M. E. Johnson and G. D. Gierhart

Abstract: This report provides extensive comparisons of measured propagation data with predictions made by the IF-77 (ITS-FAA-77) and other propagation models. Although IF-77 was developed for aeronautical applications, it can be used for some point-to-point propagation paths, and the measured data selected for comparison includes point-to-point as well as aeronautical paths. Approximately 870,000 hours of data are associated with the 242 paths used. Predictions made with IF-77 were always best or second best and were substantially better than those made for free space conditions. The IF-77 model has a wide range of application and provides predictions compatible with the more specialized models tested. A discussion of the aeronautical propagation data pool from which the data were selected is included as an appendix.

Keywords: interference; computer program; air-to-ground propagation; propagation model; transmission loss; air/air; DME; earth/satellite; EMC; frequency sharing; Instrument Landing System (ILS); navigation aids; Tactical Air Navigation (TACAN); VHF Omnirange (VOR)

Disclaimer: Certain commercial equipment, components, and software may be identified in this report to specify adequately the technical aspects of the reported results. In no case does such identification imply recommendation or endorsement by the National Telecommunications and Information Administration, nor does it imply that the equipment or software identified is necessarily the best available for the particular application or uses.

For questions or information on this or any other NTIA scientific publication, contact the ITS Publications Office at ITSinfo@ntia.gov or 303-497-3572.

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