摘要 |
An automatic frequency control method re-modulates a binary data sequence output from an equalizer using the convolution of an estimated channel characteristic value function and a transfer function of the modulator in the transmitter of a communication system, to obtain a reference phase. The reference phase then is compared with a receiving phase to produce a phase error value. The phase error value is converted into a frequency error value, which is then converted into an analog control voltage and applied to a voltage controlled oscillator. Apparatus for performing the method includes an equalizer, a channel characteristic estimator, a re-modulator, a phase comparator, a frequency error estimator and a digital-to-analog converter, to thus improve the receiving performance of a receiver by digital implementation.
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