Shemya Tropospheric Refraction Errors,
Abstract
An attempt was made to characterize the Shemya, Alaska, troposphere to determine the tropospheric refraction errors in range and angle. Subsequently, various correction methods for these errors were investigated for a radar based at Shemya, Alaska, and operating at low elevation angles of 0 deg to 2.5 deg. The troposphere was characterized in terms of refractivity N profiles which were derived from airborne refractometer measurements made over a two-week period in June 1973. A cessna 310 mounted refractometer of the Vetter-Thompson type was used. The range and angle shifts and their standard deviations that the Shemya radar would experience due to this troposphere were determined by computer ray tracing through a spherically stratified troposphere. The average shifts varied from about 330 feet to 150 feet in range and from about 8 mr to 4 mr angle as the elevation angle increased from 0 deg to 2.5 deg and out to a 300 NM range. The corresponding standard deviations varied from about 10 feet to 7 feet in range and from about 1 mr to .2 mr in angle. Three correction methods are considered. The best correction method was found to be that based on the linear model.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1976
- Accession Number
- ADA030780
Entities
People
- Edward Malowicki
- Patrick R. Hoffman
Organizations
- Rome Laboratory