本論文主要是探討類循環器與次諧波混頻器，其研究方向著重於發展寬頻、高隔離度之新穎電路架構。
近年來，由於製程技術進步，使得微波及毫米波之單晶積體電路之高頻特性有顯著的提升，透過III-V化合物半導體製程所製作之主、被動元件，具有優異的電性，其中Schottky 二極體相當適用於被動混頻器之設計，因此採用0.15-μm pHEMT製程技術來實現各式新穎V頻帶之次諧波混頻器。此外，在現今微波及毫米波裡，單一晶片系統 (SOC) 整合天線、射頻區塊與基頻區塊的類比、數位電路以為主流，其中矽製程技術具有極佳的積體整合度與低製作成本，然而受限於主動元件之低崩潰電壓，導致矽製程不利於高功率放大器之製作，因此目前主流依舊採 用單一封裝系統 (SIP) 為主，本論文中以提升積體整合度為目標，使用0.18-μm與90-nm CMOS 製程設計寬頻帶之新式次諧波混頻器與類循環器有其研究價值。
在X頻帶到F頻帶類循環器之設計上，本論文致力於寬頻與高隔離度之研發，提出新穎的設計概念針對操作頻寬、埠際隔離度、簡化佈局進行改良。在寬頻類循環器的設計上，本論文提出兩種改良架構，相較於傳統的設計，可提升頻寬至100 GHz 以上，其中一新穎的設計概念，利用分散式放大器的超寬頻特性與兩組藍吉耦合器的寬頻與高隔離度特性來達到超寬頻與高隔離度的類循環器電路，其中利用分散式放大器的不可逆性特性與藍吉耦合器來達到類循環器的單一方向性與不錯的埠與埠隔離度。本論文亦提出一新穎的類循環器架構，將分散式放大器疊接一組來建構一個巴倫電路，其巴倫電路擁有超寬頻、高的插入增益與低相位誤差/振幅誤差。使用巴倫電路疊接一組分散式放大器來達到超寬頻類循環器，利用巴倫電路的低相位誤差/振幅誤差與分散式放大器來產生訊號相位相消而達到高的隔離度。此外，分散式放大器的超寬頻特性、低雜訊與不可逆特性也充分被利用，因此類循環器可達到超寬頻，且大幅減小電路之面積，同時亦具有良好的埠際隔離度與低雜訊特性。
隨著操作頻率的提升，高Q 值之被動元件不易獲得，導致高功率輸出與低 相位雜訊之壓控振盪器設計難度增加，此時次諧波混頻器提供一個極佳解決方 案，傳統的次諧波混頻器由於電路架構上使用λLO/4 的開路與短路微帶線，不利寬頻操作，本論文使用一hairpin 多工器將RF訊號與LO訊號功率結合至並聯反接二極體對，並且可獲得54-66GHz 的寬頻特性，如此一來不僅提高 RF/LO 隔離度，且可有效的拓展操作頻寬，並達成微小化的目的。本論文亦提出一新穎的次諧波混頻器架構，其架構利用一改良類循環器來將這射頻與本振訊號結合輸入至gate pumped電晶體進行混頻，利用改良類循環器的單一方向性與高隔離度來達到相當高埠際隔離度，並可達到寬頻化的目的。最後，本論文提出一超寬頻次諧波混頻器，利用分散式放大器與並聯反接二極體對的超寬頻特性來達到K頻帶到F頻帶之混頻器，也利用分散式放大器的高插入增益、不可逆特性與低雜訊特性，使得超寬頻次諧波混頻器具有好的轉換損失、高的LO-to-RF隔離度與雜訊特性。
經由新架構的研發，本論文所設計的類循環器與次諧波混頻器已達成寬頻操作、埠技隔離度之改善與特性提升之要求。

This research focuses on the development of broadband and high isolation circuits, which include quasi-circulators and sub-harmonic mixers (SHMs).
