Tag location monitor
US5742237A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 30, 1995 |
| Grant date | Apr 21, 1998 |
| Priority date | — |
| Expiry date | Nov 30, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/2482
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A monitor network of a tag location system includes a grid of monitors for transmitting and receiving messages from neighboring monitors and tags within range of the monitor. Also provided is a memory device for storing: a unique identity of the monitor; each input partner monitor from which the monitor receives messages, and an output partner monitor to which the monitor sends messages; monitor and tag signals; a signal strength of the tag signals and significant changes thereto; an acknowledgement signal; and a distress signal indicating that the monitor has not received acknowledgement signal from its output partner monitor. Further there is a computer for periodically causing all tag signals, associated signal strengths and significant changes stored in the memory device to be transmitted to the output partner monitor, for forwarding received monitor messages to the output partner monitor, for issuing the acknowledgement message to be transmitted of a monitor message, for determining receipt of an acknowledgement and for sending a distress signal to all neighboring monitors within range of the monitor if an acknowledgement signal is not received from the output partner monitor.…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.