| 摘要 |
PROBLEM TO BE SOLVED: To provide a receiver that correctly detects even an error of a signal frequency comparatively large and corrects it automatically in the case of the receiver for a digital audio broadcast program employing the orthogonal frequency division multiplex OFDM system where each carrier is subjected to differential phase modulation. SOLUTION: A synchronizing signal detector 8 operated through the detection of an envelope of a broadcast wave reception signal is used to conduct synchronization with a transmission frame and a phase error detector 12 detects a frequency error to conduct frequency tuning. Furthermore, a 1st frequency error detector 19 detects a frequency error in the unit of almost carrier interval and a 2nd frequency error detector 20 detects a frequency error of mis-locking resulting from detection of a phase error, then the frequency control range is extended. Moreover, the operations above are properly controlled by a controller 21 to ensure each operation of synchronization and frequency tuning.
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