Jindalee Operational Radar Network
The Jindalee Operational Radar Network (JORN) is an over-the-horizon radar (OHR) network operated by the Royal Australian Air Force (RAAF) that can monitor air and sea movements across 37,000 square kilometres (14,000 sq mi). It has a normal operating range of 1,000–3,000 kilometres (620–1,860 mi).
Source: Wikipedia — Jindalee Operational Radar Network (CC BY-SA 4.0)