A wired drill pipe for a drill string of a downhole tool positioned in a wellbore penetrating a subterranean formation is provided. The wired drill pipe includes a drill pipe, a cable and a wire retainer. The drill pipe has a slot at each end thereof. The slots are adapted to receive at least one transformer....http://www.google.de/patents/US7777644?utm_source=gb-gplus-sharePatent US7777644 - Method and conduit for transmitting signals
