WP4: VLBI (Research and technological development)

Objectives

The objective of this WP is to provide the residuals of spacecraft tracking data with repect to an a priory given state vectors of the spacecraft usiong the European and Global VLBI network observations, data processing and analysis.

Description of work (possibly broken down into tasks), and role of participants

Task 4.1: Installation, verification and tests of the VLBI near-field theoretical delay calculation software (VTD-NF)

VTD-NF software, compilant with VLBI Consensus model for far field source observation and near field enabled, needs to be installed and verified. Interface between the VTD-NF and supplier of the a priory state vectors of the spacecraft has to be etablished and verified.

Task 4.2: Verification and tests of the on-purpose devoleped ultra-high spectral resolution coerrelator software for spacecraft VLBI correlation

Specialized spacecraft signal VLBI correlation software is under development at JIVE and other European radio astronomical institutes. It needs further improvements and verification tests with spacecraft observations.

Task 4.3: Scheduling and performing test VLBI observations of several existing spacecraft

Existing ESA/NASA planetary mission spacecraft will be observed using European and Global VLBI network radio telescopes in phase referencing mode in order to assess the potential accuracy of the spacecraft state vectores determination using the a priory state vectors as the input to VTD-NF for theoretical delay prediction and observed data processing using the broad band EVN Mk5 correlator at JIVE and spacecraft signal tuned software correlator.

Task 4.4: Post-correlation analysis of the broad-band far-field phase referencing radio sources (from ICRF and other catalogues) data and near-field narrow band spacecraft data

Post-correlation analysis is aimed to deliver the deviations of the measured state vectors of the spacecraft with respect to the a priori ones.

Task 4.5: Analysis of the results

Resulting state vectors will be available for other participants of the project for further in deppth analysis.

Task 4.6: Optimization of the observational, processing and analysis techniques, recommendations for further developments