Patent ID: 8019572

Claim:
A method of exploring by wave propagation, which method comprises: (a) a measurement step including a plurality of emissions (a1) during which a set of transducers i are caused to emit incident waves into a diffusing medium, and a plurality of receptions (a2) during which the set of transducers are caused to pick up signals representative of the waves reverberated by the medium from each incident wave; and (b) a processing step during which the picked-up signals are processed; wherein, during the processing step, consideration is given to a plurality of sets k of reverberated signals B k (i, t), each of which comes substantially from a point r k belonging to the same isoplanatic zone ZI(r 0 ) that is common to said sets k of signals and that itself relatives to a point r 0 of the medium, the points r k being either different from one another regardless of the medium, or coinciding with the point r 0 when the medium includes diffusers having random motion; wherein the reverberated signals B k (i, t) of the sets k are re-positioned in time if the points r k are different from one another in order to obtain corrected signals B0 k (i, t)=B k (i, t−G i (r k )), where the values G i (r k ) are delays such that, by causing the transducers i to emit signals e k (i, t)=e 0 (i, t+G i (r k )), the incident wave focuses substantially at the point r k , the signals e 0 (i, t) being reference signals such that, by causing the transducers i to emit said reference signals e 0 (i, t), the incident wave focuses substantially at the point r 0 ; and wherein the signals B0 k (i, t)=B k (i, t−G i (r k )) are put into phase and averaged so as to obtain average signals Bf ⁡ ( i , t ) = ∑ k ⁢ A k ⁢ B ⁢ ⁢ 0 k ⁢ ( i , t - c k ) where the values c k are delays making it possible to put the signals B0 k into phase, and the values A k are weighting coefficients.