TRANSMISSION/RECEPTION SYSTEM OF ORTHOGONAL FREQUENCY DIVISION MULTIPLEX SIGNAL AND TRANSMISSION/RECEPTION METHOD OF ORTHOGONAL FREQUENCY DIVISION MULTIPLEX SIGNAL

摘要

PPROBLEM TO BE SOLVED: To enable a receiver side to easily obtain an accurate synchronous signal, in an OFDM signal transmission and reception system. PSOLUTION: A transmission side device of this system has an IFFT (inverse fast Fourier transform) circuit for generating a multivalued QAM modulation signal, a guard interval setting circuit, and a clock signal generating circuit for driving both the circuits. Pilot signals having phases kept to be constant value and higher order frequencies in a plurality of symbol sections are generated by the IFFT circuit. The pilot signals are set so as to exist at an integer waveform, to exist at odd number times half-wavelengths exist, to exist as signals in a real part, or to be increased fourfold and exist as a single frequency, in the guard interval. The pilot signals are sent out continuously across the plurality of symbol sections, and a receiver side generates an accurate clock signal on the basis of the pilot signals. PCOPYRIGHT: (C)2004,JPO