| 摘要 |
PROBLEM TO BE SOLVED: To prevent the error in data judgment in the decoding of the radio communication signal of an orthogonal frequency division/multiplex system(OFDM) which uses the modulation system of multivalued QAM. SOLUTION: The timing of the respective time area signals of base bands Ich and Qch is decided in a synchronizing part 1 and the signals are transformed into frequency area signals in a Fourier transformation processing part 2. The fluctuation of the amplitude and the phase of data signals in Ich and Qch are estimated in an Ich estimating part 3 and a Qch-estimating part 4, based on a pilot signal in the transformed signals. Thresholds are corrected in an Ich threshold correcting part 5 and a Qch threshold correcting part 6, based on the estimation result. The data signals of Ich and Qch, which pass through a delay part 7 or 8 from the Fourier transformation processing part 2, are data-corrected based on the corrected thresholds, and the pilot signals. The data signal from a data correcting part 9 is judged for the data in a judging part 10 by using the corrected thresholds. |
