Abstract: A power combiner comprises a first transmission line or lumped circuit element, a second transmission line or lumped circuit element, a third transmission line or lumped circuit element, a fourth transmission line or lumped circuit element and a balance capacitive element (Cbal) or balance inductive element (Lbal). The first transmission line or lumped circuit element is coupled to a first port. The second transmission line or lumped circuit element is coupled between the first transmission line or lumped circuit element and a common port. The third transmission line or lumped circuit element is coupled to a second port. The fourth transmission line or lumped circuit element is coupled between the third transmission line or lumped circuit element and the common port.

Abstract: A radio frequency (RF) amplification method, comprising: modulating a first digital carrier signal with a digital envelop signal to generate digital RF pulse signals having a first frequency, converting the digital RF pulse signals into analog RF pulse signals, amplifying the analog RF pulse signals to generate an RF output signal, converting an analog feedback signal sampled from the RF output signal into digital feedback signals; demodulating the digital feedback signals with a second digital carrier signal to generate an in-phase (I) signal and a quadrature (Q) signal, and generating an amplitude setting signal for adjusting an amplitude of the digital envelop signal and a phase setting signal for adjusting a phase of the first digital carrier signal according to the I signal and the Q signal.