Multi-level modulation apparatus, multi-level demodulation apparatus, multi-level modulation/demodulation communication system, program and modulation/demodulation method

摘要

In a QAM modulation system, (3p+1) or (3p+2) input signal strings, where p is an integer not less than 3 or 2, are converted into three (p+1) string signals which are then allocated to three phase planes. The converted three (p+1) string signals are time-division multiplexed and multi-level modulated to realize QAM modulation in which the n-ary number may be set to approximately 2^(p+1/3) or 2^(p+2/3). In a QAM modulation system, (4p+3) input signal strings, where p is an integer not less than 3, are converted into three (p+1) string signals, which are then allocated to three phase planes, time-division multiplexed and multi-level modulated to realize QAM modulation in which the n-ary number may be set to approximately 2^(p+3/4).