A 4.8-6.4-GHz GaN MMIC Front-End Module with Enhanced Back-off Efficiency and Compact Size

• Main Authors: Lv, Guansheng, Chen, Wenhua, Chen, Xiaofan, Chen, Long, Feng, Zhenghe
• Format: Conference Proceeding
• Language: English
• Subjects: class-G; compact; Finite element analysis; Front-end module (FEM); gallium nitride (GaN); high efficiency; low-noise amplifier (LNA); monolithic microwave integrated circuit (MMIC); power amplifier (PA); Power measurement; Predistortion; Radiofrequency integrated circuits; Semiconductor device measurement; Switches; Topology; transmit/receive (T/R) switch
• ISSN: 2375-0995
• DOI: 10.1109/RFIC54547.2023.10186156

A back-off efficient transmit/receive (T/R) front-end module (FEM) architecture is presented in this paper. On one hand, switchless class-G (SLCG) topology is adopted for power amplifier (PA) to improve the back-off efficiency in TX mode. On the other hand, co-design asymmetric T/R switch scheme is applied to reduce the switch loss in TX path. A 4.8-6.4-GHz FEM is implemented in a 0.15-µm GaN-HEMT process for validation, and the chip size is only 1.45 mm ×1.6 mm. The TX mode realizes a saturated power of 37.2-38.9 dBm and a 6-dB back-off drain efficiency (DE) of 40.2%-43.4%. Applying a 160-MHz LTE signal with 8.5-dB PAPR, an average DE of 33.3%-37% at an average power of 28.3-30 dBm is measured, and the ACPR is better than -46 dBc after digital predistortion. The RX mode achieves a noise figure of 1.8-2.2 dB and an IIP3 of 20.8-25 dBm.