Locating the Source of Long-Distance Radio Distress Signals from the Southern Ocean

• Main Author: Goodwin, G. L.
• Other Authors: ELECTRONICS RESEARCH LAB ADELAIDE (AUSTRALIA)
• Format: Text
• Language: English
• Published: 1988
• Subjects: Direction Finding; Escape; Rescue and Survival; *RADIO SIGNALS; *SEARCH AND RESCUE; *DISTRESS SIGNALS; RESCUES; FEASIBILITY STUDIES; LONG RANGE(DISTANCE); OCEANS; DOPPLER SYSTEMS; AUSTRALIA; SOUTH(DIRECTION); TROUGHS; REAL TIME; AIRCRAFT; IONOSPHERE; POSITION(LOCATION); Southern Ocean
• Online Access: http://www.dtic.mil/docs/citations/ADA198239; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA198239

This report summarizes a feasibility study and strategy appropriate to search and rescue operations for ships or aircraft in distress in the Southern Ocean. The use of high frequency ionospherically-propagated radio transmissions is justified. Measurement of the direction of arrival of a radio signal facilitates ray-tracing through the ionosphere Characteristics of the F2 region mid-latitude ionization trough are considered in detail. Because the trough is displaced towards Australia, its position must be known as near as practicable in real time for sufficiently accurate ray-tracing to be performed quickly enough after receipt of a distress signal. The differential Doppler technique using e.g. 150 and 400 MHz transmissions from NAVSAT (NNSS) satellites is recommended in locating the trough position.