System and method for initiating communications between a controller and a selected subset of multiple transponders in a common RF field
US5434572A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 7, 1994 |
| Grant date | Jul 18, 1995 |
| Priority date | — |
| Expiry date | Jun 7, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S13/825
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system and method for initiating communication between a controller and a selected one or other subset of multiple transponders in a common RF field in which each transponder has a unique, (or commonly unique) preprogrammed ID number. The controller transmits a series of commands/questions to the transponders and they either respond, or do not respond, to the controller based on their ID number, with the non-responding transponders entering a reset state. The transponders respond to the controller in such a way that, if multiple transponders respond, the controller can recognize that at least one transponder has responded and, for individual responses, the controller is not required to determine how many transponders have responded. Through use of the communications system and method disclosed, a sequence of controller commands and transponder responses single out a selected individual transponder or group of transponders based upon its particular ID number.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.