In this paper, an innovative approach to achieve broadband linear power amplifier (PA) with a continuous broadband is presented. The proposed method mainly depends on the theory of control of intermodulation products and harmonics. This method results in a continuous sweet spots over a wide bandwidth. Based on the continuous sweet spots, a suboptimal solution is derived for improving the efficiency and linearity of broadband PAs. To verify the effectiveness of this method, one broadband PA operating over 4.5–5.5[Formula: see text]GHz is developed and measured, it indicates that the peak output power of the PA is 35–57[Formula: see text]dBm for a small signal input with a gain of 12[Formula: see text]dB, and the peak drain efficiency (DE) of the PA is larger than 57% over the whole working band. However, when the PA is stimulated by a 5[Formula: see text]MHz two-tone signal input, we observe that the DE keeps above 38% under the condition of the measured third-order intermodulation distortion (IMD3) is not larger than [Formula: see text][Formula: see text]dBc.
A Discrete-Amplitude Pulse Width Modulation for a High-Efficiency Linear Power Amplifier
