| 摘要 |
PURPOSE: An apparatus and method for equalizing a channel in an OFDM(Orthogonal Frequency Division Multiplexing) system using a differential modulating scheme are provided to estimate a channel differential element using a cyclic prefix property of a guard interval and a valid symbol interval. CONSTITUTION: A synchronization part(211) synchronizes a received signal with time and frequency. A signal processing part performs FFT(Fast Fourier Transform) of an OFDM symbol which is synchronized by time and frequency. A channel variation estimating part(310) extracts a duplication target symbol from a guard interval symbol and a valid symbol interval by receiving the OFDM symbol which is synchronized by time and frequency from the synchronization part. The channel variation estimating part calculates channel differential components for one OFDM symbol using each symbol in which FFT is performed. A channel variation correction part(320) corrects a differentially demodulated signal which is outputted from the signal processing part. [Reference numerals] (211) Synchronization part; (212) FFT part; (213) FFT storage part; (214) Differential modulation part; (215) QPSK modulation part; (310) Channel variation estimating part; (311) Guard interval extraction part; (312) FFT part; (313) Channel differential component calculation part; (314) Channel differential component accumulation part; (320) Channel variation correction part |
