Emergency Location -- Delivering Portability & Precision

Abstract

The advent of Search & Rescue Satellite-Aided Tracking (SARSAT) in the mid-1980's saw the launch of a new and radically different international distress signal centred around 406 MHz. The 406 MHz waveform was quite different from the traditional 121.5 MHz distress frequency not least because it was encoded with digital data which uniquely identified the beacon and its country of registration. In addition, the 406 data message included provision for encoding position co-ordinates using location protocols. For installed marine or aircraft emergency transmitters, the position co-ordinates were typically derived from on-board navigation equipment such as GPS. The challenge, however, was to integrate 406 MHz location functionality in a manportable Personal Locator Beacon (PLB) while still keeping weight and size to a practicable level that facilitated carriage in a standard aircrew life-vest. In addition, the 406 data message created the opportunity to enhance the capability of SAR homing systems by decoding and displaying message information including GPS-derived latitude and longitude. The aim of this paper is to outline the developments in SAR Satellite Aided Tracking and to discuss recent developments in SAR emergency beacons and associated airborne detection and tracking systems.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 2004
Accession Number
ADA446515

Entities

People

  • Barry Thrower

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Air Force
  • Aircrafts
  • Artificial Satellites
  • Decoding
  • Distress Signals
  • Earth Orbits
  • Ejection Seats
  • Emergencies
  • Frequency
  • Geosynchronous Orbits
  • Geosynchronous Satellites
  • Latitude
  • Low Earth Orbits
  • Precision
  • Radiation Patterns
  • Search And Rescue
  • Standards

Readers

  • Maritime Security/Maritime Homeland Security
  • Radio communications and signal processing.
  • Systems Analysis and Design

Technology Areas

  • Space
  • Space - Space Objects