High-linearity power amplifier based on GaAs HBT

TL;DR

This paper introduces a high-linearity GaAs HBT power amplifier optimized for Wi-Fi 6E, employing advanced techniques like inter-modulation cancellation and adaptive biasing to enhance broadband linearity and power performance.

Contribution

It presents a novel design integrating third-order inter-modulation cancellation, harmonic suppression, and adaptive biasing for improved linearity in GaAs HBT power amplifiers.

Findings

Achieves S21 > 31dB across 5.125-7.125 GHz

Maximum linear output power of 26.5dBm

Layout area of 2.34mm2

Abstract

This paper presents a power amplifier designed for Wi-Fi 6E using the 2 um gallium arsenide (GaAs) heterojunction bipolar transistor (HBT) process. By employing third-order inter-modulation signal cancellation, harmonic suppression, and an adaptive biasing scheme, the linearity performance of the circuit is improved. To achieve broadband performance, the power amplifier also incorporates gain distribution and multi-stage LC matching techniques. The measurement results indicate that, under a 5V supply voltage, it can achieve S21 greater than 31dB, delta G of 0.723dB, and P1dB of 30.6dB within the 5.125GHz-7.125GHz frequency band. The maximum linear output power, which satisfies AM-AM < 0.2dB and AM-PM < 1{\deg}, is 26.5dBm, and the layout area is 2.34mm2.