Citation: | Tao CAO, Youjiang LIU, Chun YANG, Jie ZHOU. Circuits Optimization and System Linearization for High Efficiency and Wideband Envelope Tracking Architecture[J]. Journal of Electronics & Information Technology, 2020, 42(3): 787-794. doi: 10.11999/JEIT190275 |
To improve bandwidth, efficiency and linearity of Envelope Tracking (ET) architecture, it is necessary to optimize the performance of envelope supply modulator and linearize nonlinear behavior of the ET system. The optimization procedure of the supply modulator is proposed based on the equivalent circuit model. The frequency compensation network is used to improve the bandwidth and linearity of the modulator circuit. An envelope enhanced memory polynomial digital pre-distortion model is introduced to address the nonlinear distortion of the ET system. The practical circuit mentioned above is fabricated and the overall experimental system is set up. Measurement results show that the ET PA at S-band obtains measured efficiency 61%, 54%, 44% and Error Vector Magnitude (EVM) 1% for 6.7 dB PAPR signals with 5 MHz/10 MHz/20 MHz modulation bandwidths, respectively. The ET system exhibits competitive bandwidth, efficiency and linearity, which verifies the proposed optimization and linearization methodology.
BALTEANU F, MODI H, ZHU Yu, et al. Envelope tracking system for high power applications in uplink 4G/5G LTE advanced[C]. 2018 Asia-Pacific Microwave Conference, Kyoto, Japan, 2018: 863–865. doi: 10.23919/APMC.2018.8617571.
|
SHI Weimin, HE Songbai, ZHU Xiaoyu, et al. Broadband continuous-mode doherty power amplifiers with noninfinity peaking impedance[J]. IEEE Transactions on Microwave Theory and Techniques, 2018, 66(2): 1034–1046. doi: 10.1109/TMTT.2017.2749224
|
HOLZER K D, YUAN Wen, and WALLING J S. Wideband techniques for outphasing power amplifiers[J]. IEEE Transactions on Circuits and Systems I: Regular Papers, 2018, 65(9): 2715–2725. doi: 10.1109/TCSI.2018.2800041
|
LIU Youjiang, YOO C S, FAIRBANKS J, et al. A 53% PAE envelope tracking GaN power amplifier for 20 MHz bandwidth LTE signals at 880 MHz[C]. 2016 IEEE Topical Conference on Power Amplifiers for Wireless and Radio Applications, Austin, USA, 2016: 30–32. doi: 10.1109/PAWR.2016.7440155.
|
HASSAN M, ASBECK P M, and LARSON L E. A CMOS dual-switching power-supply modulator with 8% efficiency improvement for 20 MHz LTE envelope tracking RF power amplifier[C]. 2013 IEEE International Solid-State Circuits Conference Digest of Technical Papers, San Francisco, USA, 2013: 366–368. doi: 10.1109/ISSCC.2013.6487772.
|
KOMATSUZAKI Y, LANFRANCO S, KOLMONEN T, et al. A high efficiency 3.6–4.0 GHz envelope-tracking power amplifier using GaN soft-switching buck-converter[C]. 2018 IEEE/MTT-S International Microwave Symposium, Philadelphia, USA, 2018: 465–468. doi: 10.1109/MWSYM.2018.8439225.
|
HASSAN M, LARSON L E, LEUNG V W, et al. A wideband CMOS/GaAs HBT envelope tracking power amplifier for 4G LTE mobile terminal applications[J]. IEEE Transactions on Microwave Theory and Techniques, 2012, 60(5): 1321–1330. doi: 10.1109/TMTT.2012.2187537
|
KIM J, KIM D, CHO Y, et al. Highly efficient RF transmitter over broad average power range using multilevel envelope-tracking power amplifier[J]. IEEE Transactions on Circuits and Systems I: Regular Papers, 2015, 62(6): 1648–1657. doi: 10.1109/TCSI.2015.2423771
|
WANG Yazhou, JIN Qian, and RUAN Xinbo. Optimized design of the multilevel converter in series-form switch-linear hybrid envelope-tracking power supply[J]. IEEE Transactions on Industrial Electronics, 2016, 63(9): 5451–5460. doi: 10.1109/TIE.2016.2565459
|
JIN Qian, RUAN Xinbo, REN Xiaoyong, et al. Step-wave switched capacitor converter for compact design of envelope tracking power supply[J]. IEEE Transactions on Industrial Electronics, 2017, 64(12): 9587–9591. doi: 10.1109/TIE.2017.2716900
|
LENG Yang, RUAN Xinbo, JIN Qian, et al. High-efficiency high-bandwidth switch-linear hybrid envelope-tracking power supply with slew rate split-band method[C]. 2017 IEEE Energy Conversion Congress and Exposition, Cincinnati, USA, 2017: 2246–2252. doi: 10.1109/ECCE.2017.8096438.
|
JING Yue and BAKKALOGLU B. A high slew-rate adaptive biasing hybrid envelope tracking supply modulator for LTE applications[J]. IEEE Transactions on Microwave Theory and Techniques, 2017, 65(9): 3245–3256. doi: 10.1109/TMTT.2017.2678476
|
XI Huan, CAO Juan, LIU Ning, et al. High bandwidth envelope tracking power supply with pulse edge independent distribution method[J]. IEEE Transactions on Industrial Electronics, 2019, 66(8): 5907–5917. doi: 10.1109/TIE.2018.2874580
|
KIM D, KANG D, CHOI J, et al. Optimization for envelope shaped operation of envelope tracking power amplifier[J]. IEEE Transactions on Microwave Theory and Techniques, 2011, 59(7): 1787–1795. doi: 10.1109/TMTT.2011.2140124
|
LEACH W M. Feedforward compensation of the amplifier output stage for improved stability with capacitive loads[J]. IEEE Transactions on Consumer Electronics, 1988, 34(2): 334–338. doi: 10.1109/30.2950
|
MKADEM F, ISLAM A, and BOUMAIZA S. Multi-band complexity reduced generalized-memory-polynomial power-amplifier digital pre-distortion[J]. IEEE Transactions on Microwave Theory and Techniques, 2016, 64(6): 1763–1774. doi: 10.1109/TMTT.2016.2561279
|