Multi-phase clock generator circuit

A radio frequency transmitter comprising:

• a multi-phase clock generator circuit, the multi-phase clock generator circuit including a voltage controlled phase shifter adapted to generate an interpolated clock signal having an interpolated phase shift with respect to at least two received reference clock signals, and the multi-phase clock generator circuit further including a feedback circuit adapted to generate, in response to a detected phase difference between the interpolated clock signal and the reference clock signals, a control voltage applied to the voltage controlled phase shifter for tuning the voltage controlled phase shifter;
• an I/Q data modulator that receives I/Q input signals, the at least two reference clock signals, and the interpolated clock signal, and configured to output a modulated signal;
• and
• a power amplifier configured to receive the modulated signal output by the I/Q data modulator.

A method for generating clock signals with adjustable phase shift, the method comprising the steps of:

• receiving reference clock signals from reference clock sources;
• generating by a voltage controlled phase shifter an interpolated clock signal having an interpolated phase shift with respect to the received reference clock signals;
• detecting a phase difference between the generated interpolated clock signal and the received reference clock signals;
• generating a control voltage in response to the detected phase difference applied to the voltage controlled phase shifter for tuning the voltage controlled phase shifter;
• and
• outputting the generated interpolated clock signal with the interpolated phase shift.