# A 6–18 GHz High-Efficiency GaN Power Amplifier Using Transistor Stacking and Reactive Matching

## TL;DR

This paper presents a high-efficiency GaN power amplifier operating from 6 to 18 GHz, using transistor stacking and reactive matching to achieve good performance across a wide frequency range.

## Contribution

The novel use of transistor stacking and a two-stage reactive matching network enables high gain, power, and efficiency in a wideband GaN power amplifier.

## Key findings

- The amplifier achieves 25–29 dB small signal gain across 6–18 GHz.
- It delivers 40.8–42.5 dBm output power with 27–38% power-added efficiency.
- The design is implemented in a compact 4.5 × 3.4 mm² MMIC using GaN-on-Si HEMT technology.

## Abstract

This article presents the design and implementation of a 6–18 GHz GaN monolithic microwave integrated circuit (MMIC) power amplifier (PA). A two-stage cascaded reactive matching network structure based on transistor stacking technology is employed to achieve circuit gain, and a multi-cell combination is used in the final stage to simultaneously achieve high power and high efficiency. For demonstration, a prototype of the proposed PA with an area of 4.5 × 3.4 mm2 is fabricated in a 0.1 µm GaN-on-Si high-electron-mobility transistor (HEMT) process. The measured results of the GaN PA show a small signal gain of 25–29 dB, an output power of 40.8–42.5 dBm, and a power-added efficiency (PAE) of 27–38% in the operating frequency range of 6–18 GHz.