A system and method for communicating an electrical signal from a first region to a second region via an electrically conductive wall between the first and second regions. The method comprises using a transmitter to generate the signal in the first region, using the wall or a segment of the wall as part of a transmission path for the signal between the first region and the second region, wherein the transmitter comprises an output impedance and means for matching the output impedance and an impedance of the wall determined by an electrical property of the wall. The system comprises a first region separated from a second region by means of an electrically conductive wall, wherein the first region comprises a transmitter for generating an electronic signal in the first region, which transmitter has an output impedance that matches an impedance of the wall.