For quasi-circulators, two novel design concepts using the 90-nm complementary CMOS technology are proposed to improve operation bandwidth and port-to-port isolations. In this dissertation, we present an ultra wideband quasi-circulator, which is composed of two distributed amplifiers and two Lange couplers to attain ultra wideband performance at 14 GHz to 67 GHz. The proposed quasi-circulator generates good insertion gain of 4.3 dB to -3.5 dB, low noise figure of 7.1 dB to 12.6 dB, and good isolation characteristic of |S31| better than 20 dB. Additionally, we also present a broadband active balun and its application to a quasi-circulator through a distributed amplifier. The proposed balun uses cascode distributed amplifier configuration to realize wide operation bandwidth of 10 GHz to 100 GHz, good insertion gain of -2.58 dB to 2.59 dB, low amplitude/phase error 0.76 dB/10°, and high P1dB of 7 dBm with a miniature chip dimension of 0.4 mm2. The other proposed quasi-circulator uses the proposed active balun and distributed amplifier to attain broad operation bandwidth at 10 GHz to 100 GHz, good insertion gain of 0.5 dB to 4.8 dB, and isolation of |S31| better than 23 dB. Using the distributed amplifier technique, the proposed quasi-circulators offers significant advantages of broad operation bandwidth, high isolation, low noise figure, and good insertion gain.
While the operating frequency increases, the Q-factor of passive elements will be degraded that is consequent on the degradation of output power and increase of phase noise of VCO. Subharmonic mixers can be a feasible solution to this problem, but conventional SHMs which use bothλLO/4 open and short stubs to enhance isolations, will cause a significant decrease in the operating bandwidth. Accordingly, we build a 54-66 GHz broadband sub-harmonic monolithic passive mixer using the standard 0.15 µm PHEMT process. This mixer uses the hairpin diplexer to improve the isolation between the RF and LO ports having a broadband operation. Based on the measured results with a conversion loss of 15.2-18.3 dB, the LO-to-RF isolation is found to be better than 23.5 dB. Additionally, we also present a 21 GHz to 40 GHz broadband subharmonic gate-pumped mixer using the standard 0.18 µm CMOS process. A modified quasi-circulator is monolithically integrated with an nMOS field-effect transistor to perform down-converter mixing while enhancing all port isolations through a broadband operation. The measured results reflect a low conversion loss of 8.3 dB to 14.2 dB, a LO-to- RF isolation greater than 50 dB, and a high 2LO-to-RF isolation of 48 dB to 65 dB over the 21 GHz to 40 GHz RF bandwidth at a 10.5 dBm LO power level. Finally, a Ka- to F-band ultra-broadband SHM using the standard 90-nm CMOS process is demonstrated. The proposed SHM uses a distributed amplifier and anti-parallel diode pair configuration to realize wide operation bandwidth of 33 GHz to 103 GHz, low conversion loss of 0.52 dB to 3.35 dB, good LO-to- RF isolation greater than 27.7 dB, and high 2LO-to-RF isolation better than 60 dB with a miniature chip dimension of 0.49 mm2 at a 10 dBm LO power level.
Through the development of the novel architectures, the proposed quasi-circulators and mixers, which have broadband operation and superior port-to-port isolations, can significantly improve performances.

Chapter 1
[1] I. Bahl, and P. Bhartia, Microwave solid state circuit design, Wiley-Interscience, 2003.
[2] W. R. Deal, X. B. Mei, V. Radisic, W. Yoshida, P. H. Liu, J. Uyeda, M. Barsky, T. Gaier, A. Fung, and R. Lai, “Demonstration of a S-MMIC LNA with 16-dB Gain at 340-GHz,” in Proc. Compound Semiconductor Integrated Circuits Symp., Oct. 2007, pp. 1–4.
[3] O. S. A. Tang, K. H. G. Duh, S. M. J. Liu, P. M. Smith, W. F. Kopp, T. J. Rogers, and D. J. Pritchard, “Design of high-Power, high-efficiency 60-GHz MMICs using an improved nonlinear PHEMT model,” IEEE J. Solid-State Circuits, vol. 32, pp. 1326-1333, Sept. 1997.
[4] F. Colomb, and A. Platzker, “A 3-Watt Q-band GaAs pHEMT power amplifier MMIC for high temperature operation,” in IEEE MTT-S Int. Microw. Symp. Dig., June 2006, pp. 897-900.
[5] C. H. Lin, H. Z. Liu, C. K. Chu, H. K. Huang, C. C. Liu, C. H. Chang, C. L. Wu, C. S. Chang, and Y. H. Wang, “A compact 6.5 W PHEMT MMIC power amplifier for Ku-band applications,” IEEE Microw. Wireless Compon. Lett., vol.17, no. 2, pp. 154-156, Feb. 2007.
