| 摘要 |
An RF power amplifier has an RF input port (11) to which an RF input signal is coupled, an RF output port from which an amplified RF output signal is derived. An RF carrier cancellation combiner (23) has a first input (22) coupled to the RF input port (11) and a second input (21) coupled to the RF output port. The carrier cancellation combiner (23) produces an RF error signal (24) representative of RF distortion of a signal flow path through the RF amplifier between the RF input port (11) and the RF output port. To reduce a residual carrier signal in the RF error signal (24), a wideband autocalibrating correlator correlates a reference signal (31), representative of the RF input signal, with the RF error signal (24), producing a control signal, which is coupled to a vector modulator (12) to modify the signal flow path through the RF amplifier. A digital signal processor (100) within the correlator measures DC distortion associated with the multiplier components of the correlator and controllably removes DC distortion from the control signal, so that modification of the signal flow path through the RF amplifier by the vector modulator (12) is controlled with a higher precision, providing maximal carrier cancellation. |
