This contribution has been developed in the following of previous work realised in the laboratory. The objective is to design a smart and reliable identification system of buried pipelines without excavation. For this purpose, a teledectectable code must be inserted into the existing coloured alarm net commonly used for public works. In this thesis, a magnetic materiel is used and studied to conceive the code. Its main advantage is that it has a very high magnetic permeability. In the device developed in the laboratory, it is detectable at more than one meter deep. Its response is non-linear,...