CesiumAstro: filling the gap for space communication
Space is hard, nothing exactly goes to plan, and there are always surprises, were the sage words of advice from Shey Sabripour, CEO of CesiumAstro, a Texas-based startup specialising in phased array technology.
This fundamental understanding of just how challenging designing and developing space technology is has steered the company from its founding in 2017 to today, with a team of more than 300 members and offices located across the US, UK, Germany, and Japan.
For Sabripour, being drawn to “how complex systems come together to solve real problems” marked the beginning of a journey that eventually culminated in the founding of CesiumAstro in Austin, Texas.
Drawing on his experience of 24 years at Lockheed Martin and time spent at Firefly Space Systems – a startup building a launch vehicle from the ground up – a “fast paced, challenging, and deeply rewarding” career meant he was in a good position to understand what was needed to establish a spacetech startup.
Phased array technology
Enter CesiumAstro, whose goal from the outset was “to build space communications systems that were as scalable and agile as the missions they needed to support,” according to Sabripour, including providing global connectivity. It designs and manufactures active phased array payloads – antenna systems that electronically steer a beam of radio waves without moving the antenna – and oversees the entire process, from digital design to embedded software and in-house manufacturing.
“Phased array technology has been around for decades in aerospace and defence applications,” said Sabripour. “But historically, they were expensive, bespoke, and slow to deploy.”
This is a thing of the past, according to Sabripour: “Previously I worked on satellites where the communications payloads took years to develop and cost more than most startups raise in a lifetime. They were remarkable feats of engineering but were not commercially scalable.
“That said, affordability isn’t a compromise. Affordability is a product of smart engineering. In this industry there are always trade-offs. To help our customers avoid those pain points, we focus on scalability, repeatability, and tight integration … this can certainly take time.”
This affordability is achieved by building its phased arrays using commercial off-the-shelf components, as well as carrying out design, testing, and manufacturing all in-house, “reducing cost, accelerating timelines, and ensuring quality control at every step.”
By re-engineering phased array systems from the ground up, CesiumAstro was able to build a brand-new architecture that made its technology modular, software-defined, and ready to be scaled.
“Take our Vireo Ka-band communications system. It supports multiple simultaneous RF beams from a single aperture, with real-time beam steering and flexible power allocation. But as important as what it does is how it was designed. Vireo wasn’t just an R&D challenge – it was an industrialisation challenge,” said Sabripour.
Focusing on both the hardware and software at the same time was a conscious decision.
“Hardware sets the performance limits. Software drives what the system actually does,” added Sabripour. “If you only do one, you are flying blind on the other.”
This is what sets it apart from its competitors, whom Sabripour classified as falling into one of two groups: companies that focus solely on components, or companies that focus solely on highly custom solutions.
“We build complete, productised systems that are ready for mission deployment, not just for one customer, but across programmes and platforms,” he explained.
Its current customers include US government agencies such as the Department of Defense and NASA, for projects ranging from LEO networks to ground connectivity and lunar infrastructure, on top of commercial constellation operators and aerospace primes (AKA prime contractors; companies that are contracted for major aerospace and defence projects).
Scaling space communications
There are two areas which CesiumAstro has identified as growth areas going forward: multi-beam connectivity and resilient defence communications.
“As hybrid constellations mature and the need for secure, low-latency, space-based infrastructure continues increasing, especially for contested and denied environments, our technology is ready.”
Scaling quickly, Sabripour is excited about the future: “Our systems and satellite are already in orbit, under contract, and in production, and now we’re expanding to meet the demand,” he said. “That means growing our manufacturing capacity, fulfilling major defence and commercial programmes, and powering the next generation of space and airborne networks.”
Having achieved this level of scale has been a highlight for the company, in addition to delivering Vireo systems into its customers and phased array payloads and integrated satellites for security, commercial, and lunar sessions.
However, Sabripour noted the work he was proud of, he couldn’t speak explicitly about due to the customers they worked with.
“I still believe our most important milestones are ahead of us … the world is changing fast, and we are right in the middle of some of the most consequential programmes out there,” he said.
The future is bright for CesiumAstro, who is operating in a market that is only due to grow and expand, due to the role satellite communications can play in delivering global connectivity and filling in the gaps where terrestrial infrastructure fails.
“Space communications is no longer just a ‘technology challenge.’ It is an infrastructure requirement,” said Sabripour. “Right now, secure, high-throughput connectivity is critical across commercial and defence and scientific operations.
“Space is no longer the future. It is the present. And connectivity is what holds it all together.”
This article originally appeared in the July/August 2025 issue of Startups Magazine. Click here to subscribe
