Alternatives to GPS are around the corner

GNSS jamming is increasingly common in war and could disrupt a continent; research led by Todd Humphreys has linked broad European interference since 2019 to Russian satellites. Camera terrain navigation fails over sea or in cloud, haze and darkness. Two alternatives look credible. Magnetic navigation uses crustal anomalies: Q-CTRL’s optically pumped rubidium magnetometer beat a leading GPS alternative in an Australian trial; SBQuantum’s nitrogen-vacancy diamond magnetometer also measures direction for vector maps. The bottleneck is accurate crustal maps—SBQuantum surveys and SandboxAQ proposes a global effort, encouraged by US quantum-sensing research orders. Signals-of-opportunity systems infer position from other satellites’ radios. ASPIN Lab’s Matrix used Doppler from 21 Starlink and OneWeb satellites to locate a cruise ship near Greenland within 27 metres; manoeuvres can cause 100m–1km+ errors, but SpaceX publishes accurate orbit predictions for its 11,000-plus satellites. Corrections and multi-satellite ranging could target ~10m or even ~2m. Matrix has also used mobile-tower signals for aircraft and is licensed to commercial and military users, with market readiness expected within about two years.