Senior Software Engineer - QRF

Infleqtion secures UK funding for quantum signal-tracking system. 2 minutes read UK-based Infleqtion has received 9 million pounds ($12 million) from the country's national innovation agency to develop a deployable quantum sensing system that can determine the direction of radio frequency (RF) signals, with potential applications in electronic warfare, spectrum monitoring, and navigation. The funding, awarded through UK Innovate's Quantum Missions Primer program, will support the second phase of the Quantum Direction Finding (QuDiFi) project. The project aims to move the technology from prototype testing toward a deployable product, with further work focused on performance, reliability, and evaluation in realistic operating environments. Infleqtion is developing a system called Quantum Spectrum-DF in collaboration with Italian defense company Leonardo. The companies have not disclosed a timeline for operational deployment. Using quantum sensors to locate radio signals. Direction-finding systems determine the direction from which a radio signal originates, helping operators locate transmitters and monitor activity across the electromagnetic spectrum. Military users can apply the technology to electronic intelligence and electronic warfare, while civilian applications include communications monitoring and infrastructure protection. Conventional systems often use multiple antennas to estimate a signal's direction. At lower frequencies, achieving the required performance can involve large antenna structures, creating size and integration challenges for mobile platforms. Infleqtion's approach uses Rydberg atoms, highly excited atoms that are sensitive to electric fields, to detect radio-frequency signals through optical measurements. By analyzing how these atoms respond to electromagnetic fields, quantum sensors can measure RF signals without relying on conventional antenna elements in the same way as traditional systems. The approach could reduce the size of direction-finding equipment and make it easier to integrate onto platforms with limited space. However, its practical advantages will depend on demonstrated performance under operational conditions, including the ability to identify and locate signals amid interference and competing transmissions. Defense and civilian applications. Leonardo is contributing to the effort, with potential applications across its defense electronics portfolio. Compact RF sensing could be relevant to aircraft, naval vessels, and other platforms where the size, weight, and power requirements of electronic systems are important considerations. The technology could also support passive sensing, which receives and analyzes existing transmissions rather than actively emitting a signal. Potential applications include spectrum surveillance and navigation, although these capabilities would require further development and validation. The project builds on broader UK efforts to advance quantum technologies for practical use. Quantum sensing is being investigated for applications including navigation, timing, and the detection of physical phenomena that conventional sensors may struggle to measure. For Infleqtion, the immediate objective is to establish whether Rydberg-atom sensing can deliver reliable direction finding in a compact, field-ready system. The funding will support that development, but the technology's eventual military and civilian roles will depend on the results of testing and subsequent integration work.

Infleqtion wins £9 million for quantum radio direction-finding. Innovate UK awarded Infleqtion £9 million to develop deployable Rydberg-atom radio direction-finding equipment with Leonardo, building on the QuDiFi prototype project. 00:0003:17 Infleqtion has won £9 million from Innovate UK to develop deployable quantum equipment for locating the direction of radio signals. The company announced the award on 13 October, with Leonardo collaborating on the project. The funding announcement covers the second phase of Quantum Direction Finding, or QuDiFi, within the Quantum Missions Primer programme. Infleqtion aims to build a Quantum Spectrum-DF product suited to realistic operating environments. The award takes a prototype towards field use. The next QuDiFi phase focuses on turning a tested prototype into robust equipment. Infleqtion describes work on performance, reliability, usability and validation in conditions representative of deployment. UKRI's November 2025 project announcement set out the earlier prototype programme under the lead name Coldquanta UK Limited. It covered sensor-head design, signal processing and integration with existing radio-frequency platforms, with a pathway towards smaller equipment and field trials. The new award continues that progression. A laboratory measurement can establish the sensing principle; a deployable product also has to keep working when its surroundings, platform and operator change. Highly excited atoms sense the radio field. Rydberg-atom sensors use atoms in highly excited states whose response to an electric field can be measured optically. Lasers probe the atomic response, providing information about an incoming radio signal. Radio direction-finding adds a spatial question: where is the signal coming from? A sensor can infer direction by comparing measurements taken at different positions or by analysing the field's pattern. A 2021 NIST demonstration measured the phase of a 19.18 GHz signal at two locations inside a caesium vapour cell. The phase difference allowed researchers to calculate its direction of arrival and compare it with a model. That earlier experiment illustrates the sensing principle behind this wider field of research. Compact sensors could fit on more platforms. Infleqtion aims to reduce the size of radio direction-finding equipment, particularly where conventional low-frequency systems require large antenna structures. Its proposed product uses optical measurements of atoms to support compact, broadband, passive sensing. That is relevant to platforms with limited space for antennas and associated electronics. The funded development will test whether the sensing approach can deliver useful performance in a practical package. The company's Quantum Spectrum product information describes its broader atomic radio-sensing approach. The new direction-finding project applies it to detecting and locating signals, with future applications including spectrum surveillance, passive radar and resilient navigation. Leonardo brings operational sensing requirements. Leonardo is collaborating with Infleqtion on the development programme. The award announcement includes Oliver Sims, Leonardo's electronic-warfare chief technologist, describing the potential to reduce the physical footprint of direction-finding systems. Innovate UK, part of UK Research and Innovation, is funding the work. The £9 million is an award for continued product development, with Infleqtion giving an approximate US-dollar equivalent of $12 million. The next test is whether the prototype's sensing capability can be retained in equipment that is reliable, usable and suited to its intended operating environment. That transition is the focus of the funded second phase.