Accession Number : ADA257771


Title :   Investigation of Frequency Diversity Effects on Meteor Scatter Links.


Descriptive Note : Interim rept.,


Corporate Author : PHILLIPS LAB HANSCOM AFB MA


Personal Author(s) : Ostergaard, J C ; Bailey, A D ; Li, S W


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a257771.pdf


Report Date : 09 Jan 1991


Pagination or Media Count : 25


Abstract : Results of measurements of frequency diversity effects on the USAF geophysics Laboratory 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.


Descriptors :   *RADIO LINKS , FREQUENCY , PROPAGATION , HIGH FREQUENCY , LOW FREQUENCY , GREENLAND , FREQUENCY DIVERSITY , ATMOSPHERIC DENSITY , MORPHOLOGY , SIGNALS , HIGH ALTITUDE


Subject Categories : Radio Communications


Distribution Statement : APPROVED FOR PUBLIC RELEASE