| 摘要 |
PURPOSE:To improve the efficiency of transmission power in the transmission data of a multilevel QAM by converting the multilevel QAM transmission data to signal point arrangement which is almost circular by a transmission part, after that, using addition logic, using subtraction logic concerning a received signal by a reception part, after that, executing conversion reverse to the transmission side. CONSTITUTION:In the case of a 512 QAM differential logical communication system, namely, when the signal point arrangement is expressed by 29, a transmission side convertion circuit 1 executes the bit conversion to a circular area B in a signal point arrangement plane A of a 1024 QAM equipped with a high-order bit arrangement. A transmission side addition logic circuit 2 obtains the addition logic concerning a multilevel QAM transmission signal to which the signal point arrangement is converted in such a manner. A reception side differential logic circuit 6 obtains the differential logic reverse to the transmission side addition logic circuit 2 concerning the reception signal. After that, since the multilevel QAM converted in the transmission side is restored to the former 512 QAM transmission data of the transmission side conversion circuit 1 by a reception side conversion circuit 7, the signal point arrangement is converted reversely to the transmission side conversion circuit 1. |
