TRANSMITTER, RECEIVER, TRANSMISSION DEVICE, TRANSMISSION METHOD AND RECEPTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a transmission reception system where a problem of transmission information amount unable to be increased is solved and much information is transmitted at a same frequency band in the case that the frequency band is limited in the transmitter transmitting a digital signal. SOLUTION: A modulator 4 conducting m-value QAM modulation in a transmitter 1 transmits a modified m-value QAM modulation signal by assigning n-value data of a 1st data stream to a signal point group obtained by grouping signal points of the n-value 1st data stream, a p-value 2nd data stream and a 3rd data stream on a signal space diagram. A demodulator 25 of a 1st receiver 23 demodulates the n-value 1st data stream, a 2nd receiver 33 demodulates the 1st data stream and the 2nd data stream, and a 3rd receiver 43 demodulates the 1st data stream, the 2nd data stream arid the 3rd data stream so as to realize the transmission device that demodulates data of the n-value 1st data stream even by the receiver having demodulation capability for only the n-value of n