Patent ID: 11885867
Assignee: CONTINENTAL AUTOMOTIVE GMBH
Field: Measurement (Instruments)
Classification: CPC G  B | IPC B  G

Claim 6:
7. A computer intended to be mounted in a motor vehicle in order to determine the distance between an authentication device intended to be carried by a user and said vehicle, said device and said vehicle each comprising a wireless communication module allowing at least one data frame to be exchanged between the communication module, denoted transmitter, of the device and the communication module, denoted receiver, of the vehicle, said data frame comprising a series of bits with a value of 0 or 1 modulated by the transmitter by changing the phase of a reference signal comprising a component, called “in-phase” component, characterized by a maximum amplitude value, and a second component, called “quadrature” component, phase-shifted by 90° in relation to the in-phase component and characterized by a maximum amplitude value, the receiver being configured to receive a modulated reference signal, which signal is sent by the transmitter and the phase changes of which characterize the values of the bits of a data frame, and to demodulate the received reference signal in order to extract the in-phase component and the quadrature component therefrom, the computer being configured to compute the power value (PdBm) of the reference signal on the basis of the maximum amplitude value of the in-phase component and of the maximum amplitude value of the quadrature component and to determine the distance between the transmitter and the receiver on the basis of the computed power value.