Patent · US Expired

Personnel monitoring and locating system

US4495496A · kind A · utility

217Cited by
7References
25Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 15, 1981
Grant dateJan 22, 1985
Priority date
Expiry dateDec 15, 2001

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S379/913
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A personnel monitoring and locating system is disclosed that is particularly well suited for monitoring and/or locating underground miners. A plurality of remote terminals having transceivers associated therewith are positioned in a mine and periodically are caused to transmit interrogation signals. Each miner to be monitored is equipped with a transponder that replies to the interrogation signal with the reply signal being timewise delayed by a predetermined amount of time that is different for each of the transponders in use so that the reply from each transponder is timewise spaced from every other interrogated transponder. A host computer at the surface is linked to each remote terminal for transmission of information with information from the remote terminal being indicative of the location of each transponder equipped miner. The transponder carried by each miner is powered by the battery normally carried by the miner for powering a lamp, and the cord extending between the battery and the lamp is utilized by the transponder as a transmitting and receiving antenna.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.