Minimize ISS Optical Communication Demo

ISS Optical Communication Demonstration - a critical implementation for the future

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August 2, 2021: SpaceLink of McLean, VA, a company that is building the communications superhighway for the space economy, announced that it was selected by the Center for the Advancement of Science in Space (CASIS), manager of the International Space Station U.S. National Laboratory, for a funded demonstration of its end-to-end relay service which provides secure, continuous, high capacity communications between spacecraft and the ground. The demonstration will validate the use of a 10 Gbit/s optical terminal, for real-time voice, video, and data exchange between the ISS crew, onboard systems, experiments, and terrestrial users. 1)

In a highly competitive process, made available for companies and research teams to propose technology development concepts capable of being utilized in low Earth orbit (LEO), the SpaceLink concept was selected by CASIS. With this selection, SpaceLink can advance its proposal for a potential flight project to the orbiting research and technology development outpost sponsored by the ISS National Lab. The SpaceLink relay network is designed to pick up where the NASA Tracking and Data Relay Satellite System (TDRSS) leaves off and go beyond with unprecedented capacity that leverages the latest technology advances in optical communications.

"Our demonstration on the ISS is the first step to proving SpaceLink's capabilities to advance space science and the emerging space economy," said David Bettinger, SpaceLink CEO. "Funding from CASIS marks an important milestone in SpaceLink's roadmap to providing massive bandwidth for organizations that need real-time connectivity between space and the ground."

With the proliferation of spacecraft in LEO, the demand for fast, continuous, high-capacity connectivity on orbit continues to grow. SpaceLink is designed to help close the business case for Earth observation companies, commercial space stations, satellite servicers, launch vehicles and space tugs. It also meets requirements for the U.S. Government and close allies that want to leverage secure industry solutions to maximize capabilities.

On July 28, 2021 CASIS notified SpaceLink of its intent to award a User Agreement. A fully executed agreement with program schedule and milestone deliverables is expected to be completed in the coming months.


Development status

• February 17, 2022: SpaceLink announced plans to work with Axiom Space to conduct the first demonstration of its space data relay service on the International Space Station. 2)

- CASIS, manager of the ISS National Laboratory, awarded McLean, Virginia-based SpaceLink a contract to demonstrate data transmission from the Space Station through optical terminals at a rate of 10 gigabits per second.

- Once that contract was finalized, SpaceLink awarded Axiom a subcontract to support mission integration, launch and operations. Axiom also will serve as SpaceLink's liaison with NASA, ensuring SpaceLink hardware meets stringent ISS safety requirements.

- SpaceLink CEO Dave Bettinger called the demonstration, scheduled for 2024, "an excellent validation to a show data rates to the ISS that I believe are potentially one or two orders of magnitude higher than what they've seen."

- OHB System AG is manufacturing four satellites, which it plans to send to medium Earth orbit (MEO) in 2024, to relay data for government and commercial customers. The planned service is similar to what NASA provides today through the Tracking and Data Relay Satellite constellation in geostationary orbit.

- "We see it as a an important milestone for us to show NASA and the world that we are going to be able to provide the services in space that commercial, government and international entities will be using in the future," Bettinger told SpaceNews.

- Axiom won a NASA contract in 2020 to develop a commercial module for the Space Station. Axiom also is planning a series of commercial ISS missions.

- "High-speed communication will be a critical component for the future where people live and work in space," Michael Suffredini, Axiom president and CEO, said in a statement. "Axiom looks forward to collaborating with SpaceLink and supporting its relay network, beginning with this important demonstration on the ISS."

- SpaceLink plans to conduct the data relay demonstration in 2024 after testing in-orbit testing of its communications satellites.

- "NASA has done a great job of going commercial where it makes sense and saved a lot of money on that," Bettinger said. "We see this as a perfect example. We're very proud to be a part of the CASIS project."


Figure 1: This illustration shows SpaceLink's optical terminal mounted on the first module of the future Axiom Station. SpaceLink plans to establish a satellite constellation in medium Earth orbit to relay radio frequency and optical data between satellites in low Earth orbit and the ground (image credit: SpaceLink)

• October 13, 2021: SpaceLink has awarded OHB System AG a contract with an anticipated value of more than $300 million to manufacture four satellites for its commercial space data relay constellation. 3)

- After reviewing proposals from multiple satellite manufacturers, SpaceLink selected OHB based on a number of factors including the German company's experience building Galileo navigation satellites for medium Earth orbit.

- "They've done optical and onboard processing before, so they're ideal for us in terms of having relevant experience in all of the key technologies," Tony Colucci, SpaceLink chief strategy and commercial officer, told SpaceNews. "Also, they have a good reputation for delivering on schedule, which is another important factor for us. Obviously, we want to get our revenue started as soon as we can."

