Implementation and Measurement of Low-Noise Amplifier Using RF Short-Circuit Capacitor

This paper presents the design of a highly integrated low-noise amplifier (LNA) for the 5G new radio (NR) band. The proposed LNA integrates two LNAs into a single chip die for the n77 (3.3~4.2 GHz) and n79 (4.4~5.0 GHz) bands and includes a bypass mode for flexible receiver operation according to the input signal strength. It also includes an input/output matching network circuit, electrostatic discharge (ESD) protection circuits, and part of the decoupling network circuit for RF short references for high integration and fidelity. The proposed LNA achieves gains of 21.3 dB and 18.2 dB, with noise figures of 1.68 dB and 1.43 dB, in the n77 and n79 bands, respectively. In bypass mode, the system operates with gains of −4.41 dB and −6.72 dB, with noise figures of 5.09 dB and 7.42 dB, respectively. The integrated LNA has a chip size of 1.5×1.1 mm2 and consumes 12 mW of power.