The objective of the GHOST project is to design, develop and validate a novel on-ground measurement instrument prototype for satellite In-Orbit-Test. The so called In-Orbit-Test (IOT) operation of the satellite payload consists in transmitting and receiving to and from the satellite a specifically designed test signal, mainly a spread spectrum signal, for the measurement and extraction of some key payload parameters such as, on-board filters responses, high power amplifier response, G/T, etc.. The IOT operation is fundamental in several situations during the life-time of the satellite to verify and monitor the performance and functional requirements of the satellite payload.
This project has two main challenges:
- Hardware/firmware/software implementation of the measurement algorithms
- Digital and analogue design and implementation to meet the stringent performance (including bandwidth) and accuracy requirements
The benefits of this product are:
- It allows customers to continuously monitor the satellite transponder payload status during operation and re-location phases. This includes the determination of parameters that affect the end-customers delivered quality of service, such as the on-board filters and power amplifiers characteristics.
- The possibility of performing non-interfering tests in “close or open loop” modes, enabling the utilization of the equipment in a distributed scenario.
- Its capability to do measurements, enabling the application of the product to all the emerging wideband satellite transponders
he capabilities of the product are:
- During “On-station” phase and in presence of traffic, measure the transponder characteristics under load.
- During “Drift”, “Re-location” and IOT, avoiding to interfere with adjacent/nearby satellites.
- Anomaly investigation of the payload hardware such as a sudden degradation of the delivered quality of service.
- On Occasional use or regular basis, the customer could be interested in monitoring the payload status, and the corresponding ageing effects.
The technologies that support these capabilities are:
- Design, development and validation of a powerful, flexible and wide-bandwidth technological platform incorporating an adaptable analog interface and a fully re-configurable SDR digital processing part.
- The definition of novel test measurement methods based on spread spectrum technology. This includes novel techniques to monitor the on-board HPA characteristic and to identify possible degradation effects.
- The definition of novel algorithms and methods to reduce testing time and improve accuracy for the existing measurements methods applied to wideband applications.
The selected underlying hardware architecture is based on the concept of Software Defined Radio (SDR), including a reconfigurable digital design platform that uses components such as state of the art DSPs and FPGAs.
From a high level prospective, for the hardware system architecture, a modular concept has been chosen due to its flexibility, scalability, maintainability and upgradability. It consists on splitting the GHOST system in two independent modules (or boards). All “Transmitters”, “Receivers” and “Controller” boards communicate with each other and with other external peripherals via a logical bus.
The software architecture includes the two main components “embedded system software” and “IOT bench controller software”.
The commercialization of the GHOST system as a product is achieved in two phases. The Phase I, covered by this project, it is aimed at designing a novel and competitive non-intrusive IOT system and at implementing and validating it as a pre-production prototype. This is achieved by sequentially completing the following tasks and milestones:
- Technology Selection and Architecture Definition
- incl. Requirements Definition and Simulations
- System Design
- System Implementation & Test
- Assembly, Integration and Validation
Subsequently, the product development and commercialization will be achieved with Phase II (out of scope of this project).
In line with schedule, the Baseline Design Review (BDR) has been passed successfully in July 2017 and concluded with a set of documentation deliverables, amongst others the Requirements Document, Measurement Algorithms Document, Simulation Results as well as the Design & Architecture Document.
Following the BDR, the System Design work packages have been kicked off to conclude with a planned CDR in November 2017.