Method and apparatus for extended range frequency correction burst detection

A radio communication device including a local oscillator, a digital demodulator, an IF filter, and a receiver, the device including an extended frequency range FCB tone detector operable on an input signal having an FCB tone, the detector comprising:

• a first burst detection branch operable to sample the input signal, the first burst detection branch provides a first detection signal when the frequency error of the FCB is about equal to integer multiples of the quantity fs/(2*k) where fs is the bit clock rate and k is the distance between tested samples and samples of the input signal are taken near half-cycle boundaries of the input signal;
• a frequency shifter coupled with the input signal, the frequency shifter translating the input signal by a predetermined frequency offset to produce a translated input signal;
• a second burst detection branch operable to sample the translated input signal, the second burst detection branch provides a second detection signal when the frequency error of the FCB is between integer multiples of the quantity fs/(2*k) and samples of the translated input signal are taken between half-cycle boundaries of the input signal;
• and
• a combiner coupled with the first and second detection signals, the combiner indicating FCB tone detection when either of the first and second detection signals indicate FCB tone detection.