Abstract: The invention relates to a method of determining the presence or otherwise in a zone of defined size around a master radio-communicating terminal, of a peripheral radio-communicating module, the radio-communicating terminal and module operating according to a radio communication protocol of BLUETOOTH® type and under the dependence of application programs, the protocol having means for retransmitting data from the module when the reception of said data by the terminal is incomplete or erroneous, this being so for a maximum re-try time, the data not being considered to have been received unless the reception of all the data is correct in the course of the maximum re-try time, the data exchanges being characterized by a transmission error rate.