Communication device with an inductive antenna

The device has an inductive antenna (1) connected with a signal generator (5). A conductive cable (2) is coupled with the antenna along the entire contour of the antenna such that the cable presents inductive coupling with the inductive antenna. The cable has two ends connected to respective terminals of a switch (3) connected with a control module (6) for modifying selectively an internal impedance of the cable. Independent claims are also included for the following: (A) a communication device intended to be embarked in a vehicle and comprising a signal generator connected to an inductive antenna for emitting a radio frequency signal; and (B) a radiofrequency communication method.