Noise modulated remote distance measurement

摘要

The invention relates to remote distance measurement by means of a transmitted noise modulated probing signal (E), whereby at least one of a distance (Y(t)) and a velocity (V(t)) in relation to a signal transceiver ( 200 ) is determined. The probing of signal (E) is generated on basis of at least one first noise signal (x₁(t), x₂(t)). The transmitted signal (E) is presumed to be reflected to the signal transceiver ( 200 ) via at least one signal reflecting object in the form of an information carrying signal (e). This signal thus constitutes a delayed and possibly doppler shifted version of the transmitted signal (E). Moreover, according to the invention, a second noise signal (x₂(t)) is added either to the probing signal (E) before it is transmitted or to the information carrying signal (e) before information pertaining to the reflecting object is derived there from. A primary signal (P₁(x₁)) is generated, which is based on the first noise signal (x₁(t)) and a secondary signal (P₂(x₁, x₂)) is generated, which is based on the information carrying signal (e). Thanks to the contribution from the second noise signal (x₂(t)) the subsequent signal processing of the primary signal (P₁(x₁) and the secondary signal (P₂(x₁, x₂)) can be performed with a high linearity at the same time as a comparatively simple equipment can be can be utilized for digitizing ( 240 ) signal components (S_I, S_Q; R_I, R_Q), which have been demodulated from the primary signal (P₁(x₁)) and the secondary signal (P₂(x₁, x₂)) respectively. The solution according to the invention is also applicable at remote distance measurement by means of a digital group antenna system.