System and process for determining at least one parameter of at least one rotating member by means of reference and speed signals

The system has a sensor (6) and a detection device (4) coupled to a frame. A speed measuring unit measures rotation speed of a rotating unit. An activation device (7) is connected to the sensor and the detection device, and activates the detection device at an indexed position of the transponder, such that the transponder is in a transmission / reception cone of the communication of the detection device. Independent claims are also included for the following: (A) a process of determining a parameter of a rotating unit with respect to a frame (B) a motor vehicle including a system for determining a parameter of a rotation unit of a vehicle.