Signal processing apparatus and associated method

摘要

A signal processing apparatus includes an initial detecting module, a mixer, a symbol rate detecting module, a judging module and a correcting module. The initial detecting module determines an initial carrier frequency offset of an input signal according to a spectrum of the input signal. The mixer adjusts the input signal according to the initial carrier frequency offset to generate a frequency-compensated signal. The symbol rate detecting module determines a symbol rate of the input signal. The judging module judges whether the initial carrier frequency offset is correct according to the frequency-compensated signal. When a judgment result of the judging module is negative, the correcting module determines a corrected carrier frequency offset according to the symbol rate and the spectrum.

主权项

1. A signal processing apparatus, comprising:
an initial detecting module, for determining an initial carrier frequency offset of an input signal according to a spectrum of the input signal; a mixer, for adjusting the input signal according to the initial carrier frequency offset to generate a frequency-compensated signal; a symbol rate detecting module, for determining a symbol rate of the input signal; a judging module, for performing a phase recovery on the frequency-compensated signal, and judges whether the initial carrier frequency offset is correct as a judgement result according to whether the phase recovery renders a phase locking; and a correcting module, coupled to the mixer, for selectively determining a corrected carrier frequency offset according to the symbol rate and the spectrum and providing the corrected carrier frequency offset to the mixer based on the judgment result, wherein when the judgment result of the judging module is negative, the correcting module selects a frequency segment having a width corresponding to the symbol rate from the spectrum, and renders the corrected carrier frequency offset with a difference between a center frequency of the frequency segment and a reference frequency.