A 28/38 GHz Dual-Band Power Amplifier for 5G Communication
Kaijie Ding, D.M.W. Leenaerts, Hao Gao
Abstract
This work presents a 28/38 GHz dual-band power amplifier (PA) for fifth-generation (5G) communication. In this work, a T-topology-matching network is proposed at the output for its dual-band operation and low insertion loss. Also, a modified dual- <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> tank-matching method is proposed for the input and interstage part due to its wideband performance and large-impedance transformation capability. This modified dual- <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> tank boosts the transformation ratio to 30 at the interstage matching without trading bandwidth for the 28/38 GHz operation. Furthermore, circular inductors are applied to the matching networks for low insertion loss. This design is fabricated in a 0.25- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> SiGe:C BiCMOS technology with a core area of 300 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times 770\,\,\mu \text{m}^{2}$ </tex-math></inline-formula> . In combination with the proposed methods, this PA achieves 28/38 GHz dual-band operation with high power-added efficiency (PAE). At 28 GHz, the measured peak power-added efficiency (PAE <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{\mathrm {peak}}$ </tex-math></inline-formula> ) is 25%, the saturated output power ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$P_{\mathrm {sat}}$ </tex-math></inline-formula> ) is 18.8 dBm, and 1-dB compressed power ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$P_{\mathrm {1~dB}}$ </tex-math></inline-formula> ) is 17.8 dBm. At 38 GHz, those are 17.5%, 17 dBm, and 15.8 dBm, respectively.