A highly linearized second harmonic injected GaN power amplifier. Issue 10 (11th June 2022)

• Record Type: Journal Article
• Authors: Abbasnezhad, F.; Tayarani, M.; Abrishamifar, A.; Nayyeri, V.
• Is Part Of: Microwave and optical technology letters. Volume 64:Issue 10(2022)
• Page Start: 1732
• Page End: 1739
• Publication Date: 2022-06-11
• Subjects: GaN -- linearization -- power amplifier -- second harmonic injection -- soft saturation; Microwaves -- Periodicals; Optics -- Periodicals; 621
• DOI: 10.1002/mop.33360
• Languages: English
• ISSNs: 0895-2477

Abstract

Abstract: This article presents an active second harmonic injection technique for linearizing power amplifiers (PAs). In this method, a second harmonic signal with adjustable amplitude and phase, which is generated by a differential pair network, is injected into the input of a PA in a forward path. The tunable input and output matching circuits of the proposed second harmonic generator provide linearization capability in a wide frequency band. To validate the concept, the proposed second harmonic injection technique was implemented to linearize a GaN PA working around 1.5 GHz. It was shown that applying the proposed linearization method increases the output 1‐dB compression point from 33.5 dBm to 39.5 dBm (about 2 dB lower than saturation power) under the CW signal. Furthermore, the backed‐off efficiency at a higher adjacent channel power ratio was improved, and improvement of 16 dB at 200 MHz frequency bandwidth was achieved for an 8 MS/s 64‐quadratic‐amplitude modulation signal.