CSIRO Builds Quantum Light Sources to Counter GPS Jamming and Spoofing

Insider Brief

• Commonwealth Scientific and Industrial Research Organisation (CSIRO) has developed portable quantum light sources designed to support secure time transfer by detecting interference with satellite-based navigation signals.
• The devices generate entangled photon pairs that could help provide alternative timing capabilities in environments where GNSS signals are disrupted by jamming or spoofing.
• The project, developed with Australia’s Defence Science and Technology Group, aims to support secure communications and timing applications across defence and civilian infrastructure.
• This report is based on materials from CSIRO, with additional reporting context from the Australian Defence Magazine and Phys.org.

GPS signals are weak by the time they reach Earth. That weakness is why they are increasingly being disrupted – blocked through jamming, or overridden with false signals through spoofing. GPS is the best-known satellite timing system in Australia and the United States, but it is one of several systems that together make up the Global Navigation Satellite System, or GNSS. Commonwealth Scientific and Industrial Research Organisation, Australia’s national science agency, has built two portable devices designed to replace those signals with something an attacker cannot convincingly fake.

In contested environments, satellite timing signals are being disrupted as an act of war. The consequences extend across military operations on air, land, sea, cyber, and space domains – and into civilian systems including power grids, financial services, transport networks, and emergency services that rely on the same signals for precise timing.

Jamming blocks the satellite signal so it cannot be received. Spoofing is more sophisticated – it transmits a false but convincing signal that tricks receivers into accepting the wrong time or location, according to Australian Defence Magazine. Both types of interference are growing concerns because conventional Global Navigation Satellite Systems (GNSS) signals are too weak to resist them.

What CSIRO Built

Commonwealth Scientific and Industrial Research Organisation (CSIRO) researchers developed two high-flux, portable, and deployable entangled photon sources as part of a project led by the Defence Science and Technology Group, according to Phys.org. The devices, which CSIRO calls the Quantum Light Source, generate pairs of light particles linked through quantum physics. One photon remains on the ground at an optical ground station while its entangled partner is transmitted to an orbiting satellite hundreds of kilometres away.

The quantum property that makes this useful for timing is the same one that makes it resistant to interference. Any attempt to intercept or tamper with the signal changes the quantum state, and that change is detectable instantly. According to CSIRO, users can then switch to a different channel. The process of continuous entanglement distribution is what the agency describes as making the system spoof-proof.

CSIRO Technical Lead Matt Broome described the result as “a significant milestone in the development of quantum-secure time transfer in Australia.”

The project began with a collaboration with Heriot-Watt University in Scotland, whose source design thinking CSIRO set out to translate from laboratory conditions into field-deployable hardware, source reported. The resulting devices are described as portable and easily deployable at optical ground stations.

Beyond Defence

While developed for the Australian Defence Force, CSIRO said the capability is not limited to military applications. The same secure timing that allows military systems to operate when GNSS is disrupted also applies to civilian infrastructure involving communications networks, power grids, transport, and financial services.

The project is also described as contributing to Australia’s sovereign capability in quantum components and secure communications – building know-how domestically in a technology area the agency says is likely to shape the future of secure communications, navigation, and timing.