- OHB announced plans to invest $25 million investment in SpaceLink, making OHB "the cornerstone investor in the initial round of financing for the project," according to an Oct. 13 news release.

- "For SpaceLink, we are providing a highly reliable and cost-effective solution based on our modular satellite platform, which has been successfully proven on multiple critical missions," Marco Fuchs, OHB SE CEO, said in a statement. "We look forward to working together with the SpaceLink team to help launch this important resource for real-time space connectivity."


Figure 2: SpaceLink awarded OHB System AG a contract in valued at more than $300 million to manufacture four satellites for its commercial space data relay constellation (image credit: SpaceLink)

- McLean, Virginia-based SpaceLink plans to establish a relay network in medium Earth orbit to connect commercial and government satellites with customer mission operations centers. Customers with satellites in low Earth orbit will relay RF and optical data through SpaceLink's medium Earth orbit (MEO) constellation to and from ground stations. SpaceLink satellites will be equipped with laser crosslinks to route data traffic quickly through the network.

- "That space economy is literally mushrooming [and] the bottleneck of communications between LEO and the ground is becoming more and more a problem," Colucci said. "As that economy evolves, the need to have real-time and high-bandwidth communications increases."

- SpaceLink's initial constellation requires three satellites to provide global coverage. The company plans to launch four satellites to provide on-orbit redundancy. SpaceLink satellites are scheduled to begin launching in 2024, but the company has not yet decided whether to send them to orbit on a single rocket.

- "There are advantages to launching all at once, from getting the whole system up and operating at the same time, and costs advantages for one launch over two," Colucci said. "And then of course you always have to trade off putting all your eggs in one basket."

- Under SpaceLinks' agreement with OHB, roughly half of the satellite subsystems and components will come from U.S. suppliers.

- "For SpaceLink, our customer base will be a mix of commercial and government customers, and not just U.S. government, but we anticipate allied governments will ultimately use the services as well," Colucci said.

- SpaceLink expects more than half the data carried by its network, whether it originates from commercial satellites or from government satellites, to flow to government end users.

- "There are, of course, certain security requirements involved there," Colucci said. "Having key payload technologies and equipment that's manufactured in the U.S. just makes that a simpler case for the U.S. players."

- As soon as SpaceLink selected OHB, the two companies "commenced a co-engineering effort in Germany to finalize the satellite design," SpaceLink CEO Dave Bettinger said by email. "The design is significantly improved from earlier versions due to the talent and experience of the combined SpaceLink and OHB team. Our customers are very excited and we are working with several of them to integrate optical intersatellite links on their spacecraft."

- SpaceLink is financing its initial constellation through equity.

- "For a project like this there's a substantial amount of equity required before debt comes in," Colucci said. "We expect to bring in some debt, probably in the 2023-2024 timeframe, but this year and next we'll be financing it through rounds of equity."

- In many satellite constellations, though certainly not every deal, manufacturers like OHB sign on as strategic investors, Colucci said. Sometimes other constellation partners also become strategic investors, "but in our case we're trying to keep this to a minimum ... because, of course, we already have EOS. OHB and EOS have a long-standing close relationship, so this one just seemed to be a good fit."

- On the regulatory side, SpaceLink "remains on track" to meet its 2024 Federal Communications Commission license deadline, Bettinger said. SpaceLink's International Telecommunications Union spectrum filings do not expire until 2028.

- Australia's Electro Optic Systems Holdings Ltd. (EOS) announced plans in 2020 to spend approximately $1.2 billion Australian dollars (about $800 million at the time) to create the SpaceLink constellation.

- OHB built 34 Galileo navigation satellites, which operate in medium Earth orbit. The company based in Bremen, Germany, also manufactured the European Data Relay System-C, a geostationary satellite with RF and optical communications payloads.

• August 3, 2021: Significantly faster communications could be coming to the International Space Station in 2024, after SpaceLink won funding to test its incoming relay satellites. 4)

- The Center for the Advancement of Science in Space (CASIS), which manages the U.S. National Laboratory on the ISS, selected the startup to test its 10 gigabit per second (Gbit/s) optical terminal from the station.

- The funding amount and the contract's length remain unfinalized, although SpaceLink chief technology officer Rob Singh told SpaceNews it aims to launch its first satellites in 2024.

- McLean, Virginia-based SpaceLink plans a relay constellation of four spacecraft in medium Earth orbit (MEO), which will primarily deliver services to satellites in low Earth orbit.

- According to SpaceLink, its satellites at higher altitudes will always be visible to spacecraft in LEO and a gateway ground station on Earth, enabling direct data delivery to any point on the globe in milliseconds.

- Its ISS demo mission aims to validate SpaceLink's hybrid optical and radio frequency (RF) network, and optical terminal technology, which the crew can use for onboard systems, experiments, and communications with people on the ground.

