Patent ID: 8149937

Claim:
A signal receiver, comprising: a carrier removal module, generating a carrier signal with a frequency of an estimated carrier frequency, generating at least one delta carrier signal with a frequency of the estimated carrier frequency plus a delta frequency, removing the carrier signal from a first signal to obtain a second signal, and removing the delta carrier signal from the first signal to obtain a third signal; a Fast Fourier Transformation (FFT) module, coupled to the carrier removal module, deriving a series of first FFT values from the second signal, and deriving a series of second FFT values from the third signal; and a signal processor, coupled to the carrier removal module and the FFT module, estimating the carrier frequency of the first signal to obtain the estimated carrier frequency, determining the delta frequency for the carrier removal module, estimating a residual Doppler frequency of the second signal according to both the first FFT values and the second FFT values, and adjusting the estimated carrier frequency according to the residual Doppler frequency.