@article{e5661267211940ff9e9531d55a125594,
title = "A SiGe envelope-tracking power amplifier with an integrated CMOS envelope modulator for mobile WiMAX/3GPP LTE transmitters",
abstract = "This paper presents a SiGe envelope-tracking (ET) cascode power amplifier (PA) with an integrated CMOS envelope modulator for mobile WiMAX and 3GPP long-term evolution (LTE) transmitters (TXs). The entire ET-based RF PA system delivers the linear output power of 22.3/24.3 dBm with the overall power-added efficiency of 33%/42% at 2.4 GHz for the WiMAX 64 quadrature amplitude modulation (64QAM) and the 3GPP LTE 16 quadrature amplitude modulation, respectively. Additionally, it exhibits a highly efficient broadband characteristic for multiband applications. Compared to the conventional fixed-supply cascode PA, our ET-based cascode PA meets the WiMAX/LTE spectral mask and error vector magnitude spec at close to its P1dB compression without the need of predistortion. The SiGe PA and the CMOS envelope modulator are both designed and fabricated in the TSMC 0.35-μm SiGe BiCMOS process on the same die. This study represents an essential integration step toward achieving a fully monolithic large-signal ET-based TX for wideband wireless applications.",
keywords = "Differential cascode power amplifier (PA), SiGe BiCMOS, WiMAX, envelope tracking (ET), high efficiency, linear-assisted switching envelope modulator, long-term evolution (LTE)",
author = "Yan Li and Jerry Lopez and Wu, {Po Hsing} and Weibo Hu and Ruili Wu and Lie, {Donald Y.C.}",
note = "Funding Information: ACKNOWLEDGMENT The authors are deeply grateful to the Industrial Technology Research Institute (ITRI), Hsinchu, Taiwan, and TSMC, Hsinchu, Taiwan, for integrated circuit (IC) fabrication. The authors would like to thank Dr. K. Chen, S. Wu and T.-Y. Yang, all with ITRI, for their valuable suggestions and discussions on the test bench setup. The authors would also like to thank Dr. K.-S. Lu, CEO of Diodes Inc., Plano, TX, for generously contributing and setting up the Keh-Shew Lu Regents Endowment Fund at Texas Tech University (TTU), together with the kind contributions from C. S. Lee, M. Chiang, and J. England (all formerly with Texas Instruments Incorporated), and the TTU Board of Regents. The authors would also like to thank Dr. K.-S. Lu for underwriting the National Cheng-Kung University (NCKU)–TTU dual-degree exchange program sponsored by Diodes Inc. The authors also extend thanks to Prof. T. J. Liang, Prof. P.-C. Chung, and various faculty members of the Department of Electrical Engineering, NCKU, Tainan, Taiwan, for their kind support of the NCKU–TTU dual-degree exchange program. Funding Information: Manuscript received March 02, 2011; revised July 08, 2011; accepted July 28, 2011. Date of publication September 15, 2011; date of current version October 12, 2011. This work was supported by the Industrial Technology Research Institute (ITRI), Taiwan.",
year = "2011",
doi = "10.1109/TMTT.2011.2164550",
language = "English",
volume = "59",
pages = "2525--2536",
journal = "IEEE Transactions on Microwave Theory and Techniques",
issn = "0018-9480",
publisher = "IEEE",
number = "10 PART 1",
}