| 摘要 |
PROBLEM TO BE SOLVED: To more exactly detect a carrier frequency error. SOLUTION: An amplitude conversion circuit 311 calculates the amplitude of an OFDM frequency domain signal and supplies it to a threshold comparator circuit 312. The threshold comparator circuit 312 preliminarily stores an upper limit threshold TH (max)of a reliable amplitude value and a lower limit threshold TH (min) of the reliable amplitude value when the amplitude value supplied from the amplitude conversion circuit 311 is larger than the upper limit threshold TH (max) or smaller than the lower limit threshold TH (min), generates a low reliability flag and supplies it to accumulation circuits 333-1 to 333-2n. The accumulation circuits 333-1 to 333-2n do not accumulate likelihood supplied from likelihood conversion circuits 332-1 to 332-2n and discard it when the low reliability flag is supplied from the threshold comparator circuit 312. Thus, a signal with low reliability is excluded. This invention is applicable to an OFDM receiver. COPYRIGHT: (C)2005,JPO&NCIPI
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