Demodulator and frame synchronization method

摘要

A clock-frequency-deviation detecting unit detects a clock-frequency deviation based on a synchronization signal for taking a frame synchronization included in a reception signal. A clock-frequency-deviation compensating unit compensates a clock-frequency deviation of the reception signal in a former stage of an FFT unit. A timing control unit controls a frame pulse position indicating a head of a frame, based on the synchronization signal. The FFT unit performs an FFT on the reception signal with the frame pulse position as a frame head position, and a demodulating unit demodulates an output of the FFT unit.

主权项

1. A frame synchronization method in a demodulator that performs an orthogonal frequency division multiplexing demodulation, the frame synchronization method comprising:
obtaining a clock-frequency deviation based on a synchronization signal for taking a frame synchronization included in a reception signal; generating a frame pulse that indicates a head of a frame at a fixed position; compensating a clock-frequency deviation of the reception signal in a former stage of a fast Fourier transform; performing the fast Fourier transform on the reception signal that has been compensated at the compensating with the frame pulse position as a frame head position; providing the reception signal on which the fast Fourier transform has been performed directly to the obtaining of the clock-frequency-deviation; and demodulating the reception signal on which the fast Fourier transform has been performed.