RFI estimation device, signal processing device and signal processing method

A signal processing device, applicable for a communication device and configured to process a received signal, comprising:

• a Radio Frequency Interference (RFI) eliminator circuit, comprising:
• a RFI estimation device, configured to generate an estimated RFI signal;
• and
• a first combiner, configured to combine the estimated RFI signal and the received signal to generate a processed signal,
• wherein the RFI estimation device comprises:
• a second combiner, configured to combine a first digital signal and a second digital signal to generate the estimated RFI signal;
• a first multiplier, configured to generate the first digital signal according to an in-phase signal and a first cosine signal;
• and
• a second multiplier, configured to generate the second digital signal according to a quadrature-phase signal and a first sine signal,
• wherein the first cosine signal and the first sine signal are generated based on a frequency and the in-phase signal and the quadrature-phase signal are generated based on the frequency and one or more harmonics of the frequency.

A signal processing method for processing a received signal, suitable for a communication device, the signal processing method comprising:

• estimating a Radio Frequency Interference (RFI) signal to generate an estimated RFI signal;
• and
• subtracting the estimated RFI signal from the received signal to generate a processed signal,
• wherein the step of estimating the RFI signal to generate the estimated RFI signal further comprises:
• generating a first sine signal and a first cosine signal according to a frequency;
• generating an in-phase signal according to the frequency and one or more harmonics of the frequency;
• generating a quadrature-phase signal according to the frequency and the one or more harmonics of the frequency;
• generating a first digital signal according to a product of the in-phase signal and the first cosine signal;
• generating a second digital signal according to a product of the quadrature-phase signal and the first sine signal;
• and
• combining the first digital signal and the second digital signal to generate the estimated RFI signal.