System and method for wireless communication between several transceivers, arranged respectively in several delimited spaces, and portable electronic units
First Claim
1. A system for communication between a plurality of transceivers, 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 these electronic units which penetrates one of said delimited spaces, wherein said transceivers and said electronic units are arranged to be able to communicate, among a set of given frequencies and/or frequency sub-sets respectively associated with said frequencies, at any frequency and/or frequencies of an associated sub-set of frequencies, each of said transceivers being associated with means for occupying a frequency exclusive thereto, said transceivers including:
- listening means arranged to determine whether an occupied signal is present on any frequency among said set of frequencies and/or whether a given amplitude threshold is exceeded upon reception of said frequency;
transmission means arranged to transmit at any frequency of said set of frequencies; and
means for selecting, in a period prior to a period of communication with electronic units, an exclusive frequency among said set of frequencies which does not contain an occupied signal or whose received amplitude level is less than said threshold;
said transmission means transmitting at the selected exclusive frequency an occupied signal for said exclusive frequency at least periodically during at least said communication period, this system having means for communicating information relative to said exclusive frequency to the portable units entering and/or exiting and/or located in the delimited space inside which the transceiver being considered is arranged.
1 Assignment
0 Petitions
Accused Products
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 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.
8 Citations
14 Claims
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1. A system for communication between a plurality of transceivers, 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 these electronic units which penetrates one of said delimited spaces, wherein said transceivers and said electronic units are arranged to be able to communicate, among a set of given frequencies and/or frequency sub-sets respectively associated with said frequencies, at any frequency and/or frequencies of an associated sub-set of frequencies, each of said transceivers being associated with means for occupying a frequency exclusive thereto, said transceivers including:
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listening means arranged to determine whether an occupied signal is present on any frequency among said set of frequencies and/or whether a given amplitude threshold is exceeded upon reception of said frequency;
transmission means arranged to transmit at any frequency of said set of frequencies; and
means for selecting, in a period prior to a period of communication with electronic units, an exclusive frequency among said set of frequencies which does not contain an occupied signal or whose received amplitude level is less than said threshold;
said transmission means transmitting at the selected exclusive frequency an occupied signal for said exclusive frequency at least periodically during at least said communication period, this system having means for communicating information relative to said exclusive frequency to the portable units entering and/or exiting and/or located in the delimited space inside which the transceiver being considered is arranged. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A method of communication between transceivers, arranged respectively in delimited spaces next to each other or capable of being so at least temporarily and portable electronic units fitted with radio-communication means and capable of penetrating these delimited spaces, said transceivers and said electronic units being arranged to allow high frequency communication, among a set of given frequencies and/or sub-sets of frequencies respectively associated with said frequencies, at any frequency and/or frequencies of an associated sub-set of frequencies, this method having, for each transceiver, the following steps in a period prior to a high frequency communication period:
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listening at a first frequency of said set of frequencies to determine whether an occupied signal is present on this first frequency and/or whether a given amplitude threshold is exceeded for this first frequency;
changing channel to listen at another frequency of said set of frequencies to determine whether an occupied signal is received on said first frequency or whether the amplitude level received for this first frequency is greater than said threshold;
until a frequency is available, which is then selected as the exclusive frequency, this method further including the following steps;
sending an occupied signal for said selected exclusive frequency, so that it is not subsequently taken by transceivers arranged in neighbouring delimited spaces, at least during a subsequent period of communication at the selected exclusive frequency and/or at a frequency of said sub-set of frequencies associated with this exclusive frequency;
communicating, to the electronic units entering and/or exiting and/or located in the delimited space being considered, information relative to the exclusive frequency selected for a high frequency communication. - View Dependent Claims (9, 10, 11, 12, 13, 14)
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Specification