ČSN EN 16603-50-02

This Standard is applicable to spacecraft that are supported for ranging or Dop-pler tracking by direct links to Earth stations and to all related Earth stations (therefore, this Standard is not applicable for spacecraft supported by data relay satellites) operating within the Space Operation, Space Research and Earth Exploration Satellite services (therefore, this Standard is not applicable to the Meteorological Satellite service) as defined in ECSS-E-ST-50-05 clause 1. Other space telecommunication services are not covered in this issue. This Standard applies to projects with unprocessed ranging accuracies of 2,5ns to 30 ns (for conventional projects with tracking accuracies less stringent than these, CCSDS 401.0-B recommendations may be sufficient) 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: o Defines the requirements concerning spacecraft transponder and Earth station equipment for the purposes of ranging and Doppler tracking. o Provides criteria by which the extent to which the accuracy of the measurements is influenced by equipment effects can be determined. 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. This standard may be tailored for the specific characteristics and constraints of a space project in conformance with ECSS-S-ST-00.