Galileo Technology Developments
Galileo is an initiative of the European Space Agency (ESA) and the European Commission (EC). GalileoSat is the name given to the complementary development programme being carried out by ESA.
The various developments are described below:
Clock Monitoring and Control Unit (CMCU) interfaces the onboard Atomic Frequency Standards.
Galileo Communications Network provides integrity flags which indicate the quality of the Galileo navigation signals.
Comparative Study on Software Development Environments and Implementation Technologies identifies the key properties of software components for the Galileo Ground Segment and the best technologies to implement these components.
Galileo Constellation Mission Control System (GMCS) Assessment investigates whether there is a suitable European Mission Control System (MCS) platform that can be used as the basis for the GMCS.
Galileo System Simulation Facility (GSSF) is a software simulation tool that reproduces the functional and performance behaviour of the Galileo system.
Galileo System Test Bed Version 1 (GSTB-V1) reduces the risk on the Galileo ground segment development through early experimentation with the Orbit Determination & Time Synchronisation and Integrity techniques.
A Ground Segment Data Model & Data Standard (GMXL) has been developed for the full Galileo Ground segment to ensure consistency, commonality and good operability between Ground Segment subsystems. This investigates the use of extensible mark up language (XML) and involves the development of software to convert navigation receiver data into the XML format.
Galileo Interference Measurement Campaign investigates how well Galileo receivers can operate in the presence of interference.
Navigation Signal Generation Unit (NSGU) now under development generates the truly precise signals that convey accurate satellite time and ephemeris required for Galileo.
The Passive Hydrogen Maser (PHM) with its excellent frequency stability performance has been chosen as the Master clock in the Galileo Navigation Payload.
The Rubidium Atomic Frequency Standard (RAFS) is today the most widely used clock. The RAFS is currently one of the two clock technologies that is to be used in the Galileo Navigation Payload.
Galileo Receiver Pre-Developments investigates the most critical User Receivers and Ground Reference Receivers issues.
The Galileo Solid State Power Amplifier (SSPA) onboard Galileo needs to generate four signals (carriers) in two different frequency bands. The output power for each individual signal is more than 50 Watts. Obtaining the required output power levels with a certain efficiency and within preset linearity requirements proves to be a key requirement for the optimisation of the payload and indeed, the Galileo satellites.
Dual Mode TT&C Transponder unit performs the following functions in both standard and spread spectrum mode: Up-link telecommand demodulation, Down-link telemetry transmission, Coherent frequency turn-around and Ranging turn-around function.
