摘要 |
PROBLEM TO BE SOLVED: To realize a transmission device, by which an accurate synchronous signal can be easily obtained on the receiving side, in transmitting an OFDM signal. SOLUTION: A transmission side device of this system has an IFFT circuit which generates a multivalued QAM modulation signal, a guard interval setting circuit, and a clock signal generating circuit which drives both the circuits. Pilot signals, whose phases are set at prescribed values at starting points of a plurality of symbol sections and which have higher order frequencies with prescribed ratios to a frequency of a clock signal, are generated by the IFFT circuit. The pilot signals are sent out continuously across the plurality of symbol sections, including guard interval sections and the pilot signals, are demodulated on a receiving device side to generate a clock signal for driving an FFT. |