GeophysicsLaboratory meteor scatter bed test in Greenland are reported. The investigation included three field campaigns over two test links to acquire meteor scatter signal data and a series of a special purpose statistical analysis procedures were developed. Diversity effects have been evaluated for frequency separations between 0.3 and 4 MHz at path lengths of 1200 and 700 km. The morphology of the results are described. Dual close-spaced frequency diversity seems to offer a limited improvement of channel properties and no frequency separation dependence was found. The apparent lack of monotonic frequency dependence leaves questions as to physical causes of variability. It is speculated that day to day changes in the neutral atmospheric density, high altitude winds and sporadic E-layer ionization should be investigated as candidate mechanisms.