A first component (CMP1) is connected to the antenna (ANT) and to an impedance matching circuit (CAI) configurable on command and connected to the antenna, and in the absence of another component (CMP2) connected to the antenna, the impedance matching circuit is placed in a first configuration in which it forms with the first component and the antenna a resonant circuit having a first resonant frequency compatible with a carrier frequency. In the presence of a second component (CMP2) connected to the antenna, the impedance matching circuit is placed in a second configuration in which it forms with the first component, the second component and the antenna a resonant circuit having a second resonant frequency compatible with the carrier frequency.