對於射頻收發器系統來說，功率放大器扮演著相當重要的角色，為了達到高輸出功率與高效率，現今，功率放大器的設計以砷化鎵製程(GaAs process)為主。近年來隨著CMOS的進步，射頻電路大部份已經成功整合至CMOS 製程當中，且CMOS具有低功率消耗、低成本、高整合度的優勢，因此本論文將設計及實現三個使用不同功率合成技術的X頻帶互補式金氧半功率放大器。
第一個電路為變壓器功率合成技術之X頻段功率放大器，藉由變壓器實現功率合成而達到較高的輸出功率，量測增益("S" _"21" )為14.189 dB，飽和輸出功率("P" _"sat" )為24.74 dBm，1dB增益壓縮輸出功率(〖"OP" 〗_"1dB" )為16.63 dBm，最高功率附加效率(PAE)為19.9 %，晶片佈局面積為0.56 mm^2。
第二個電路為串聯結合變壓器功率合成技術之X頻段功率放大器，藉由堆疊每一功率元件的電壓，進而抬高整體的輸出電壓及功率，量測增益("S" _"21" )為13.08 dB，飽和輸出功率("P" _"sat" )為26.3 dBm，1dB增益壓縮輸出功率(〖"OP" 〗_"1dB" )為23.3 dBm，最高功率附加效率(PAE)為12.6 %，晶片佈局面積為1.08 mm^2，。
第三個電路為基於變壓器的電流合成技術之X頻段功率放大器，將兩組功率放大器元件直接並聯，藉此提高輸出功率，量測增益("S" _"21" )為13.4 dB，並達到27.3 dBm的飽和輸出功率("P" _"sat" )，23.84 dBm的1dB增益壓縮輸出功率(〖"OP" 〗_"1dB" )及19 %的最高功率附加效率(PAE) ，晶片佈局面積為1.27 mm^2。

Power amplifier (PA) plays an important role in the RF transceiver. Generally, the radio frequency power amplifiers are implemented in GaAs technology for the higher power and efficiency. Recently, the RF circuits have been successfully integrated into the Complementary Metal-Oxide Semiconductor (CMOS) process and CMOS is attractive for low power consumption, low cost and systems-on-a-chip (SoC) applications. Therefore, this thesis designs and implements three X-band CMOS PAs using different power combining techniques.
First, an X-band CMOS PA with transformer power combining technique has been designed and implemented. To achieve the higher output power, we utilizing the transformer to implement the power combining. The PA achieves measured small-signal gain("S" _"21" ) is 14.189 dB and maximum saturation output power("P" _"sat" ) is 24.74 dBm. The measured output 1-dB compression point (〖"OP" 〗_"1dB" )is 16.63 dBm and peak power-added efficiency (PAE) is 19.9 %. The chip area is 0.56 mm^2.
Second, for higher output power and efficiency, an X-band CMOS PA using series combining transformer to accumulate the voltage of each power device for boosting the output voltage and power has been designed and fabricated. The PA demonstrates a "S" _"21" of 13.08 dB, "P" _"sat" of 26.3 dBm, 〖"OP" 〗_"1dB" of 23.3 dBm and peak PAE of 12.6 %. The chip area is 1.08 mm^2.
Finally, an X-band CMOS PA based on transformer utilizes current combining technique, utilizing the current to connect two pairs of power amplifier for higher output power. The PA demonstrates a "S" _"21" of 13.4 dB, "P" _"sat" of 27.3 dBm, 〖"OP" 〗_"1dB" of 23.84 dBm and peak PAE of 19 %. The chip area is 1.27 mm^2.

[1]G. Nikandish and A. Medi, “A Design Procedure for High-Efficiency and Compact-Size 5-10-W MMIC Power Amplifiers in GaAs pHEMT Technology,” IEEE Transactions on Microwave Theory and Techniques, vol. 61, no. 8, Aug. 2013.
