South American flight test report

A flight test was conducted into the equatorial region to investigate UHF ionospheric scintillation fading. The test involved the Avionics Laboratory SATCOM-equipped aircraft and the Air Force Geophysics Laboratory flying ionospheric laboratory. Equatorial UHF ionospheric scintillation fading was encountered approximately 25% of test period. A multipath fading mitigation technique was tested which utilizes signals received on bottom and top mounted antennas to reduce the fading effect. The ASC-28 Dual Frequency SATCOM terminal was evaluated during the test flights. The performance of the EHF and SHF antennas during zenith operation was successfully demonstrated. The ASC-31 1 kw UHF power amplifier was tested using the ARC-171 UHF transceiver as a driving source.