System and method for wireless communication between several transceivers, arranged respectively in several delimited spaces, and portable electronic units
US6588661B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 2002 |
| Grant date | Jul 8, 2003 |
| Priority date | — |
| Expiry date | Feb 28, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/10356
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
System for communication between a plurality of transceivers, transmitting in particular at a high frequency and arranged respectively in a plurality of delimited spaces each having at least one entrance, and portable electronic units fitted with means for radio-communication with the plurality of transceivers, in particular with a view to detecting each of them penetrating one of the delimited spaces. The communication between the transceivers and the portable electronic units for neighboring delimited spaces is effected at different exclusive frequencies or frequencies of sub-sets of frequencies associated with the exclusive frequencies. In order to do this, devices for occupying an exclusive frequency are provided which include listening circuits (30, 32, 34, 36, 38, 46, 48) for determining whether an occupied signal is present on any frequency of a set of exclusive frequencies able to be selected and/or whether a determined amplitude threshold is received for this frequency, and transmission circuits (30, 52, 54, 56, 58) arranged to transmit an occupied signal in a selected exclusive frequency. This system thus prevents disturbances or interference between portable units locate…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.