| 摘要 |
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. The read device includes detection means which are configured to reduce the noise or the fluctuations, in the signal from the antenna, which are due to the electronic components of the power stage, and to generate a useful signal from the change in the signal from the read antenna by comparison with a reference signal, this reference signal being representative of the signal from the read antenna when the receiving antenna of the transponder is in a predetermined state, the useful signal being representative of the changes of state of the receiving antenna. |
