| 摘要 |
PROBLEM TO BE SOLVED: To provide the improved carrier recovery method and its device that is proper to a format for the quadrature amplitude modulation(QAM), the quadrature phase shift key(QPSK) and other wide variety of modulation systems. SOLUTION: The carrier recovery circuit 300 estimates a phase error (denoting a frequency error) between received symbols by means of any of a plurality of technologies. A phase and/or a frequency of a received carrier signal is adjusted by using the estimated frequency error and frequency lock is attained. This method and device are easily integrated with an existing carrier recovery design thereby supplementing the existing frequency and/or phase error correction technology, and frequency locking is attained in a smaller time in comparison with the case with employing only the known technology and/or in comparison with that a conventional phase detector provides an output of only a comparatively smaller DC component regardless of the presence of a comparatively large frequency offset. |
