Process for secure access to a determined space equipped with an access or unlocking device by means of a customised wearable object through a wireless signal communication, wherein the access or unlocking device comprises a transmitter of radiofrequency signals at high frequency, a receiver of radiofrequency signals at high frequency, a processing unit and a local oscillator for clocking the operations of the access or unlocking device, and the wearable object comprises a transmitter of radiofrequency signals at high frequency, a receiver of radiofrequency signals at high frequency, a processing unit and a local oscillator for clocking the operations of the wearable object, wherein the process is characterised in that it comprises the steps of: - activating the wearable object, - transmitting a first coded signal from the access or unlocking device, - receiving the first coded signal from the access or unlocking device in the wearable object to demodulate the code by defining time and preparing a coded response signal, in order to transmit this coded response signal with synchronisation to the access or unlocking device after a defined time of transmission (T F) following initiation and as of the transmission of the first coded signal in the access or unlocking device and obtained by time counting following reception of the first coded signal and thanks to the local oscillator in the wearable object similar to that one of the device, - receiving the coded response signal from the wearable object in the access or unlocking device, - processing the converted coded response signal in the processing unit of the access or unlocking device, by checking the defined time delay and the response code of the wearable object, in order to determine the flight times of the signals between the access or unlocking device and the wearable object and deducing therefrom the distance separating the wearable object and the access or unlocking device, to authorise access to the determined space, if the calculated distance is below a determined threshold after recognition of the wearable object. - activating the wearable object, - transmitting a first coded signal from the access or unlocking device, - receiving the first coded signal from the access or unlocking device in the wearable object to demodulate the code by defining time and preparing a coded response signal, in order to transmit this coded response signal with synchronisation to the access or unlocking device after a defined time of transmission (T F) following initiation and as of the transmission of the first coded signal in the access or unlocking device and obtained by time counting following reception of the first coded signal and thanks to the local oscillator in the wearable object similar to that one of the device, - receiving the coded response signal from the wearable object in the access or unlocking device, - processing the converted coded response signal in the processing unit of the access or unlocking device, by checking the defined time delay and the response code of the wearable object, in order to determine the flight times of the signals between the access or unlocking device and the wearable object and deducing therefrom the distance separating the wearable object and the access or unlocking device, to authorise access to the determined space, if the calculated distance is below a determined threshold after recognition of the wearable object.