| 摘要 |
PURPOSE: To provide a quadrature frequency division multiplexing system(OFDM) which is adaptive to QAM. CONSTITUTION: For modulation, a modulation device for OFDM which performs discrete inverse Fourier transformation as for plural points is provided with a reference code sending-out device 54 which inserts a reference signal, e.g. data in a pseudo-random series periodically into between normal data to be sent, and the reference signal is inserted into the normal signal to be sent and they are modulated and sent out. For demodulation, a demodulation device for OFDM which performs discrete Fourier transformation as to plural points is provided with a reference signal detection device which detects the reference signal, a device which calculates a phase error and an amplitude error by using the detected reference signal, and a device which corrects a received transmitted signal by referring to the phase error and amplitude error. |
