Patent ID: 8719614

Claim:
An apparatus for generating a timing signal, comprising: an input for receiving a first signal indicating successive time intervals; means for receiving a second signal indicating successive time intervals; a generator adapted to generate a timing signal based on the second signal and on a relationship between one or more time intervals of said first signal and one or more time intervals of said second signal; and determining means for determining said relationship from said first and second signals; wherein said relationship is one or both of (1) a number of successive time intervals of the second signal in one or more time intervals of the first signal and (2) a number of successive time intervals of the first signal in one or more successive time intervals of the second signal; and, wherein said determining means is adapted to determine an average number of time intervals of said second signal in a time interval of said first signal, and to determine a first average from a first plurality of samples, each sample comprising the number of time intervals of said second signal in a time interval of said first signal, to determine a first difference between said first average and one of said samples, to determine a second average from a second plurality of samples, at least one sample of said second plurality of samples not included in said first plurality of samples, to determine a second difference between said second average and a sample of said second plurality of samples, and to determine a deviation based on said first and second differences.