Design and Analysis of a 22.6-to-73.9 GHz Low-Noise Amplifier for 5G NR FR2 and NR-U Multiband/Multistandard Communications

This article presents the analysis and design of a 22.6-to-73.9 GHz ultra-wideband low-noise amplifier (LNA) with flat in-band power gain for millimeter-wave applications, supporting all allocated fifth-generation new radio (5G NR) frequency range 2 (FR2) bands at 24/28/39/47 GHz, as well as the potential 5G NR-U bands within the unlicensed 57–71 GHz spectrum. The proposed LNA consists of two amplifier stages and achieves ultra-wideband performance by utilizing various bandwidth extension techniques. It introduces a synergistic equalization technique that integrates shunt feedback and dual inductive peaking for design harmony of optimized bandwidth, noise reduction, and stability compared to reported methods. Additionally, a resonant feedback compensation equalization (RFCE) technique is presented to mitigate high-frequency gain roll-off, enhance gain flatness, and further expand the operation bandwidth. The principles of gain, bandwidth, and noise improvement are analyzed theoretically. To validate the proposed techniques, an LNA is designed and fabricated utilizing the IHP SG13G2 0.13-<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu $ </tex-math></inline-formula> m silicon-germanium (SiGe) technology, featuring peak <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$f_{T}/f_{\text {MAX}}$ </tex-math></inline-formula> of 350/450 GHz. The measurement results indicate significantly enhanced gain flatness, extended bandwidth, and improved noise figure (NF). Specifically, the proposed amplifier shows a 15.2 dB peak gain, −7.4 to −2.8 dBm output in 1-dB compression point power (OP1dB), and 4.06–4.94 dB NF in a 3-dB bandwidth from 22.6 to 73.9 GHz. The circuit occupies a compact core area of 0.06 mm2 and consumes 17.5 mW power consumption from a 1.2 V supply.