Hostname: page-component-77c89778f8-swr86 Total loading time: 0 Render date: 2024-07-17T10:06:37.155Z Has data issue: false hasContentIssue false
  • English
  • Français

Technique for Initialization and Synchronous Setting of Space Vehicle Time with Navigation System Time

Published online by Cambridge University Press:  25 November 2011

Parimal Majithiya ,
Kriti Khatri  and
J. K. Hota
Parimal Majithiya*
Affiliation:
(Space Applications Centre, Indian Space Research Organization, Ahmedabad, India)
Kriti Khatri
Affiliation:
(Space Applications Centre, Indian Space Research Organization, Ahmedabad, India)
J. K. Hota
Affiliation:
(Space Applications Centre, Indian Space Research Organization, Ahmedabad, India)
*
(E-mail: p_majithiya@sac.isro.gov.in)
Get access Rights & Permissions [Opens in a new window]

Abstract

Satellite Navigation Systems (SNS) provide Position, Velocity and Time (PVT) services. The SNS is required to maintain its own System Time with high accuracy. To set up the precise System Time, each system component should maintain its own time within a specified limit. In the SNS, the onboard Space Vehicle (SV) time generator is one of the components and it should be set and maintained with few nanoseconds accuracy. To achieve accurate time setting with minimum difference between the ground and onboard SV systems, the onboard time setting should be highly predictable and accurate. This paper proposes an approach to initialize/set the onboard SV Time. The paper also discusses the concept of synchronization of SV Time with System Time with an overall accuracy better than 1 nsec. The proposed technique requires minimum setting time and synchronization steps and there is no need to predict accurate uplink propagation delay and command execution time.

Keywords

NavigationSynchronizationPropagation
Type
Research Article
Information
The Journal of Navigation , Volume 65 , Issue 1 , January 2012 , pp. 159 - 168
Copyright
Copyright © The Royal Institute of Navigation 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Parkinson, B. W. and Spilker, J. J. Jr. (1994). Global Positioning System: Theory and Applications, Volume I. American Institute of Aeronautics and Astronautics, Inc.Google Scholar
U.S. Air Force. (2006). Interface Specification IS-GPS-200, Revision D, IRN-200D-001. U.S. Air Force GPS Directorate.Google Scholar
U.S. Air Force, (2007). IS-GPS-800, Navstar GPS Space Segment/User Segment L1C Interface. U.S. Air Force, GPS Directorate.Google Scholar
Majithiya, P., Kriti Khatri, K. and Hota, J. K. (2011). Indian Regional Navigation Satellite System: Correction parameters for Timing Group Delays. Inside GNSS, 40–46.Google Scholar
Mishra, Pratap and Enge, Per (2006). Global Positioning System, Signals, Measurements and Performance, Edition 2. Ganga-Jamuna Press.Google Scholar