IMPACT OF SATELLITE AERONAUTICAL CHANNEL ON MODEM SPECIFICATIONS. PHASE II. OCEANIC MULTIPATH MEASUREMENTS AND MODEM CONCEPTS

Abstract : The report completes the analysis initiated in the Phase I report of the effects of oceanic multipath on ranging and data modems for satellite air traffic control systems. The interaction between multipath antenna and apparent measured multipath is determined using a 'vector Kirchoff' model of ocean scattering. Procedures for antenna design, sea state sensing, and multipath measurements are detailed, and tone ranging performance is computed for various antenna designs. Consideration is given to the problem of tone probing on a 50 KHz hard limiting AEROSAT channel while data transmission is taking place. The problem of how much measurement time is needed to achieve a reliable measurement of error probability in data transmission over the AEROSAT channel is addressed.