The track-level compensation technique is an open-loop control of the RF beam position. The beam position is calculated with respect to the antenna azimuth and elevation position from the look-up table, and the antenna position is corrected to reduce the pointing error.
The whole antenna structure rotates in azimuth on a circular azimuth track. It is manufactured with the level of precision of ±0.5 mm for the 34-m DSN antennas. For more discussion of the azimuth track design, see . The pointing accuracy of the antennas and radiotelescopes is impacted by the unevenness of the antenna azimuth track. The track unevenness causes repeated antenna tilts, hence repeatable pointing errors. In this chapter, track-level errors are described along with their compensation using the look-up table. Also, the creation of the table is described, which includes the collection and processing of the inclinometer data, and determining azimuth axis tilt. Next, the antenna pointing errors are derived...
KeywordsBeam Position Elevation Correction Elevation Error Radio Beam Track Profile
- 1.Antebi J, Kan FW. (2003) Precision Continuous High-Strength Azimuth Track gor Large Telescopes. Proc. of SPIE, Future Giant Telescopes, 4840: 612–623.Google Scholar
- 2.Gawronski W, Baher F, Quintero O. (2000). Azimuth track-level Compensation to Reduce Blind Pointing Errors of the Deep Space Network Antennas. IEEE Antennas and Propagation Magazine, vol. 42.Google Scholar
- 3.Gawronski W, Baher F, Gama E. (2006). Track-Level Compensation Look-Up Table Improves Antenna Pointing Precision. IPN Progress Report 42–164. Available at http://ipnpr.jpl.nasa.gov/progress_report/42-164/164E.pdf
- 4.Greve M, Bremer J, Penalver P, et al. (2005). Improvement of the IRAM 30-m Telescope from Temperature Measurements and Finite-Element Calculations. IEEE Trans. Antennas and Propagation, 53(2).Google Scholar
- 5.Pisanu T, Morisani M, Pernechele C, et al. (2004). How to Improve the High-Frequency Capabilities of SRT. Proc. 7th European VLBI Network Symposium, Toledo, Spain, 2004.Google Scholar