Design of a broadband Doherty power amplifier with a modified load modulation network. Issue 12 (26th September 2022)

• Record Type: Journal Article
• Authors: Lai, Zejie; Liu, Guohua; Cheng, Zhiqun; Lin, Yijun; Zhong, Huabang
• Is Part Of: International journal of RF and microwave computer-aided engineering. Volume 32:Issue 12(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-09-26
• Subjects: back‐off efficiency -- broadband -- Doherty power amplifier (DPA) -- load modulation network; Microwave devices -- Computer-aided design -- Periodicals; Computer-aided engineering -- Periodicals; 621.3813
• DOI: 10.1002/mmce.23432
• Languages: English
• ISSNs: 1096-4290

Abstract

Abstract: This article proposes a modified load modulation network (LMN) to adjust the structure of the traditional Doherty power amplifier (DPA) by changing one λ/4 microstrip line at the output of the main power amplifier into two in the traditional DPA and connecting a terminal open‐circuit λ/2 line at the junction point which can reduce the frequency dispersion effect to achieve expanding bandwidth while maintaining saturation efficiency and back‐off efficiency. A 2.6–3.6 GHz DPA is designed and fabricated for verification. The measured results show that the saturated output power is 42.5–44 dBm and the saturated efficiency is between 63% and 69% in target band with a gain from 8.5 to 9.5 dB. At 6 dB output power back‐off, the drain efficiency is 44%–50%. And the adjacent channel power ratio (ACPR) is better than −32 dBc.