Design and Performance Analysis of an Envelope-Tracking Doherty Power Amplifier for 6G Wireless Base Stations

Abstract

The transition to 6G wireless communication networks requires installation of energy-efficient, high-linearity power amplifiers (PAs) as the base station RF-front-ends to address ultra-high data rates, massive connections, and onerous power limitations. The conventional PA architectures are characterized by low efficiency of the power back-off point which is experienced during power back-off especially under high peak to absolute power ratio ( PAPR ) waves which appear in broadband 6 g signals. In the efforts to solve this challenge, this paper develops a high-efficiency Doherty Power Amplifier (DPA) architecture with an Envelope Tracking (ET) that will focus on enhanced back-off efficiency and linearity of a 6G base station. The principle aim of the present work is designing, simulating and analysing an ET-enabled DPA implemented with GaN High Electron Mobility Transistor (GaN HEMT) at the 28 GHz mmWave frequency. The suggested design augments a Class-AB principle (load modulation) fundamental amplifier and a Class-C peak amplifier, whereas the ET module adjustably adjusts the drain voltage on an envelope-based correction of the RF signal to decrease power waste in terrain-off differentiations. Circuit level co-design and simulation is employed at both RF behavior, with Advanced Design System (ADS), and dynamic power supply response, with HSPICE simulation, levels. The matching network is matched in order to maximize the power transfer, and the load-pull simulations are applied to receive the best impedance conditions. Simulation results indicate that the proposed ET-DPA paves a way to a peak power-added efficiency (PAE) of 67%, small-signal gain of 13.8 dB and adjacent channel power ratio (ACPR) of -28 dBc. In addition, the amplifier achieves high efficiency (53%) at 6 dB output back-off and represents significant enhancement of conventional DPA designs. To recap it all, during envelope tracking in a Doherty architecture, an immense improvement is noticed in power efficiency and linearity in high-frequency 6G communication systems. The work provides one of the possible design strategies of energy-aware base station power amplifiers working within mmWave bands, as well as that paves the way to experimental verification and real deployment.