| 摘要 |
The invention relates to a contactless portable object (10, 30, 60) comprising a main radiofrequency device composed of a main chip (18, 38, 68) and of a main antenna (16, 36, 66) that are connected together so that when the portable object enters the magnetic field of a suitable reader, the main radiofrequency device ensures the powering of the chip and the communication between the chip and the reader. According to the main characteristic of the invention, the portable object comprises a secondary contactless device comprising a secondary antenna (12, 32, 62) and an electrical circuit that are parameterized in such a way that, when the two antennas enter the magnetic field of a suitable reader at the same time, the quantity of energy required to power the electrical circuit so as to make it operate being less than the quantity of energy required to power the main chip (18, 38, 68) so as to make it operate, the electrical circuit is powered and makes it impossible to read the data of the main chip. |
