Jindalee Operational Radar Network

[1] The network is used in the defence of Australia, and can also monitor maritime operations, wave heights and wind directions.

In 1969, The Technical Cooperation Program membership and papers by John Strath prompted development of a core Over the Horizon radar project.

[3] From July 1970 a study was undertaken; this resulted in a proposal for a program to be carried out, in three phases, to develop an over-the-horizon-radar system.

[4][5] Phase 1, Project Geebung, aimed to define operational requirements for an OHR and study applicable technologies and techniques.

It involved the construction of a prototype radar receiver at Mount Everard, (near Alice Springs), a transmitter (at Harts Range, 160 kilometres or 99 miles away) and a beacon in Derby.

Developments during stage B included real time signal processing, custom built processors, larger antenna arrays, and higher power transmitters, which resulted in a more sensitive and capable radar.

Trials were carried out with the Royal Australian Air Force during April 1984, substantially fulfilling the mission of stage B, to demonstrate an OHR operating in Australia.

Telstra, in association with GEC-Marconi, became the prime contractor and a fixed price contract for the construction of the JORN was signed on 11 June 1991.

GEC-Marconi was responsible for the HF Radar and related software aspects of the project, areas in which it had no previous experience.

Subsequently, during June 1997 Lockheed and Tenix formed the company RLM Group to handle the joint venture.

During this period the Alice Springs radar had evolved significantly under the guidance of the Defence Science & Technology Organisation.

Phase 5 aimed to upgrade the Laverton and Longreach radars to reflect over a decade of OTHR research and development.

[citation needed] The ANAO Audit report of June 1996 estimated an overall project cost for Phase 3 of $1.1 billion.

The JORN transmitter and receiver sites are: The Alice Springs radar was the original 'Jindalee Stage B' test bed on which the design of the other two stations was based.

Intensive computational work is necessary to JORN's operation, and refinement of the software suite offers the most cost-effective path for improvements.

Officially the system allows the Australian Defence Force to observe air and sea activity north of Australia to distances up to 4,000 kilometres (2,500 mi).

[28] This encompasses all of Java, Irian Jaya, Papua New Guinea and the Solomon Islands, and may include Singapore.

JORN is so sensitive it is able to track planes as small as a Cessna 172 taking off and landing in East Timor 2,600 kilometres (1,600 mi) away.

[citation needed] Current research is anticipated to increase its sensitivity by a factor of ten beyond this level.