[2]P.-S. Chi, Z.-M. Tasi, J.-L. Kuo, K.-Y. Lin, and H. Wang, “A X-band, 23.8-dBm fully integrated power amplifier with 25.8% PAE in 0.18-um CMOS technology,” in Proceeding of the 5th European Microwave Integrated Circuited Conference, pp. 436-439, 2010.
[3]B.-H. Ku, S.-H. Baek, and S. Hong, “A wideband transformer-coupled CMOS power amplifier for X-band multifunction chips,” IEEE Transactions on Microwave Theory and Techniques, vol. 59, no. 6, pp. 1599-1609, Jun. 2011.
[4]B. H. Ku, S.-H. Baek, and S. Hong, “A X-Band CMOS Power Amplifier with On-chip Transmission Line Transformers,” in Proceedings of IEEE Radio Frequency Integrated Circuits Conference, pp. 523-526, June 2008.
[5]P J. P. Comeau, E. W. Thoenes, A. Imhoff, and M. A. Morton, “X-band 24 dBm CMOS power amplifier with transformer power combining,” in SiRF Dig., Sep. 2010, pp. 49-52.
[6]H. Wang, C. Sideris, and A. Hajimiri, “A 5.2-to-13GHz class-AB CMOS power amplifier with a 25.2dBm peak output power at 21.6% PAE,” in Solid-State Circuits Conference Digest of Technical Papers (ISSCC), pp. 44-45, Feb. 2010.
[7]J.-H. Chen, R. Helmi, A. Y.-S. Jou, and S. Mohammadi, “A Wideband Power Amplifier in 45 nm CMOS SOI Technology for X Band Applications,” Microwave and Wireless Components Letters, vol. 23, no. 11, Nov. 2013.
[8]S. C. Cripps, RF Power Amplifiers for Wireless Communications, "2" ^"nd" ed., Artech House, 1999.
[9]G. Gonzalez, Microwave Transistor Amplifiers – Analysis and Design, "2" ^"nd" ed., Prentice Hall, 1996.
[10]D. M. Pozar, Microwave Engineering, "3" ^"rd" ed., Wiley, 2005.
[11]H. Wang, J. H. Tsai, K. Y. Lin, Z. M. Tsai, and T. W. Huang, “MM-Wave Integration and Combinations,” IEEE microwave magazine, pp. 49-57, July/Aug. 2012.
[12]I. Aoki, S. D. Kee, D. B. Rutledge, and A. Hajimiri, “Distributed active transformer─A new power-combining and impedance-transformation technique,” IEEE Transactions on Microwave Theory and Techniques, vol. 50, no. 1, pp. 316-331, Jan. 2002.
[13]I. Aoki, S. D. Kee, D. B. Rutledge, and A. Hajimiri, “Fully integrated CMOS power amplifier design using the distributed active-transformer architecture,” IEEE J. Solid-State Circuits, vol. 37, no. 3, pp. 371-383, Mar. 2002.
[14]W.-H. Lin, Y.-N. Jen, J.-H. Tsai, H.-C. Lu, and T.-W. Huang, “V-band fully-integrated CMOS LNA and DAT PA for 60GHz WPAN applications,” in IEEE European Microwave Conference (EuMC), Sept. 2010, pp. 284-287.
[15]Y.-N. Jen, J.-H. Tsai, T.-W. Huang, and H. Wang, “Design and analysis of a 55-71GHz compact and broadband distributed active transformer power amplifier in 90-nm CMOS process,” IEEE Transactions on Microwave Theory and Techniques, vol. 57, no. 7, pp. 1637-1646, Jul. 2009.
[16]葉景富，24-GHz CMOS射頻前端晶片及毫米波電路之研究設計，國立成功大學電腦與通信工程研究所碩士論文，民國98年7月
[17]C. Lu, A.-V. H. Pham, M. Shaw, and C. Saint, “Linearization of CMOS broadband power amplifiers through combined multigated transistors and capacitance compensation,” IEEE Transactions on Microwave Theory and Techniques, pp. 2053-2058, Oct. 2007.
