The USA is to test Australian-developed over-the-horizon radar (OTHR) technology late this year under a joint project to detect boost-phase ballistic missiles launched from the continental USA. It is unclear whether the US missile launches will be monitored using the Australian-based Jindalee operational over-the-horizon radar network (JORN) or Australian-developed technology to be integrated with current US systems.

The most likely technology application available from Australia would be analogue detect and track software and underlying source- code algorithms developed for Australia's prototype OTHR radar at Alice Springs. If the JORN network is used, the trial would represent the first confirmation that the radar has an effective range of at least 12,000km (6,490nm), rather than the 3,000km now cited.

The control workstations for the JORN HF backscatter sounding system, which measures the condition of the ionosphere separately to the main radar tracking system, display meaningful signal returns from distances of up to 12,300km. The US West Coast missile range at Vandenberg AFB, California is about 12,000km from the JORN R1 array at Longreach in central Queensland. If the main radar performance matches this capability, direct monitoring of launches from Vandenberg should be possible using the existing R1 array.

Based on that scenario, Australia's current three-radar OTHR system would already be capable of detecting and tracking air targets in an arc that covers most of eastern Russia, all of China, all of India and west Asia up to the Red Sea.

Defence minister Robert Hill says Australia conducted trials of the JORN system in boost-phase detection last April using a manned aircraft as a missile surrogate. These were intended to detect the target and provide additional information about its trajectory by using "multiple receiving systems".

Australia's Defence Science and Technology Organisation has previously undertaken initial exploration of sensor picture fusion between data from the US Space Command's Defence Support Programme infrared early warning satellite system and JORN track data.



Source: Flight International