cFLOW · Project

Infrared Laser Links for Ultra-Fast Wireless Data Transfer Through Fog and Rain

digitalPrototypeTRL 4Thin data (2/5)

Imagine beaming internet through the air using invisible infrared light — the same kind of heat radiation a warm stove gives off. Regular laser links struggle in fog and rain, but this team built chips that operate in a special infrared "sweet spot" (8-12 micrometers) where the atmosphere barely interferes. They demonstrated wireless data speeds of 20-100 Gbps — fast enough to download a full movie in under a second — using compact laser chips that work at room temperature without bulky cooling systems.

By the numbers

20-100 Gbps

Demonstrated wireless data transmission speed

>20 GHz

Modulation speed of QCL chip and heterodyne sensor

1000x

Sensitivity improvement over current infrared detectors (three orders of magnitude)

100%

Modulation depth achieved

8-12 μm

Long-wave infrared operating wavelength range

Consortium partners across 4 countries

Demo deliverables (FSO modules and PIC chips)

The business problem

What needed solving

Wireless data links today face a tough tradeoff: radio frequency connections work through bad weather but max out on speed, while conventional laser links are fast but fail in fog and rain. Businesses needing high-bandwidth wireless connections — between buildings, across campuses, or in remote locations — are stuck choosing between reliability and performance. There is no current commercial solution that delivers fiber-like speeds (100 Gbps) wirelessly with high atmospheric resilience.

The solution

What was built

The team built Gen 2 and Gen 3 free-space optical communication modules (both source and receiver units) along with matching photonic integrated circuit chips (Gen 2 and Gen 3 PIC chips). These are physical hardware demonstrators for infrared wireless data links operating at 20-100 Gbps in the 8-12 micrometer wavelength band.

Audience

Who needs this

Telecom operators needing high-speed building-to-building backhaul without fiber trenchingDefense contractors building jam-resistant tactical communication systemsData center operators connecting campus buildings at fiber-equivalent speedsSatellite ground station operators requiring high-bandwidth optical feeder linksIndustrial site operators in remote locations needing fast connectivity without cable infrastructure

Business applications

Who can put this to work

Telecommunications

enterprise

Target: Wireless network operators and ISPs deploying last-mile connectivity

If you are a telecom operator dealing with the cost and delay of laying fiber in dense urban areas or across difficult terrain — this project developed infrared free-space optical modules capable of 20-100 Gbps that work through fog and rain far better than conventional laser links. The Gen2 and Gen3 FSO modules demonstrated could replace expensive fiber trenching for building-to-building backhaul.

Defense and Security

enterprise

Target: Defense contractors building secure tactical communications

If you are a defense systems integrator struggling with RF jamming and interception risks in battlefield communications — this project built long-wave infrared transmitters and receivers with sensitivity three orders of magnitude higher than current solutions. The narrow infrared beam is extremely difficult to detect or intercept, and operates at 20-100 Gbps for real-time video and sensor data relay.

Data Centers and Cloud Infrastructure

enterprise

Target: Hyperscale data center operators needing inter-building links

If you are a data center operator facing bandwidth bottlenecks between campus buildings where fiber installation is impractical or too slow to deploy — this project created photonic integrated circuit chips (Gen 2 and Gen 3 PIC chips) enabling coherent free-space links at 20-100 Gbps. These room-temperature devices eliminate the need for expensive cooling while delivering telecom-grade modulation speeds above 20 GHz.

Frequently asked

Quick answers

What would this technology cost compared to fiber optic installation?

The project does not publish cost figures. However, free-space optical links eliminate trenching and civil works — often the most expensive part of fiber deployment. The room-temperature operation of these QCL chips avoids costly cryogenic cooling, which should reduce both capital and operating costs compared to earlier infrared systems.

Can this scale to production volumes for commercial deployment?

The project produced Gen 2 and Gen 3 photonic integrated circuit (PIC) chips, which is the standard manufacturing approach for scaling photonics. PIC-based designs are inherently suited to wafer-scale production. However, this was a research project with 9 partners and the technology would need further engineering for volume manufacturing.

What is the IP situation — can we license this technology?

The project was funded under FET-Open (FETOPEN-01-2018-2019-2020), where IP typically stays with the consortium partners. The coordinator is III-V LAB in France, a specialized semiconductor lab. Licensing discussions would need to go through the consortium, particularly III-V LAB and the industrial partners.

How does this perform in bad weather compared to existing wireless links?

The core advantage is operating in the 8-12 micrometer long-wave infrared window, which has extremely low sensitivity to atmospheric perturbation according to the project data. This means fog, rain, and dust affect these links far less than conventional telecom-wavelength laser links or millimeter-wave RF.

What data speeds were actually demonstrated?

The project targeted coherent transmission at 20-100 Gbps using devices with modulation speeds above 20 GHz and 100% modulation depth. The heterodyne receiver achieved sensitivity three orders of magnitude higher than current solutions. Gen 2 and Gen 3 FSO modules were built as demonstrators.

Is this ready for field deployment today?

Based on available project data, this is at the advanced prototype stage. The team delivered Gen 2 and Gen 3 free-space optical modules and PIC chips, but this was a FET-Open research project focused on proving the science. Field-hardened, weather-tested commercial products would require further development and industrial engineering.

Consortium

Who built it

The cFLOW consortium brings together 9 partners from 4 countries (Austria, Switzerland, France, Sweden), led by III-V LAB, a French semiconductor research facility specializing in III-V compound materials — the exact materials these quantum cascade lasers are built from. The consortium is heavily research-oriented: 4 universities and 3 research organizations versus just 1 industrial partner, giving an industry ratio of only 11%. There is 1 SME in the group. This composition is typical for a FET-Open project pushing fundamental science boundaries. For a business looking to adopt this technology, the low industry participation means there is no established commercial partner yet — which is both a risk (longer path to market) and an opportunity (early mover advantage for a company willing to co-develop).

III-V LABCoordinator · FR
TOTALFORSVARETS FORSKNINGSINSTITUTparticipant · SE
TECHNISCHE UNIVERSITAET WIENparticipant · AT
CSEM CENTRE SUISSE D'ELECTRONIQUE ET DE MICROTECHNIQUE SA - RECHERCHE ET DEVELOPPEMENTparticipant · CH
KUNGLIGA TEKNISKA HOEGSKOLANparticipant · SE
ECOLE NORMALE SUPERIEUREthirdparty · FR
UNIVERSITE PARIS CITEthirdparty · FR
MIRSENSEparticipant · FR
CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRSparticipant · FR

How to reach the team

III-V LAB (France) — a semiconductor research lab specializing in III-V materials for photonics. Contact through their institution or via SciTransfer for a facilitated introduction.

Order a report on this consortium See III-V LAB profile →

Next steps

Talk to the team behind this work.

Want to explore licensing or co-development of this infrared communication technology for your network? SciTransfer can arrange a direct introduction to the cFLOW research team and help structure the conversation around your specific use case.

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