Dual-mode orthogonal Doherty power amplifier with efficiency enhancement and load mismatch adaptability

Abstract

This study proposes an efficiency-enhanced dual-mode orthogonal Doherty power amplifier (ODPA) architecture. The operation theory, design process, and implementation of the proposed ODPA are introduced in detail. By introducing an orthogonal architecture with control signal power injection and incorporating a modified output matching network, the efficiency of Doherty power amplifiers under active load modulation can be enhanced. Furthermore, owing to the additional degrees of freedom provided by the orthogonal architecture, which enables independent amplitude and phase control and dynamic reshaping of the load modulation trajectories, and the dual-mode reciprocal bias configuration, the proposed ODPA exhibits high adaptability to load mismatch. To validate the proposed architecture, a 2.1-GHz dual-mode ODPA is designed and fabricated. With a matched load, the fabricated dual-mode ODPA exhibites over 60% drain efficiency throughout the power range from 6-dB output back-off (OBO) to saturation. For mismatched loads with a 2:1 voltage standing wave ratio, a saturated output power of 42.8-44.6 dBm and OBO efficiency of 47.2%-58.1% are obtained through mode reconfiguration.

Keywords

Doherty power amplifier / Dual mode / High efficiency / Load mismatch / Orthogonal / Reciprocal bias

References

[1] Barthwal A , Rawat K , Koul SK , 2021. Dual input digitally controlled broadband three-stage Doherty power amplifier with back-off reconfigurability. IEEE Trans Circ Syst I Regul Pap, 68 (4): 1421- 1431.

[2] Chappidi CR , Sharma T , Sengupta K , 2020. Multi-port active load pulling for mm-Wave 5G power amplifiers:bandwidth, back-off efficiency, and VSWR tolerance. IEEE Trans Microw Theory Tech, 68 (7): 2998- 3016.

[3] Chen XF , Zhao M , Chen WH , et al., 2022. A 700-2800MHz switchless Class-G power amplifier with two-quadrant modulation for back-off efficiency improvement. Proc IEEE/MTT-S Int Microwave Symp, p.410- 413.

[4] Colantonio P , Giannini F , Giofre R , et al., 2009. Theory and experimental results of a Class F AB-C Doherty power amplifier. IEEE Trans Microw Theory Tech, 57 (8): 1936- 1947.

[5] Collins DJ , Quaglia R , Powell JR , et al., 2020. The orthogonal LMBA:a novel RFPA architecture with broadband reconfigurability. IEEE Microw Wirel Compon Lett, 30 (9): 888- 891.

[6] Dai ZJ , Kong SM , Feng W , et al., 2024. Design of wideband asymmetric Doherty power amplifier using a new phase compensation technique. IEEE Trans Circ Syst I Regul Pap, 71 (3): 1093- 1104.

[7] Donahue DT , de Falco PE , Barton TW , 2020. Power amplifier with load impedance sensing incorporated into the output matching network. IEEE Trans Circ Syst I Regul Pap, 67 (12): 5113- 5124.

[8] Fang XH , Liu HY , Cheng KKM , et al., 2018. Two-way Doherty power amplifier efficiency enhancement by incorporating transistors' nonlinear phase distortion. IEEE Microw Wirel Compon Lett, 28 (2): 168- 170.

[9] Gao RB , Shi WM , Dai ZJ , et al., 2024. Dual-mode orthogonal Doherty power amplifier with efficiency enhancement and load mismatch adaptability. Proc IEEE MTT-S Int Wireless Symp, p.1- 3.

[10] Gonçalves CF , Barradas FM , Nunes LC , et al., 2022. Quasi-load insensitive Doherty PA using supply voltage and input excitation adaptation. IEEE Trans Microw Theory Tech, 70 (1): 779- 789.

[11] Guo JC , Gong PZ , Chen KL , 2025. Theory and design of pseudo-Doherty load-modulated double balanced amplifier with intrinsic insensitivity to antenna VSWR. IEEE Trans Circ Syst I Regul Pap, 72 (5): 2048- 2060.

[12] Han YJ , Gao RB , Liu S , et al., 2024. Enhanced dual-mode reciprocal Doherty power amplifier using modified combining load and parameter sweeping analysis. IEEE Trans Circ Syst I Regul Pap, 71 (7): 3086- 3097.

[13] Hu S , Kousai S , Wang H , 2015. Antenna impedance variation compensation by exploiting a digital Doherty power amplifier architecture. IEEE Trans Microw Theory Tech, 63 (2): 580- 597.

