Intelligent locator system with multiple bits represented in each pulse
US5426425A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 7, 1992 |
| Grant date | Jun 20, 1995 |
| Priority date | — |
| Expiry date | Oct 7, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B3/1083
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A locating and monitoring system includes transmitters worn by a person, animal, or equipment to transmit an unique identification code while moving about a facility. The code is transmitted by pulse bursts at diverse times during predetermined time intervals to prevent synchronization with resident signals in the facility. Receivers in the walls or ceilings of the facility respond to the infrared radiation of the pulse bursts and validate the identification code by a checksum of the code through a comparison with a checksum transmitted with the code. The receivers deliver validated codes to arbitrators and receive back signals indicative of the level of an individual assigned to a class wearing the transmitters. Signals from the receivers are received by arbitrators which forward the codes to a CPU for recording start and stop events indicative of movement by transmitters into and out of the reception range of the various receivers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.