Patent ID: 6055286
Filing Date: 2000-04-25
Classification: H03L,H04L

Abstract:
A k-fold oversampling rotational frequency detector for receiving at least one phase of an input clock signal having a frequency f.sub.nom +.DELTA.f and a reference clock signal comprising:a phase sampler, receiving the input and reference clock signals, being operative to generate a first phase signal indicative of the phase of the input clock signal on at least one edge of the reference clock signal, having a phase sampling rate (k*f.sub.nom);a phase correction generator, receiving the reference clock signal, being operative to generate a phase error signal, wherein the phase error for the nth sample is .PHI..sub.error (n)=2.pi.n/k, the phase error being due to the oversampling factor k>1;a phase subtractor, receiving the first phase signal and the phase error signal, producing a phase difference signal indicative of the phase difference between the first phase signal and the phase error signal; anda rotation direction/frequency detector, receiving the phase difference signal, producing a sign output signal indicative of the sign of the .DELTA.f term of the input clock signal and a beat signal that toggles at a frequency proportional to .DELTA.f.