Long history, bright future: Geostationary satellite innovation on the rise
At this timely moment came the third installment of ITU’s satellite webinar series, which have so far enjoyed an audience of over 1,500 participants from more than 120 countries, said ITU Radiocommunication Bureau Director Mario Maniewicz during his opening remarks.
The webinar focused on systems in the geostationary-satellite orbit (GSO), which refers to satellites that operate from 36,000 kilometres above the Earth, where they appear fixed in the sky when observed from the ground.
“GSOs have a long history from the first launch over the Atlantic in the 1960s for interoceanic telecommunication,” noted Mr. Maniewicz. “Today, they are reaching every single populated corner of the globe.”
GSO-relevant WRC-19 decisions
Nelson Malaguti, moderator and Counsellor from ITU Radiocommunication Sector (ITU-R) Study Group 4, reviewed two crucial decisions made during the 2019 World Radiocommunication Conference (WRC-19) related specifically to the technical and regulatory conditions under which GSO satellites can operate.
The first was the use of additional frequency bands for Earth stations in motion (ESIMs), which communicate with GSO satellites to connect moving platforms like vessels or planes typically beyond the reach of terrestrial networks, resulting in a total of “2.5 GHz in the downlink and in the uplink in all regions worldwide,” said Mr. Malaguti.
“This is a significant achievement if we look at the results of the last two WRCs,” he added.ESIMs contribute to Sustainable Development Goal 9 (Industry, Innovation and Infrastructure) by enabling broadband connection of people on ships, aircraft and land vehicles and ensuring their safety, security and comfort while on the move. This WRC-19 decision will increase the use and foster development of ESIMs, while providing appropriate protection to other GSO and non-GSO systems, as well as terrestrial services, explained Mr. Malaguti.
The second decision was the allocation of the frequency band 51.4-52.4 GHz to the fixed-satellite service (FSS) for geostationary satellite use, providing an additional 1 GHz of spectrum for supporting gateway links for very high-throughput satellites
Following the previous two WRCs and the recently announced WRC-23 agenda, “satellite operators are responding with investments of billions of dollars,” said Daryl Hunter, Chief Technology Officer at Viasat. This positive response from operators is also demonstrated by “a tripling down of satellite activities in the 28 GHz band,” he added.
Echostar Vice President of Regulatory Affairs Kimberly Baum agreed, noting how satellite broadband revenue and subscribership grew by 19 per cent and 10 per cent last year. “By 2026, Northern Sky Research (NSR) predicts 10 million GSO broadband subscribers globally," Baum noted, adding how this growth is occurring as operators bring more satellites to the market.
“There is a good chance you have already used Ka band GSO ESIM service if you have flown on commercial air service,” pointed out Mr. Hunter, highlighting how in-flight connectivity (on-board Wi-Fi) relies on GSO satellite services.According to Viasat, there are now more connected devices than passengers, with annual ESIM flights exceeding 1.83 million last year.
GSO satellites and related equipment also seem to have ‘tripled down’ in size, with design and technology innovations shrinking building-sized communications panels to about the size of a microwave. “Gateways themselves have also shrunk from 11 metres to around two metres,” pointed out Mr. Hunter. “We are operating as small as 30-centimeter ESIMs mounted on the tail of some small aircraft,” he added, noting how ViaSat thinks it can get smaller with spread-spectrum techniques.
Flexibility, integration and mission extension
Flexible, high-throughput satellites are high on operators’ innovation agendas, with Intelsat Vice President of Spectrum Strategy Hazem Moakkit sharing plans for the launch of software-defined satellites. These new designs enable operators to change frequencies, move beams, shape coverage and manage power on each satellite, offering “unparalleled flexibility in terms of providing services and surgically targeting areas where you need capacity,” explained Mr. Moakkit.
Jonas Eneberg, Vice President of Regulatory Engineering at Inmarsat agreed, noting how dynamically adjusting deployment of satellite capacity makes its operation much more efficient. “Compared to LEO constellations, flexible GSO satellites are more efficient because they can avoid having capacity in coverage areas where there is low traffic demand,” he explained.
Another exciting advancement is the possibility to extend the life of GSO satellites, which normally have a lifespan of around 15 years, according to Mr. Moakkit. Earlier this year, Intelsat and Northrop Grumman achieved an historical milestone with the industry’s first life extension vehicle bringing another commercial satellite back into service.
