Patent ID: 8000428

Claim:
A method of estimating a gain characteristic of a digitally controlled oscillator in a frequency synthesizer, comprising: providing a digital control word that includes information for use in tuning the digitally controlled oscillator; obtaining a first plurality of values of the digital control word produced by the frequency synthesizer while the digitally controlled oscillator is operating at a first frequency; changing the operating frequency of the digitally controlled oscillator from said first frequency by a predetermined frequency change amount; after said changing step, obtaining a second value of the digital control word produced by the frequency synthesizer; and using the first plurality of values, the second value and the frequency change amount to estimate the gain characteristic of the digitally controlled oscillator, including producing from the first plurality of values a representative value which represents the first plurality of values, and using the representative value, the second value and the frequency change amount to estimate the gain characteristic of the digitally controlled oscillator.