TUNER FOR DEMODULATING SIGNAL CONTAINING GUARD PERIOD INTERVAL, DIGITAL DEMODULATOR, TUNER CONTROL METHOD, DIGITAL DEMODULATOR CONTROL METHOD, TUNER CONTROL PROGRAM, DIGITAL DEMODULATOR CONTROL PROGRAM, AND RECORDING MEDIUM WITH THE PROGRAM STORED

PROBLEM TO BE SOLVED: To execute optimal power control according to the state of a signal, while maintaining reliability in the data that are acquired from a signal containing guard period interval. SOLUTION: The signal containing the guard period interval includes symbols 52a, 52b, where guard period interval 54a and sub-guard period interval 53b, each having the same waveform mutually and standing adjacent in a row. In a digital demodulating device, having a tuner or demodulator for demodulating these signals, the power consumption of the tuner or the demodulator is reduced during a period that stride the boundary between the two symbols 52a, 52b that adjoin mutually. COPYRIGHT: (C)2007,JPO&INPIT