CSIRO Builds Portable Quantum Light Sources For Spoof-Proof Satellite Timing

Australia’s national science agency CSIRO has built two portable quantum light sources designed to secure ground-to-satellite timing when GPS signals are degraded, denied or at risk of spoofing.

The devices, developed as part of a Defence Science and Technology Group-led project, generate entangled photons that can maintain quantum correlations over large distances, providing a way to detect interference with timing signals in real time.

The work is aimed at demonstrating a quantum-secured timing network for the Australian Defence Force, but CSIRO says the same technology has applications across civilian infrastructure including communications, power grids, transport and financial services.

Why timing matters

Modern defence systems and civilian infrastructure rely on precise timing signals from satellites. The Global Navigation Satellite System (GNSS) uses satellites carrying atomic clocks to transmit time-stamped signals to receivers on Earth. The Global Positioning System (GPS) is the most widely used GNSS in Australia and the United States, but it is one of several systems operating globally.

Those signals underpin navigation and keep networks running. They are also increasingly being targeted.

GNSS interference takes two main forms. Jamming blocks satellite signals so they cannot be received. Spoofing is more sophisticated, sending a false signal that tricks a receiver into accepting the wrong location or time.

Both are illegal in Australia and many other countries, but jamming devices are still accessed through illicit channels. Spoofing capability is harder to obtain, though the risk is growing as software-defined radio, open-source tools and technical knowledge become more accessible.

CSIRO says the threat is no longer theoretical. In contested environments, GNSS signals are being disrupted as an act of war, causing systems across air, land, sea, cyber and space to fail.

How the quantum light source works

The CSIRO Quantum Light Source generates tiny particles of light that are linked through quantum physics, a phenomenon known as quantum entanglement. Two photon particles become linked so that a change to one is instantly reflected in the other, regardless of distance.

In practice, one photon stays on Earth while its entangled partner is sent to an orbiting satellite hundreds of kilometres away. Despite the separation, the photons remain entangled and a secure communication link can be established.

The approach is useful for ground-to-satellite time transfer because entanglement is sensitive to interference. If someone attempts to intercept or tamper with the signal, the quantum state changes and the disruption is detected instantly, allowing the user to switch to a different channel.

This process, known as entanglement distribution, can run continuously to maintain a secure link. CSIRO says it is what makes the quantum light source resistant to spoofing.

The agency initially collaborated with Heriot Watt University, with the CSIRO team working to take the Scottish university’s source design from the lab into a field-ready form.

A path to sovereign capability

CSIRO Technical Lead Dr Matt Broome described the project as a step forward for Australian quantum capability.

“This work is a significant milestone in the development of quantum-secure time transfer in Australia,” Broome said.

“With this work, CSIRO has developed specialised capability, which puts Australia on the path to a more resilient future in global positioning technology.”

The two devices are designed to be portable and deployable to optical ground stations, moving the technology closer to field use rather than remaining a laboratory demonstration.

Beyond defence

While the project is being developed for defence, CSIRO says the need extends well beyond military applications.

The same secure timing that helps military systems operate when GNSS is disrupted also protects civilian systems including communications networks, power grids, transport and financial services.

For Australia, CSIRO frames the project as a demonstration of how research can be translated into practical technology. By developing quantum components domestically, the agency says it is building sovereign knowledge in an area likely to shape the future of secure communications, navigation and timing.

Last Updated on July 6, 2026 by Nick Ross