Patent ID: 8644783

Claim:
A method of determining an offset term for a synthesizer signal during a second state-of-lock interval following a loss-of-lock interval with respect to the phase of the synthesizer signal during a first state-of-lock interval preceding the loss-of-lock interval, the method comprising: during the state-of-lock intervals, locking the synthesizer signal to a reference signal via a feedback path in that a phase relation between the reference signal and a frequency-divided signal is held constant, where the frequency-divided signal is derived from the synthesizer signal such that the frequency of the frequency-divided signal equals the frequency of the synthesizer signal divided by a fractional divide ratio, by assessing a cycle difference between the number of cycles of the reference signal and the number of cycles of the frequency-divided signal of the feedback path during the loss-of-lock interval, and determining the offset term of the synthesizer signal for the feedback path as a numerical value proportional to the product of the divide ratio and the cycle difference.