Method for assisting in determining the position of an identifier in relation to a vehicle

Abstract

The invention relates to a method (METH) for assisting in determining the position of an identifier (I) for accessing and starting a vehicle (V), relative to the vehicle (V), comprising: transmission (Em_TS), from a first device, either the vehicle (V) or the identifier (I) to a second device, different from the first, either the vehicle (V) or the identifier (I), at a transmission time t0, of an initial train (TS) of N sinusoidal signals, having identical amplitudes and respective frequencies f, pϵ[1;N], for any p between 1 and N−1; reception (Rec_TS') by the second device of an image train (TS′) corresponding to the initial train (TS, TS) altered by the transmission (Em_TS); construction (Cons_Sp) of a frequency spectrum (Sp) for the image train (TS′); inverse Fourier transformation (TFI_Sp) of the spectrum (Sp), allowing a time signature (Sg) to be obtained; first integration (Int1_Sg) of the time signature (Sg), between the transmission time tand a pre-determined intermediate time t, producing a first result (Rlt1); second integration (Int2_Sg v) of the time signature (Sg) between the intermediate time tand a pre-determined end time t, producing a second result (Rlt2); comparison (Comp_1/2) of a ratio (R) of the first result (Rlt1) to the second result (Rlt2) with a threshold value (S), so that it is possible to determine if the identifier (I) is positioned inside the vehicle (V).