Abstract: Read device (100) including a power stage and a read antenna (110) making it possible to generate an electromagnetic field for excitation of at least one transponder (10) situated in the field of the antenna, this transponder including a receiving antenna (11) and associated changeover-switching means (12) allowing it to modify the state of the receiving antenna and thus to transmit information to the read device, by modification of the coupling between the read antenna and the receiving antenna.

Abstract: A method and apparatus for simultaneously storing a set of read/write or respond-to-order transponders located in a container. The method transmits radiation to read/write trnsponders to energize them, receives identity data transmitted by the transponders, verifies that the identity data are not subject to dispersion, transmits a data group to the transponders, and stores the data group in memories of the transponders. If the identity data are subject to dispersion, the method interrupts radiation transmission in order to deactivate the transponders and then retransmits the radiation until the data are not subject to dispersion so that the data group can be transmitted to the transponders for storage in their memories. In the case of respond-to-order transponders, a signal is also transmitted. If the identity data are subject to dispersion, the signal is retransmitted until the data are not subject to dispersion, and then the data group is transmitted to the transponders and stored in their memories.

Abstract: A solar-powered beacon comprises a water-tight caisson housing a battery for storing electricity produced by solar cells atop the beacon. An electronic circuit within the caisson controls operation of the beacon. The caisson material acts as a heat sink for the solar cells, and insulation is provided below the cells to further protect the electronic components.