Methods and mobile communication devices for performing spur relocation for phase-locked loops

A mobile communication device adapted to perform spur relocation for a digital phase-locked loop, comprising:

• a receiver to determine a first frequency channel of interest and to identify a first frequency command word corresponding to the first frequency channel of interest;
• control logic circuitry to identify a first frequency at which a first fractional spur associated with the first frequency command word starts to occur and to determine whether the identified first frequency is within the first frequency channel of interest;
• and
• a programmable feedback divider to change the first frequency command word to a second frequency command word, wherein a second fractional spur associated with the second frequency command word occurs at a second frequency outside the first frequency channel of interest.

An apparatus comprising:

• a digital phase-locked loop to receive a frequency command word corresponding to a first frequency channel of interest and generate an output frequency based on the frequency command word, the digital phase-locked loop comprising:
• means for determining that a first frequency at which a first fractional spur associated with a first frequency command word occurs is within the first frequency channel of interest;
• and
• means for modifying the first frequency command word to move the first fractional spur to a second frequency outside the first frequency channel of interest without affecting the output frequency.