| 摘要 |
PURPOSE:To obtain a correct demodulated signal by estimating and predicting the temporal fluctuation of a detected phase error generated by an initial phase error and a frequency error (offset) at high speed when demodulation is performed sequentially by a quasi-synchronous detecting system. CONSTITUTION:A Wiener filter is comprised of a phase control circuit 28 which performs complex weighing on a received complex input signal U, and minimizes the square mean value of difference with a desired signal, and a stationary phase error due to the frequency offset can be completely eliminated by performing frequency error estimation at a frequency compensation circuit 44 based on fluctuation of one symbol of mutual correlation value between the complex input signal U and a demodulated signal D in the Wiener filter, and estimating the initial phase error at a phase error estimation circuit 21 based on the above information, and performing phase equalization considering phase fluctuation due to the frequency error at a phase equalization circuit 22, thereby, the correct demodulated signal D can be obtained. |
