Abstract: In a system and method of transmitting information over metal wire, a plurality of base band encoded frequencies are combined to create a single complex, modulated signal that will produce a desired throughput. The various digital signals are encoded using phase shifting to represent logic changes. At the receiver, the signals are separated and each signal is decoded by considering several sidebands for each baseband signal, covering 180° of phase. Synchronicity is ensured by transmitting a pilot frequency.

Abstract: A process for transmitting a stream of digital data over a high impedance metallic pair transmission line under high loss conditions is disclosed. This process involves first converting the digital data into a stream of binary code. The first element of the code has a bit cell voltage-time wave shape that begins at 0 volts, moves sharply to an initial voltage A different than zero, at mid cell traverses 0 volts to a second voltage B of similar magnitude but opposite sign to the initial voltage A and that returns to zero at the end of the bit cell. The wave shape has a duty cycle of 80% or greater. The second element of said code is a mirror image of the first element. This code is applied to one end of the transmission line. the stream of binary code is then detected at the other end of the transmission line and reformatted to digital data.