A method of detecting frequency errors exceeding a predetermined limit in a
sampled signal includes the step of determining a peak amplitude of the
signal at a tone frequency for a first frame of samples of the sampled
signals using a filter having a first amplitude versus frequency response.
A peak amplitude of signal at the tone frequency is determined for a
second frame of samples of the sampled signal using a filter having a
second amplitude versus frequency response. A ratio between the peak
amplitude of the first frame and the peak amplitude of the second frame is
calculated and compared against a threshold to detect frequency errors
exceeding the predetermined limit. Among other things, this method
decouples the frequency error detection problem from the twist factor
estimation problem.
