Tropospheric Refractivity Profiles Inferred from RF Measurements-Passive Refractive Index by Satellite Monitoring (PRISM)

摘要

The objective of this work was to develop and validate a technique for passively inferring the tropospheric refractivity structure from observations of low-angle, satellite-to-ground rf transmissions. Eleven measurements of dual-frequency radio transmissions were made. The ducting structure was correctly inferred in seven of the lower frequency and five of the high-frequency observations. The inferred profile structure can differ significantly from the observed refractive structure. The major limitation to the applicability of this technique is an uncorrectable rms range error of about 4 km. These errors are caused by small-scale refractivity fluctuations in the atmosphere. Although moderate success was achieved in inferring the refractive structure from rf measurements, it is recommended that this project be terminated, since operationally significant data cannot be extracted reliably. (Author)