ECSS-E-50-02A – Ranging and Doppler tracking (24 November 2005)

This standard has been cancelled and replaced by ECSS-E-ST-50-02C (31 July 2008).


This Standard is applicable to spacecraft that are supported for ranging or Doppler tracking by direct links to Earth stations 1 and to all related Earth stations operating within the Space Operation, Space Research and Earth Exploration Satellite services 2 as defined in ECSS-E-50-05A Clause 1.

Other space telecommunication services are not covered in this issue.

This Standard applies to projects with unprocessed ranging accuracies 3 of 2,5ns to 30 ns and Doppler tracking accuracies of 0,1 mm/s to 1 mm/s. The analysis of compatibility between systems compliant with this standard and with the CCSDS recommendations is given in Annexes A.2 and A.3.

This document:

  • Defines the requirements concerning spacecraft transponder and Earth station equipment for the purposes of ranging and Doppler tracking.
  • Provides criteria by which the extent to which the accuracy4 of the measurements is influenced by equipment effects can be determined.

When viewed from the perspective of a specific project context, the requirements defined in this standard should be tailored to match the genuine requirements of a particular profile and circumstances of a project.

NOTE: Tailoring is a process by which individual requirements or specifications, standards and related documents are evaluated and made applicable to a specific project, by selection and, in some exceptional cases, modifications of existing or addition of new requirements.

1 Therefore, this Standard is not applicable for spacecraft supported by data relay satellites.
2 Therefore, this Standard is not applicable to the Meteorological Satellite service.
3 For conventional projects with tracking accuracies less stringent than these, CCSDS 401.0-B recommendations may be sufficient.
4 This accuracy is different to the accuracy of the overall orbit determination process, which is also influenced by effects outside the scope of the standards, i.e. modelling of gravitational and non-gravitational forces, modelling of propagation effects, pre-processing and screening of data.