- Singh said the relay network would pick up where the NASA Tracking and Data Relay Satellite System (TDRSS) leaves off to enable real-time connectivity.

- "Comparing to what we know about the Ka-band RF single-access service, SpaceLink will provide a similar high capacity 100-600 Mbit/s service for RF users," said Singh, who is principal investigator for the ISS demo mission.

- "SpaceLink will also provide higher capacity optical links of 1-10 Gbit/s for optical clients."

- SpaceLink, formed by Australia's Electro Optic Systems (EOS) in 2020, won the ISS contract following a competitive selection bidding process.

- CASIS notified SpaceLink of its intent to award a User Agreement July 28. The startup expects a full agreement, comprising program schedules and milestone requirements, will be ready in the coming months.


Figure 3: SpaceLink's constellation aims to continuously transmit user data to the ground for immediate access via the internet, private cloud, or other secure delivery (image credit: SpaceLink)

- A group of European companies is developing a separate 10 Gbit/s optical terminal called Osiris for Bartolomeo, Airbus Defence and Space's external research platform on the ISS.

- Airbus teamed up with DLR, Germany's space agency, and German laser communications company Tesat Spacecom for the project, which had planned to deploy Osiris in 2021.

- However, a DLR spokesperson told SpaceNews that Osiris will not be installed this year.

- Airbus and Tesat Spacecom directed questions to DLR, which said there is no time frame for installing it.

- "Our understanding is that the [planned] Airbus optical link is directly to the ground," a SpaceLink spokesperson added.

- "SpaceLink will provide an optical relay service from the ISS through our MEO constellation and then to the ground. This architecture provides for 24/7 constant contact with the ISS with an optical relay solution."

• December 8, 2020: Electro Optic Systems (EOS) of Australia formed SpaceLink, a wholly owned U.S. subsidiary to provide data-relay services for satellites in low Earth orbit and named former OneWeb Vice President David Bettinger as its chief executive officer. 5)

- "We are developing and implementing a commercial, medium Earth orbit data-relay service to provide direct access from LEO satellites to the ground within milliseconds," Bettinger said.


Figure 4: SpaceLink plans to send three satellites into medium Earth orbit to relay data between the ground and low Earth orbit. David Bettinger, a former Hughes Network Systems, iDirect and OneWeb executive is the SpaceLink CEO. © 2019 (image credit:Kristina Sherk Photography)

- EOS, which acquired Silicon Valley startup Audacy in May, plans to establish its initial data-relay constellation with three satellites in 2023.

- "We hope to have our second-generation constellation within two years of that first launch," Bettinger said.

- The first two generations of SpaceLink satellites will focus on radio frequency communications. The third generation will transmit data through RF and laser links, Bettinger said.

- SpaceLink plans to establish an office in McLean, Virginia, a facility in Palo Alto and a secure satellite operations center in Huntsville, Alabama, co-located with EOS Defense Systems. In addition to Bettinger, the company has hired about a dozen engineers and executives.

- SpaceLink plans to cater to a diverse group of customers including Earth observation satellite operators, human spaceflight missions, in-orbit satellite servicing companies, and defense and intelligence agencies.

- "We like to think of ourselves as a secure Wi-Fi network in space, providing fast, affordable access," Bettinger said.

- Bettinger began his career at Hughes Network Systems, before joining iDirect and later OneWeb, where he was responsible for the communications network's technology roadmap including the satellite payload, user terminals and ground segment.

- "SpaceLink is an important part of the EOS strategic ecosystem, which brings synergies to all three of our business units – Space Systems, Defence Systems, and Communications Systems," Glen Tindall, EOS Communications Systems CEO, said in a statement. "David's track record of transforming startup ventures into a competitive position makes him the ideal CEO to lead the SpaceLink effort to meet the growing demand for continuous connectivity from LEO."

1) "SpaceLink Selected to Fly Demo on International Space Station," SpaceLink, 2 August 2021, URL:

2) Debra Werner, "SpaceLink hires Axiom to support ISS communications demonstration," SpaceNews, 17 February 2022, URL:

3) Jason Rainbow, Debra Werner, "SpaceLink hires OHB to build data relay satellites," SpaceNews, 13 October 2021, URL:

4) Jason Rainbow, "SpaceLink to improve International Space Station comms with relay satellites," SpaceNews, 3 August 2021, URL:

5) Debra Werner, "EOS establishes SpaceLink with Dave Bettinger at the helm," SpaceNews, 8 December 2020, URL:

The information compiled and edited in this article was provided by Herbert J. Kramer from his documentation of: "Observation of the Earth and Its Environment: Survey of Missions and Sensors" (Springer Verlag) as well as many other sources after the publication of the 4th edition in 2002. - Comments and corrections to this article are always welcome for further updates (

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