Evolution of Over-the-Horizon Radar in Australia From Humble Origins to Operational Capabilities

The successful realization of high frequency (HF) over-the-horizon radar (OTHR) is one of the more significant radar developments since World War II. The first project to develop OTHR in Australia commenced in 1974 and was called Jindalee. The operational outcome of that project carries this iconic name in the Jindalee Operational Radar Network (JORN). JORN consists of three operational OTHR systems that deliver wide-area surveillance over Australia's northern approaches as a key element of an integrated defense surveillance system. JORN is one of Australia's quietest achievers and is widely recognized in a global sense as the frontier of OTHR capability. The now Defence Science and Technology Group pioneered the development of OTHR in Australia from humble origins in the 1960s and continues to lead innovation in HF radar systems to the present day. This article reviews the evolution of OTHR in Australia including the most recent phases of JORN. Through the lens of JORN as an exemplar Australian program, it reflects on pivotal factors contributing to the successful transition of use-inspired scientific innovation to defense operational capability.