| 摘要 |
PROBLEM TO BE SOLVED: To easily obtain an accurate synchronization signal at a receiver side when an OFDM signal is transmitted and received. SOLUTION: The transmitter side of an OFDM signal has an IFFT circuit generating a multi-value QAM modulation signal, and a guard interval setting circuit. The IFFT circuit sets a phase to a predetermined value at start points of a plurality of symbols, a pilot signal having a higher-order frequency is generated which exists as a discontinuous waveform signal at a head of a guard interval, formed into a signal having a single frequency by 4 multiplication, and held in a reverse phase to each other in adjacent effective symbol sections, and the pilot signal is continuously sent out over the plurality of symbol sections including the guard interval section. A receiver side demodulates the pilot signal to obtain the phase information of the pilot signal, and converts the multi-value QAM modulation signal into the digital information signal using the phase information. COPYRIGHT: (C)2006,JPO&NCIPI |
