The Deep Space Network (DSN) Array of the future provides an intriguing possibility of using the techniques of in-beam phase referencing to determine the angular position of spacecraft with accuracy at the level of 0.1 nano-radian (nrad). In this paper, we discuss the prospects for carrying out such measurements at both 8.4 GHz (X-band) and 32 GHz (Ka-band). Our study suggests that at X-band in-beam calibration may be available as an astrometric tool over 20-30 percent of the sky. The prospects at Ka-band, on the other hand, are not very hopeful. We point out that these estimates depend strongly on the number density of compact sources at the 1-mJy level. We also present the results from our recent VLBA (Very Long Baseline Array) observations at X-band, which has determined the compact source density at the 10-mJy level and discuss future observations to probe weaker source population. Finally, we discuss issues related to phase cycle ambiguity resolution and potential techniques to resolve them.
Precision Spacecraft Tracking Using In-Beam Phase Referencing
2008-03-01
996247 byte
Aufsatz (Konferenz)
Elektronische Ressource
Englisch
Online Contents | 2011
|Precision Sun Tracking Sensor for Spacecraft GN&C
British Library Conference Proceedings | 1995
|Demonstration of KVN phase referencing capability
Online Contents | 2015
|Demonstration of KVN phase referencing capability
Elsevier | 2015
|