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.