a coaxial cable intended to be used in the field of telecommunications comprises a metal core surrounded by at least two layers one of which is a dielectric material layer and the other of which , disposed between the core and the dielectric material layer over at least part of the length of the cable , is a semiconductor composite material layer comprising an insulative matrix and an undoped polymeric conductor containing conjugate bonds . the cable features intrinsic filtering of electromagnetic interference conducted by the cable at frequencies below 1 ghz .