Irish firm Celtonn making waves in the space race

Celtonn CEO Marie Bourke talks to George Morahan about how the startup’s tech is getting them noticed in the satellite industry

For the past two years, space technology startup Celtonn — pronounced Kel-tonn, a portmanteau of Celtic and tonn, the Irish word for wave — has been developing millimetre wave (mmWave) sensors.

MmWave is expected to underpin next-generation 6G data communications, weather forecasting, medical imaging and satellite systems among other applications, and it has been a topic of research for Celtonn cofounder and chief technology officer Dr Mark Kelly for four decades.

Dr Kelly, a serial entrepreneur and former principal engineer at Queen’s University Belfast, founded Celtonn with his daughter and chief operations officer Aoife Kelly, Taiwan-based vice president of engineering Yulung Tang and chief executive Marie Bourke.

A qualified microbiologist, Cork native Bourke has been working in the area of radio frequencies (RF) since 2011, although as chief executive she says her responsibilities are more commercial than technical.

Bourke worked with Dr Kelly and Tang at Arralis for several years, and when the Limerick space tech firm’s backers decided to pull out of the European market, they launched Celtonn with a number of patents already in Dr Kelly’s name.

While working at Arralis, Dr Kelly and Tang spoke about setting up a company to fulfil their ambitions of “pushing the boundary of what the technology can do”, Bourke says.

The specific technology in question is semiconductors (or chips) for next generation satellites that use extremely high radio frequency bands within the mmWave spectrum.

At the time of the company’s establishment, Celtonn’s founders said in a press release that they had managed to address high path loss and atmospheric attenuation, challenges commonly associated with designing mmWave modules.

The higher the frequency, the narrower the band becomes.

Different frequencies have different properties, so they can penetrate different atmospheric conditions and with each new band comes different challenges, according to Bourke.

Celtonn designs, builds and tests semiconductors and the electromagnetic housing in which they sit. The housing can then be inserted into the client’s satellite components.

The company’s technology is currently being tested by one largescale aerospace original equipment manufacturer (OEM) as part of a commercial pilot.

“It’s getting that data of how the customer interfaces with our product and exactly what pain points it’s solving for them,” Bourke says of the process.

After exhibiting at the European Space Tech Expo in Bremen recently, there was mention of the company potentially working with Elon Musk’s SpaceX, albeit through a third party.

Self-funded at start-up, Celtonn’s “first validation” came when it was selected to join the European Space Agency’s Business Incubation Centre Ireland programme in mid-2023.

Earlier this year, the company signed a contract to develop semiconductors for next-generation satellites for ESA.

The firm, which recently moved its base from the Nexus Innovation Centre at the University of Limerick to NovaUCD, is finalising a second contract with the ESA to commence in January.

A planned €1.5m funding round has been cancelled as a result.

“We’ve decided that we have sufficient runway at the moment, and we want to keep the cap table as clean as we can,” Bourke says.

“We have four co-founders, which I suppose for some investors is probably enough or too much … but we very much want to dictate the trajectory of the company for now.

“We feel with the four of us that we know where we want to take the company, so I suppose we are going to try and hold off as long as we can before having outside investors come in.

“I think if we want to go to the next level, we [will look] at taking on investment to be able to do that.

“But, at the moment, thankfully, we are able to fund ourselves and the research we want to carry out.”

The first ESA contract specifically related to the development of an amplifier for V-band feeder uplink. V-band refers to the microwave portion of the electromagnetic spectrum ranging from 40 to 75 GHz, which is less crowded with satellites than the lower radio frequency K-band (18- 27GHz) and Ka-band (27-40GHz).

It is believed that SpaceX will be launching much of their satellite constellation in the V-band for its wider data transmission capabilities.

Details of the second ESA contract are yet to be announced, but it will be focused on the D-band (110-170GHz).

According to Bourke, D-band is not as developed as the lower frequency bands, but it is an area of interest for ESA, which is working with companies such as Celtonn to future-proof it.

In October 2024, Celtonn showcased the terabit-level data rates of its D-band technology at CERN.

However, the options for fabricating D-band chips are limited to prohibitively expensive research-based foundries.

A commercial foundry process will need to be developed for the chips to become commercially viable.

“That’s really where we see the market going. It’s an enabling technology for the likes of 6G, for AI — you’re talking about massive bandwidth,” Bourke says of D-band.

“Data transmission is hugely important, so it’s only with technology like D-band [radio frequencies] that you can transmit the level of data that you need to be able to meet those requirements.

“For D-band, you’re talking about a billion bytes of data per second potentially that you can transmit.”

Also in October, the company completed CASSINI Business Accelerator, a Europe-wide incubator for high-potential space scale-ups.

Bourke describes the six-month programme as being “really intensive” and helpful as Celtonn prepares to enter the US satellite market.

“It gave us access to some really good European VCs and they allowed us to refine our business offering and our route to market with the aim of entering the US satellite market in the next year or so,” she says.

“The mentors they give you access to are unbelievable. They would have connections to the likes of SpaceX and some really, really good deep tech VCs as well.”

At the time of our interview in early December, two of Bourke’s co-founders had travelled to Italy to meet with a VC from Blue Tech Mountain.

The company is preparing to start work on its second ESA contract in January.

Next year Celtonn also intends to increase its headcount from four to six, although finding engineers with the required skillset is a challenge.

The firm is also intent on making its systems smaller and more accessible for prospective clients in the aerospace and satellites markets.

“Our devices will fit in the palm of your hand, but they need to be so small that it fits on a chip essentially with the idea that it can be based within your mobile phone,” Bourke says.

CASSINI put a renewed emphasis on refining its offering, and Bourke believes Celtonn can be a “point of difference in the market”, providing customers with a “competitive edge”.