Patent ID: 7528665

Claim:
In a multiple frequency source system having a tunable frequency source operable to tune to a predefined target frequency, and a second frequency source operable to generate a second signal at a frequency higher than the target frequency, a method for tuning the tunable frequency source to the target frequency during concurrent generation of the second signal at the higher frequency, the method comprising: controlling the tunable frequency source to tune to at least one frequency point lower than the target frequency; and thereafter, controlling the tunable frequency source to tune to the target frequency, wherein the tunable frequency source comprises a plurality of oscillators, each oscillator operable over a predefined range comprising a portion of the collective tuning range of the tunable frequency source, and wherein controlling the tunable frequency source to tune to at least one frequency point lower than the target frequency comprises selecting, from the plurality of oscillators, a tuning oscillator operable to tune (i) below the target frequency and (ii) to the target frequency.