SSC Space UK is looking to evolve the ground network technologies and deliver a solution that addresses the bottlenecks that the NewSpace market sector is currently facing. There are three fundamental technologies that will be developed to address the spectrum limitations, the costs of network operations and the cost of spacecraft/constellation operations.
Beam forming array antennas – Array antennas with beam forming capabilities able to track and communicate with multiple spacecraft simultaneously.
Link Computer – A spacecraft subsystem that becomes a node in the network and manages all aspects of communications for the spacecraft.
Automated Spacecraft Operations – Operations Software that takes advantage of the functionality in the ink computer and the smart network, to deliver fully automated link negotiation and scheduling, as well as, management of spacecraft functional and flight health parameters.
The Overall communication system design, exploits advances in terrestrial communications and applies them within the space communications environment to achieve a significantly more efficient sharing of spectrum that, in many cases, leads to relaxation of the process of applying for an ITU license.
One of the major challenges of this programme is the management of the regulatory conditions and the need to review them so that they don’t impede the development and future use of the next generation network.
An additional technical challenge is the ability to make the system compatible with existing spacecraft communications systems without interfering, whilst also being able to serve a diverse range of spacecraft, including cubesats and the limitations they introduce in terms of power, mass and volume.
Finally, one of the fundamental aims of this programme is to develop a disruptive solution that leapfrogs existing communications technologies and causes a market shift towards a more harmonious and efficient use of the spectrum. This necessitates a significant adoption of the system so one of the challenges is to offer an attractive enough technology that enables this shift at the shortest possible timeframe.
Some of the main product benefits are:
More efficient use of spectrum – Through the development of a system that utilizes techniques developed for the terrestrial mobile communications systems. Those are robust, tested solutions that are capable of serving large numbers of users through better sharing of the spectrum.
Robust spacecraft communications with automated link management – The Link Computer offers an advanced architecture that connects the spacecraft seamlessly to the network and manages all aspects of negotiations and link establishment with the network.
Significantly lower cost ground segment solution – The introduction of electronically steerable beam forming antennas, enables simultaneous communications with multiple spacecraft whilst it significantly reduces the installation and maintenance costs of the system. As a result, the end user benefits from cost improvements through the sharing of the antenna but also through the reduced operational costs.
Constellation optimized architecture – With the introduction of the advanced communications system that encompasses the use of the link computer and the beam forming antennas, it is possible to maximise the benefits of those technologies by automating the link/network connection and the management of the functional parameters of the spacecraft. The spacecraft operations management system will monitor and maintain the platform health with minimum human intervention. This brings an additional layer of benefits to constellation operators by helping them to manage the spacecraft parameters with significantly reduced manpower.
The Ground Segment comprises a number of ground stations linked by network to a Global Network Operations Centre (GNOC).
Each ground station comprises:
- Electronically Steerable Phased Array (ESPA) antenna,
- Radio transceivers, (which may be integrated with the antenna and/or Modems)
- A local data server that provides low latency caching of data during the passes.
- A Ground station computer that controls the equipment and interfaces with the network.
The Space Segment, which is integrated with the spacecraft’s avionics, comprises:
- An antenna system – this may be a phased array or a simple antenna depending upon the characteristics and needs of the mission.
- Radio transceiver
- Link Computer. The link computer is the key element in the space segment. It manages all communications operations for the spacecraft and interfaces to the OBC and/or the Data Handling Unit.
The radio is tightly coupled to the Link Computer. The Link Computer will also support the GNSS and time management functions for the spacecraft if required.
The project is being developed over a number of phases. The first phase is the definition phase and is being delivered over a period of 12 months with a targeted completion of May 2021. The first major milestone evaluates the market requirements and the regulatory conditions with the aim of supporting some of the important system decisions for the development of the system components. The second milestone is planned for February 2021 and targets the review of the specifications of some of the major components of the overall system. The final milestone of the definition phase is scheduled for May 2021 and targets the review of all parameters of the system, in preparation for the development phase of the programme.
The programme has successfully Kicked off and in progressing in line with the initial planning towards the first major milestone. A business plan update that takes into account the effects of the global pandemic is in progress, together with the review of the regulatory conditions for implementing the GNNetE system.