Novel Wideband Fully Integrated GaN Power Amplifier Design Using a Hybrid Bandpass-Lowpass Output Matching Network
Jie Shi, Wenqi Dai, Xiaohu Fang, Xin Yu Zhou, Jiangwei Sui, Jing Xia, Kwok‐Keung M. Cheng
Abstract
This letter proposes a novel fully integrated harmonic-tuned wideband and high-efficiency GaN power amplifier (PA) for <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$C$ </tex-math></inline-formula> -band application. The proposed PA employs a hybrid bandpass-lowpass output matching network (OMN) that offers fundamental impedance matching, drain biasing as well as harmonic control with only two inductors. The proposed PA is designed and fabricated using a commercial <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.25~\mu \text{m}$ </tex-math></inline-formula> GaN-on-SiC HEMT process. Measurement results show that, over a frequency band of 3.8–6.4 GHz, this PA can provide a saturation output power of 38.3–40.2 dBm and excellent peak power-added efficiency (PAE) of 50%–63% with a chip size of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.5\times2.25$ </tex-math></inline-formula> mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . When excited by a 100 MHz 64-quadrature amplitude modulation (QAM) signal, without using any digital pre-distortion (DPD), the proposed PA can deliver an average PAE >33% with an adjacent channel power ratio (ACPR) <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$ < -35$ </tex-math></inline-formula> dBc and an error vector magnitude (EVM) of 2.4%–5.1% over 3.8–6.4 GHz.