System for transmitting information codes with multi-level modulation scheme and a modulation apparatus

摘要

A transmission system for transmitting information codes by using a multi-level modulation scheme has a transmitter and a receiver. The transmitter has a divider circuit for dividing inputted N-bit information data stream into M (M is integer not less than 2) data stream; an error correction coding circuit for individually converting the M streams into error correcting code streams so as to deliver M error correcting code streams; a multi-level modulation circuit for making the correspondence between data streams of N bits constituted by the M error correcting code streams and a plurality of signal points arranged on a signal constellation and modulating two carriers with coordinate values of signal points on the signal constellation corresponding to the N-bit code stream; and a high frequency circuit unit for outputting a modulated signal in a radio frequency to a transmission antenna.