[18]C.-C. Kuo, Y.-H. Lin, H.-C. Lu, and H. Wang, “A K-band compact fully integrated transformer power amplifier in 0.18-μm CMOS,” in IEEE Asia-Pacific Microwave Conference (APMC), Nov. 2013, pp. 597-599.
[19]B. Jin, J. Moon, C. Zhao, and B. Kim, “A 30.8-dBm wideband CMOS power amplifier with minimized supply fluctuation,” IEEE Transactions on Microwave Theory and Techniques, vol. 60, no. 6, pp. 1658-1666, Jun. 2012.
[20]K. H. An, Y. Kim, O. Lee, K. S. Yang, H. Kim, W. Woo, J. J. Chang, C.-H. Lee, H. Kim, and J. Laskar, “A monolithic voltage-boosting parallel-primary transformer structures for fully integrated CMOS power amplifier design,” IEEE Radio Frequency Integrated Circuits (RFIC) Symp., Jun. 2007, pp. 419-422.
[21]G. Liu, P. Haldi, T.-J. K. Liu, A. M. Niknejad, “Fully integrated CMOS power amplifier with efficiency enhancement at power back-off,” IEEE J. Solid-State Circuits, vol. 43, no. 3, pp. 600-609, Mar. 2008.
[22]D. Chowdhury, C. D. Hull, O. B. Degani, Y. Wang, and A. M. Niknejad, “A fully integrated dual-mode highly linear 2.4GHz CMOS power amplifier for 4G WiMax applications,” IEEE J. Solid-State Circuits, vol. 44, no. 12, pp. 3393-3402, Dec. 2009.
[23]E. Kaymaksut and P. Reynaert, “A 2.4GHz fully integrated doherty power amplifier using series combining transformer,” in Proceedings of the European Solid-State Circuits Conference (ESSCIRC), Seville, Sept. 2010, pp. 302-305.
[24]J.-F. Yeh, J.-H. Tsai, and T.-W. Huang, “A multi-mode 60-GHz power amplifier with a novel power combination technique,” IEEE Radio Frequency Integrated Circuits (RFIC) Symp., Jun. 2012, pp. 61-64.
[25]O. Lee, K. S. Yang, K. H. An, Y. Kim, H. Kim, J. J. Chang, W. Woo, C.-H. Lee, and J. Laskar, “A 1.8-GHz 2-Watt fully integrated CMOS push-pull parallel-combined power amplifier design,” IEEE Radio Frequency Integrated Circuits (RFIC) Symp., Jun. 2007, pp. 435-438.
[26]J. Kim, W. Kim, H. Jeon, Y.-Y. Huang, Y. Yoon, H. Kim, C.-H. Lee, and K. T. Kornegay, “A fully-integrated high-power linear CMOS power amplifier with a parallel-series combining transformer,” IEEE J. Solid-State Circuits, vol. 47, no. 3, pp. 599-614, Mar. 2012.
[27]K. Kim and C. Nguyen, ”A 16.5-28 GHz 0.18-μm BiCMOS Power Amplifier With Flat 19.4±1.2 dBm Output Power,” Microwave and Wireless Components Letters, vol. 24, no. 2, Feb. 2014.
[28]J.-F. Yeh, J.-H. Tsai, and T.-W. Huang, “A 60-GHz power amplifier design using dual-radial symmetric architecture in 90-nm low-power CMOS,” IEEE Transactions on Microwave Theory and Techniques, vol. 61, no. 3, pp. 1280–1290, Mar. 2013.
[29]A. Niknejad, D. Chowdhury and J. Chen, “Design of CMOS power amplifiers,” IEEE Transactions on Microwave Theory and Techniques, vol. 60, no. 6, pp. 1784-1796, June 2012.
[30]A. M. Nikinejad, Electromagnetics for High-Speed Analog and Digital Communication Circuit. Mar. 2007.