The Fremantle (FRE) HF ocean radar site (32.031 S, 115.746 E) is one of two HF ocean radars covering Rottnest Shelf and Perth Canyon off the coast north of Perth. The other HF ocean radar station is at Guilderton. The HF ocean radar coverage is from the coast to beyond the edge of the continental shelf.
The FRE HF ocean radar is a WERA phased array system with a 16-element receive array. This radar operates at a frequency of 8.512 MHz, with a bandwidth of 33 KHz, a maximum range of 200 Km and a range resolution of 4.5 Km. Azimuthally the radar covers a sweep 60 deg either side of a bore sight direction of 285 deg true east of north (approximately west by north-west).
Within the HF radar coverage area surface current radials are measured. Data are also collected from which wind directions and significant wave height can be calculated.