Citation
Abstract
The deviations of the azimuth track level of a beam-waveguide (BWG) antenna shall not exceed ±0.5 mm. During tracking, this amplitude of deviations causes deformations of antenna structure, resulting in pointing errors that exceed the required accuracy for 32-GHz (Ka-band) tracking. However, structural deformations caused by the azimuth-track unevenness are repeatable; therefore, a look-up table can be created to improve the blind-pointing accuracy. This article presents the process for creation of the look-up table, describes the instrumentation (inclinometers and data-collection system) necessary for determining the pointing errors, and describes the processing of inclinometer data. It derives algorithms for the pointing-error estimation and for the azimuth-axis tilt using the inclinometer data. It compares the error corrections based on the created look-up table and actual measurements of pointing errors using the conical scanning (CONSCAN) technique. This comparison shows a satisfactory convergence that justiffes the implementation of the approach in the forthcoming NASA missions.
Keywords
Details
- Volume
- 42-139
- Published
- November 15, 1999
- Pages
- 1–18
- File Size
- 1.7 MB