Owner Groundprobe Pty Ltd

Inventors Reeves, Bryan; Stickley, Glen

Agent Fisher Adams Kelly

Pub. Number AU-B-2006272449

PCT Pub. Number WO2007/009175

Priority 2005903785 18.07.05 AU

Filing date 18 July 2006

Wipo publication date 25 January 2007

Acceptance publication date 19 November 2009

G01S 13/89 (2006.01)

G01S 1/02 (2006.01) Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters

G01S 5/00 (2006.01) Position-fixing by co-ordinating two or more direction or position-line determinations

G01S 5/06 (2006.01) Position-fixing by co-ordinating two or more direction or position-line determinations - Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements

G01S 5/12 (2006.01) Position-fixing by co-ordinating two or more direction or position-line determinations - by co-ordinating position lines of different shape, e.g. hyperbolic, circular, elliptical or radial

G08B 21/02 (2006.01) Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for

G08B 21/18 (2006.01) Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for