Jindalee Operational Radar Network – Wikipedia

The Jindalee Operational Radar Network (JORN) is an over-the-horizon radar (OTHR) network that can monitor air and sea movements across 37,000 km 2.It has a normal operating range of 1,000 km to 3,000 km. It is used in the defence of Australia, and can also monitor maritime operations, wave heights and wind directions. JORN’s main ground stations comprise a control centre, known as JCC, at …

https://en.wikipedia.org/wiki/Jindalee_Operational_Radar_Network