Hostname: page-component-7479d7b7d-rvbq7 Total loading time: 0 Render date: 2024-07-13T22:41:02.732Z Has data issue: false hasContentIssue false
  • English
  • Français

External Ground Monitoring v. Receiver Monitoring

Published online by Cambridge University Press:  21 October 2009

R. Johannessen
R. Johannessen
Affiliation:
(STC Technology Ltd)
Get access Rights & Permissions [Opens in a new window]

Extract

The transmissions from GPS and GLONASS navigation satellites include information about the state of those transmissions as perceived by the control centre. In the case of GPS, for example, this information is contained in the data stream in Subframe 1 Word 3. However, with some of the failure conditions that can arise there is a delay of the order of half an hour before this message is altered to signal that a failure exists. A situation can therefore arise when the satellite signals that all is well, whereas in fact it is not. The very high levels of integrity which civil aviation require before satellite navigation can be used with confidence therefore means that the warning messages from the satellite must be augmented by some other form of monitoring. Two alternatives exist: (1) to have a monitor at some fixed and surveyed ground location which broadcasts a warning to the navigating aircraft when there is a malfunction (ground monitoring), or (2) to arrange for the navigating receiver to perform its own internal monitoring, known as receiver autonomous integrity monitoring (RAIM). Each alternative is beneficial in its own way.

Keywords

1. Air navigation.2. Satellites.
Type
Research Article
Information
The Journal of Navigation , Volume 44 , Issue 1 , January 1991 , pp. 11 - 24
Copyright
Copyright © The Royal Institute of Navigation 1991

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

1Green, G. B., Massatt, P. D.and Rhodus, N. W. (1988). The GPS 21 primary satellite constellation. ION GPS-88, Colorado Springs.Google Scholar
2 Minimum operational performance specification for Navstar GPS aircraft receiving equipment.(1990). EUROCAE WG-28. Ninth draft, March.Google Scholar
3Johannessen, R. (1989).Coverage, satellite visibility and the likely error distribution for GPS in Europe.Proc. NAV 89.The Royal Institute of Navigation, London, October 17–19.Google Scholar
4 FANS/3-WP/111 Appendix J to the Report on Agenda Item 5, page 55–6.Google Scholar
5Kremer, G. T. et al.(1989). The effect of selective availability on differential GPS corrections. Paper to ION GPS-89, Colorado Springs, September 27–29.Google Scholar
6 System Specification for the Navstar Global Positioning System.(1987). SS-GPS-300C-001.Google Scholar
7Johannessen, R. and Asbury, M. J. A. (1990). Towards a quantitative assessment of benefits which INS/GPS integration can offer to civil aviation operating in a non-jamming environment.(1990). A paper to ION, San Diego, January 23–25.Google Scholar
8Ashway, M. J. A. et al.(1990). Probability distributions that are important when assessing barometric aiding to CGP. Proc ION CGS-90.Google Scholar
9US Federal Radionavigation Plan(1988).Google Scholar
10ICAO(1990)FANS(11)/1-WP/61. Montreal 22.05-08.06, 1990.Google Scholar