METHOD FOR ACTIVATING A FUNCTION OF A VEHICLE BY ULTRA HIGH FREQUENCY WITH AN ITEM OF PORTABLE USER EQUIPMENT AND DEVICE FOR ACTIVATING AN ASSOCIATED FUNCTION

A UHF communication method for activating a motor vehicle function with a portable item of user equipment, based on the presence of the portable item of equipment in predetermined areas around the vehicle. The portable item transmitting a first signaling event at a predetermined period on at least one signaling channel. The first event including at least one signaling frame having a data block. The method including: a predetermined number of additional signaling events transmitted to the vehicle during the period; a request signal received from the vehicle, for each signaling frame of each event received by the vehicle; sending a response frame upon receipt of the request signal by the portable item; determining the presence of the portable item in one of the predetermined areas based on the strength values of the received signal; activating a vehicle function based on the determined presence of the portable item of equipment.