VGSE - Versatile Ground Segment Equipment for End-to-End System Validation and Optimisation

Objectives

The objective of the activity is to develop flexible, modular and transportable ground segment equipment in the form of a prototype test-bed that can accurately characterise the performance of satellite communication systems and jointly optimise the payload and ground segment components in a variety of representative system scenarios and different air interfaces while one or several payload components are under test.

Challenges

The main challenge of the VGSE definitely is the generation of the broadband DVB signal of up to 500 MHz. Such a signal implies a data rate of more than two gigabyte per second which needs to be dealt with in both transmitting and receiving direction. Having a replay and recording capacity of up to one hour this data cannot be processed on standard platforms. A combination of CPUs, GPUs, FPGAs and server hosting is able to reduce the processing to a reasonable time.

Benefits

We expect one major benefit to be the relaxation of the RF requirements towards traffic throughput requirements. Currently the industry invests a lot of development meeting high safety margins; in relaxing them, we therefore expect a reduction in actual costs and time for the development, integration and end-to-end tests.
The continuous DVB streaming and analysis possibility together with the wide-band signals are unprecedented. This makes it a unique chance also for research activities.

With the VGSE the satellite operators, integrators and manufacturers will be able to verify and test their very expensive hardware based on real traffic data thus assuring their confidence in the equipment bought.

Features

The VGSE is a generic flexible wide-band waveform and traffic generator/analyser for end-to-end system validation and optimisation. The VGSE supports CW, modulated only and DVBS2/RCS(2) carriers  for a bandwidths of up to 500MHz.
 
Real-time signal generation and analysis is possible with a limited bandwidth depending on the processing power.
The VGSE is intended for all actors in the satellite industry value chain: space equipment manufacturers, payload/satellite integrators, satellite system operators and ground segment manufacturers;
 
The VGSE is build from the following components: The Monitoring & Control Unit represents the main interface to the operator. It does provide a user-friendly way of controlling the DVB signal generation, displaying the VGSE state and the accumulated results.
 
The DVB-S2/RCS(2) signals are calculated in the TX Processing Unit with numerous adjusting possibilities like pilots, frames, roll-off etc. The hardware is either a pure CPU, GPU or FPGA solution or a heterogeneous mix of CPUs, GPUs, and FPGAs. To gain flexibility for future enhancements the unit follows a modular approach. For wideband signals the processing power might not be sufficient enough to provide real-time data, thus it must be stored in the Mass Storage for offline replay. The data stream is then further routed to the TX RF Platform which does the transformation from digital baseband to analogue RF.
The RF signal is passed through the DUT (Device Under Test) where it is naturally degraded. This degradation is the very interesting information which allows the operator to optimise the transmission setup. Such values are I&Q constellations, error vectors, frame and bit error rate and traffic throughput (list not exhaustive). After the RX RF Platform has done the analogue to digital conversion the data stream gets stored in the Mass Memory. The RX Processing Unit immediately starts with the data processing showing up the result on the display.

Plan

The project is split into two phases.
Phase one is mainly characterised by performing use-case analysis and trade-off analysis for various architecture details. Before PDR and CDR the project is in close relation with consulting satellite manufacturers, operators and integrators. After the acceptance of phase one the second phase is dedicated in manufacturing the VGSE.

Phase two is dedicated for the manufacturing of a full functional VGSE prototype.

Current status

The project is currently in phase one creating the use-cases and analysing the detailed system requirements. Different hardware and software architecture is evaluated and documented to trade-off costs, project complexity, development time and a maximum of flexibility.

Contacts

Status date

Wednesday, February 19, 2014 - 13:46