Engineering topics

Trudell, B.

Publications and source records attributed to Trudell, B..

3 records

NASA NTRS1984

SARSAT - Using space for the search and rescue of lives in distress

A major cooperative effort between west and east bloc nations in developing a new space system for detecting ships and aircraft in distress is discussed. The compatible working of the SARSAT system developed by Canada, France, and the US and the COSPAS system developed by the Soviet bloc is summarized, and the SARSAT system is described. The method of location determination is presented, and the ELT and EPIRB, space segment, local user terminal, and mission control center subsystems of the SARSAT system are surveyed, showing block diagrams and data on spacecraft orbital parameters and ELT/EPIRB BECON characteristics. The current problem of ground-based interference is discussed. An outline of future development activities leading to the implementation of a fully operational system is included.

Flatow, F.↗

NASA NTRS1982

Use of a geosynchronous satellite within the SARSAT/COSPAS system

Operational characteristics of combined LEO SARSAT/COSPAS and GEO spacecraft for localization of aircraft and seacraft emitting distress signals are described. Although 121.5 MHz capability is now included in all SARSAT/COSPAS satellites, limitations on the number of simultaneous signals which can be processed at that frequency due to atmospheric noise indicates the employment of the 406 MHz band. Additionally, the necessity for on-board storage for later transmission when the satellites are in a favorable position is leading to the implementation of GEO stationed relays for real-time transmission and processing of distress signals. Six NOAA spacecraft and two Soviet satellites are planned, with a completed system offering high detection probability, position location, worldwide coverage, coded messages, and high capacity (406 MHz). A significant factor in use of a GEO relay system is noted to be the signal to noise temperature of the repeater.

Goudy, P.↗

NASA NTRS1980

Search and rescue satellite-aided tracking system

The objective of Sarsat is to demonstrate that satellites can greatly facilitate the monitoring, detection, and location of distress incidents alerted by Emergency Locator Transmitters (ELTs) and Emergency Position Indicating Radio Beacons (EPIRBs) carried on commercial, military, and general aviation aircraft and some marine vessels. The detection and location will be accomplished by relaying, via satellite, ELT/EPIRB distress information to ground stations, which will complete the data processing and forward alert and position location data to rescue coordination services. This paper presents a Sarsat system description and a summary of Coast Guard and USAF objectives for the initial demonstration and evaluation tests of Sarsat.

Trudell, B.↗