System and method for wireless communication between several transceivers, arranged respectively in several delimited spaces, and portable electronic units

摘要

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 said plurality of transceivers, in particular with a view to detecting each of them penetrating one of said delimited spaces. The communication between the transceivers and the portable electronic units for neighbouring delimited spaces is effected at different exclusive frequencies or frequencies of sub-sets of frequencies associated with said exclusive frequencies. In order to do this, means for occupying an exclusive frequency are provided which include listening means (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 means (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 located in a delimited space and a transceiver arranged in a neighbouring delimited space.