[14] Kalyan R , Rawat K , Koul SK , 2019. A digitally assisted dual-input dual-band Doherty power amplifier with enhanced efficiency and linearity. IEEE Trans Circ Syst II Express Briefs, 66 (2): 297- 301.

[15] Kang H , Lee H , Oh H , et al., 2017. Symmetric three-way Doherty power amplifier for high efficiency and linearity. IEEE Trans Circ Syst II Express Briefs, 64 (8): 862- 866.

[16] Lyu H , Chen KL , 2022. Analysis and design of reconfigurable multi-band mismatch-resilient quasi-balanced Doherty power amplifier for massive MIMO systems. IEEE Trans Microw Theory Tech, 70 (10): 4410- 4421.

[17] Lyu H , Cao YC , Chen KL , 2021. Linearity-enhanced quasi-balanced Doherty power amplifier with mismatch resilience through series/parallel reconfiguration for massive MIMO. IEEE Trans Microw Theory Tech, 69 (4): 2319- 2335.

[18] Moon J , Kim J , Kim J , et al., 2011. Efficiency enhancement of Doherty amplifier through mitigation of the knee voltage effect. IEEE Trans Microw Theory Tech, 59 (1): 143- 152.

[19] Pang JZ , He SB , Huang CY , et al., 2015. A post-matching Doherty power amplifier employing low-order impedance inverters for broadband applications. IEEE Trans Microw Theory Tech, 63 (12): 4061- 4071.

[20] Pang JZ , Han YJ , Peng J , et al., 2024. Dual-mode three-way Doherty power amplifier with extended high-efficiency range against load mismatch. IEEE Trans Microw Theory Tech, 71 (5): 2016- 2028.

[21] Quaglia R , Powell JR , Chaudhry KA , et al., 2022. Mitigation of load mismatch effects using an orthogonal load modulated balanced amplifier. IEEE Trans Microw Theory Tech, 72 (7): 4058- 4067.

[22] Saad P , Hou R , Hellberg R , et al., 2019. The continuum of load modulation ratio from Doherty to traveling-wave amplifiers. IEEE Trans Microw Theory Tech, 67 (12): 5101- 5113.

[23] Shi WM , Li XL , Gao Y , et al., 2023. Load mismatch compensation of Doherty power amplifier using dual-input and mode reconfiguration techniques. IEEE Trans Circ Syst I Regul Pap, 70 (7): 2774- 2787.

[24] Sun JX , Lin F , Zhou XY , et al., 2021. Design of 74% fractional bandwidth continuous-mode Doherty power amplifier using compensation susceptance. IEEE Trans Circ Syst II Express Briefs, 68 (6): 1827- 1831.

[25] Tang YX , Feng WJ , Zhou XY , et al., 2023. Broadband high-efficiency dual-mode Doherty power amplifier using hybrid F/F^-1 continuous-mode technology. IEEE Trans Circ Syst I Regul Pap, 70 (7): 2651- 2664.

[26] Xie JE , Cheng KKM , Yu PY , et al., 2024. Dual-band pseudo-Doherty load modulated balanced amplifier design with arbitrarily selected frequency bands. IEEE Trans Circ Syst II Express Briefs, 71 (8): 3665- 3669.

[27] Zeng BH , Pan YF , Yuan FC , et al., 2025. Input phase controlled Doherty power amplifier with out-phased current load modulation for arbitrary output back-off. IEEE Trans Circ Syst I Regul Pap, 72 (6): 2626- 2638.

[28] Zhang ZW , Cheng ZQ , Li H , et al., 2020. A broadband Doherty power amplifier with hybrid class-EFJ mode. IEEE Trans Circ Syst I Regul Pap, 67 (12): 4270- 4280.

[29] Zheng SY , Liu ZW , Pan YM , et al., 2016. Bandpass filtering Doherty power amplifier with enhanced efficiency and wideband harmonic suppression. IEEE Trans Circ Syst I Regul Pap, 63 (3): 337- 346.

[30] Zhou XY , Zheng SY , Chan WS , et al., 2017. Broadband efficiency-enhanced mutually coupled harmonic postmatching Doherty power amplifier. IEEE Trans Circ Syst I Regul Pap, 64 (7): 1758- 1771.

Rights & permissions

The Authors. Published by Zhejiang University Press Co., Ltd.