“When satellites go out of service, it is not because their electronics stop operating but because the satellite runs out of propellant,” he explained. “This is one way to keep using satellites that improves the business case, and the efficiency of the overall business offering.”
Crucial to the success of software-defined satellites is the integration and upgrade of traditional architecture, said Mr. Moakkit, noting how “satellite technology will go from hardware-based and proprietary to standards-based and virtualized.” The emphasis will fall increasingly on service and value in the form of managed solutions and applications, instead of selling MHz and Mbit/s, Mr. Moakkit said. Software-defined satellites aim to get closer to customers for more flexibility, shorter-term commitments, and seamless connectivity, which is what customers expect now, he added.
Expanding affordable connectivity
One of the more important uses of GSO broadband satellites is powering community Wi-Fi in underserved areas by placing a VSAT antenna on a central location in a town, such as a government building or store. The modem is connected to a WiFi access point to provide broadband connectivity to customers in a 100-metre radius.
Retailers can then sell data packs to the public, or the service could be subsidized by the government and offered for free, as in the Curacao, Brazil example shared by Ms. Baum. Northern Sky Research (NSR) predicts that by 2027, 40 per cent of overall revenue from satellite broadband will be from this kind of community WiFi hotspot, pointed out Ms. Baum.
Mr. Hunter shared the example of Viasat Community Internet, which is aiming to offer broad coverage in remote places with limited connectivity, what he referred to as “0G service – where people have to drive to get coverage.” Claiming that Viasat can drop connectivity into that kind of location within a day, Mr. Hunter noted that “Ka band coverage and capacity are key” to making that happen. In Brazil, for instance, many people lack internet outside large cities. The telecommunications company Telebras is working with Viasat to connect every Brazilian, he added.
Learning to live together
As spectrum is a limited natural resource, it needs to be shared among different types of services and even different types of satellite constellations, such as low-Earth orbit (LEO) and medium-Earth orbit (MEO) systems which are non-geostationary (non-GSO) by definition.
An audience poll revealed that the main challenge for GSO satellite operators is staying competitive with non-GSO systems whose sharing capacity is increasing, which might explain why 53 per cent of webinar viewers felt that GSO systems should continue to benefit from the regulatory advantage contained in the Radio Regulations.
While panellists agreed that sharing spectrum is necessary to make use of current and future innovation in satellite technology, they pointed out difficulties when it comes to GSO site coordination or time-sensitive activities.
“We can deploy a new broadband terminal in two days. To do that, we don’t have time to go through a site coordination process,” said Ms. Baum. “We need access to spectrum for those user terminals that isn’t shared so that we can deploy quickly in a given country.”
GSOs and WRC-23
The use of additional frequency bands for ESIM communicating with GSO space stations in the fixed-satellite service (FSS) will be considered at the next World Radiocommunication Conference in 2023 –globally and for all regions, reminded moderator Mr. Malaguti.
The second GSO-relevant agenda item deals with the provision of satellite-to-satellite links in a different set of bands, as Mr. Maniewicz pointed out. “ITU-R Study Group 4 is evaluating ways to improve space-to-space communications including with GSO satellites so growing traffic demand can be absorbed by inter-satellite links,” he explained.
“Among those links are GSO stations where you establish links with non-GSO satellites - a very interesting agenda item for the next conference,” added Mr. Malaguti. Mr. Eneberg of Inmarsat agreed, highlighting how there is definitely a market for GSO providers serving non-GSO satellites through inter-satellite links, with a lot of interest from non-GSO operators.
Looking ahead, “new generations of high-throughput satellites and new services are going to benefit the global customer base,” affirmed Mr. Hunter, suggesting a bright future and more innovations to come.
Missed the ITU satellite webinar series? You can view the recordings or download the presentations from all previous episodes here.
Did you enjoy the ITU satellite webinars? Have a look at the programme of the upcoming World Radiocommunication Seminar (WRS-20), an entirely virtual event whose Plenary Sessions are open for the first time to all those interested! From 30 November until 4 December, ITU will hold two sessions a day in order to accommodate participants from most time zones. Learn more and register here.
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