The satellite communications and ground segment industries are at a critical stage of development as market needs change. The main driver for advancement comes from increased customer demand. Customers would like greater flexibility and autonomy in the services they can use, and simultaneously there is an increased demand for over-the-top (OTT) media services (such as subscription-based video on demand) and a need to transfer the large amount of data collected by the satellites.
This creates challenges and opportunities for satellite operators and manufacturers. Dr Siegbert Martin, CTO and Head of Development and Design at Tesat Spacecom, a payload equipment developer for satellites, highlights this: “The main challenge is driven by market demand. It means meeting cost targets so that satellite communication systems become a real opportunity and complement terrestrial data communication networks.”
Despite these growing market needs, Dr Martin reckons there is a larger opportunity for satellite communications. “I’m discovering a lack of awareness about space capability among network suppliers and in the public in many conversations. Satellite technology can close the gaps of data connectivity in rural areas and is part of realising the digital roadmap. Finally, with a view to satellites becoming part of the 5G network, a link between terrestrial operators and satellite network operators is essential and has to be built up.”
These increased market needs require satellite manufacturers and operators to develop systems and offer a variety of radio frequency bands, as well as lesser-used technologies, such as laser communication (also known as optical communication). There has been a rise in interest in optical communications over the last couple of years. The technology isn’t new but is at a point where it has become advanced and affordable enough to implement for satellite communications. This implementation may be the trickiest part of all. Katherine Monson, Head of KSAT USA, a ground-system operator, confirms this: “The challenge is in the implementation, not the technology. Much of the optical development so far has been applied in a scientific or proof-of-concept domain, so the challenge is now to operationalise the technology, to rollout out global locations, and to provide the service at a price point that remains attractive compared even with RF.”
There is also a requirement from customers to be more in control of their satellite operations, which is something Amazon Web Services aims to provide with its Ground Station As A Service, introduced earlier in 2019. Furthermore, there is a need for a wider and more flexible offering of capabilities from the ground segment, which Italian startup Leaf Space aims to offer.
Another main point of discussion is the security of satellite signals. Various countries across the globe, including the UK, have expressed concern regarding increasing threats to satellite-based navigation, which has spurred a need for robust communication systems. The European Space Agency is also increasing efforts regarding safety and security for communications systems.
Monson is convinced that optical communications will play a vital role in providing signal security: “Personally, I think the biggest advantage of optical is the information security. With an incredibly small beam width (as compared with RF), it is almost impossible to ‘eavesdrop’ on an optical connection from outside the physical premises.”
Martin agrees with this: “For point-to-point high data connection, optical communication is the most efficient technology considering mass, power and cost. Due to the narrow optical beam, we have no interference with other systems.” He also outlines the technical capabilities of optical communications: “We currently see three main applications: optical inter-satellite communication in LEO or GEO constellations, optical feeder links for data up- or download, and quantum key distribution to secure data communication. Related to communication satellites, the push and speed of technology implementation are correlated to the increase in router and digital multiplexing capability in space.”
At the same time there has been an ongoing discussion about spectrum allocation. Monson: “We have had many conversations with the ITU satellite regulations team about this very question. One of the challenges is that our current regulatory regime is based on assigning frequency bands to usage, so that Earth observation and telecommunications are assigned to different bands. That makes it challenging to provide a cost-effective service to all users of the satellite spectrum, because there can be no economy-of-scale advantage if different frequencies (and therefore different antennas) are used. At this point, many missions leverage Earth observation spectrum allocation, by flying at least one Earth observation payload – though in the long run, I hope there is a move to rethink the spectrum allocation, so that operators do not have to jump over this hurdle.”
The market move to higher frequencies, such as Ka, W and optical, prompts questions around who is allocated what part of the spectrum and where the optical side of things fits in with spectrum allocation.
Keen to learn more about the developments regarding (inter)satellite communications? Join us at the Industry Conference at Space Tech Expo Europe 2019 on 19-21 November in Bremen, Germany.
The panel Improving and Securing (Inter)Satellite Communications: Finding a Balance Between Hardware and Software to Optimise Optical, Radio-Frequency and Ground Systems (taking place in the Industry Conference on Wednesday, 20 November) discusses several of the aforementioned challenges, with speakers from ESA/ESOC, Tesat Spacecom, Mynaric and KSAT.