[6] H. Z. Liu, C. H. Lin, C. K. Chu, H. K. Huang, M. P. Houng, C. H. Chang, C. L. Wu, C.S. Chang, and Y. H. Wang, “A single-supply Ku-band 1-Watt power amplifier MMIC with compact self-bial PHEMTs,” IEEE Microw. Wireless Compon. Lett., ol.16, no. 6, pp. 330-332, June 2006.
[7] Q. Sun, L. Krishnamurthy, V. T. Vo and A. A. Rezazadeh, “Compact inductors and baluns using multilayer technology,” in EMRS DTC Technical Conference, 2006.
[8] K. Nishikawa, B. Piernas, T. Nakagawa, K. Araki, and K. Cho, “V-band fully integrated TX/RX single-chip 3-D MMICs using commercial GaAs pHEMT technology for high speed wireless application,” in GaAs IC Symp. Dig., 2003, pp. 97–100.
[9] H. Hirano, K. Nishikawa, I. Toyoda, S. Aoyama, S. Sugitani, and K. Yamasaki, “Three-dimensional passive circuit technology for ultra-compact MMICs,” IEEE Trans. Microw. Theory Tech., vol. 43, pp. 2845–2850, Dec. 1995.
[10] T. Tokumitsu, N. Hirano, K. Yamasaki, C. Yamaguchi, K. Nishikawa, and M. Aikawa, “Highly integrated three-dimensional MMIC technology applied to novel masterslice GaAs- and Si-MMICs,” IEEE J. Solid-State Circuits, vol. 32, pp. 1334–1341, Sept. 1997.
[11] K. Nishikawa, K. Kamogawa, B. Piernas, M. Tokumitsu, S. Sugitani, I. Toyoda, and K. Araki, “Three-dimensional MMIC technology for low-cost millimeter-wave MMICs,” IEEE J. Solid-State Circuits, vol. 36, pp. 1351–1359, Sept. 2001.
[12] I. S. Ishak, R. A. Keating, and C. K. Chakrabarty, “RF substrate noise characterization for CMOS 0.18 μm,” in Proc. RF and Microwave Conf., 2004, pp. 60–63.
[13] D. M. Pozar, Microwave and RF design of wireless systems, John Wiley & Sons Inc., 2000.
[14] S. Hara, T. Tokumitsu, and M. Aikawa, “Novel unilateral circuits for MMIC circulators,” IEEE Trans. Microw. Theory Tech., vol. 38, no. 10, pp. 1399–1406, Oct. 1990.
[15] G. Carchon and B. Nauwelaers, “Power and noise limitation of active circulators,” IEEE Trans. Microw. Theory Tech., vol. 48, no. 2, pp. 316–319, Feb. 2000.
[16] C. Kalialakis, M. J. Cryan, P. S. Hall, and P. Gardner, “Analysis and design of integrated active circulator antennas,” IEEE Trans. Microw. Theory Tech., vol. 48, no. 6, pp. 1017–1023, Jun. 2000.
[17] C. Saavedra and Y. Zheng, “Active quasi-circulator realization with gain elements and slow-wave couplers,” IET Microw. Antennas, Propag., vol. 1, no. 5, pp. 1020–1023, 2007.
[18] S. C. Shin, J. Huang, K. Lin, and H. Wang, “A 1.5–9.6 GHz monolithic active quasi-circulator in 0.18 μm CMOS technology,” IEEE Microw. Wireless Compon. Lett., vol. 18, no. 12, pp. 797–799, Dec. 2008.
[19] A. Gasmi, B. Huyart, E. Beregeault, and L. Jallet, “Noise and power optimization of a MMIC quasi-circulator,” IEEE Trans. Microw. Theory Tech., vol. 45, no. 9, pp. 1572–1577, Sep. 1997.
[20] S. W. Y. Mung and W. S. Chan, “Novel active quasi-circulator with phase compensation technique,” IEEE Microw. Wireless Compon. Lett., vol. 18, no. 12, pp. 800–802, Dec. 2008.
[21] Y. Zheng and C. E. Saavedra, “Active quasi-circulator MMIC using OTAs,” IEEE Microw. Wireless Compon. Lett., vol. 19, no. 4, pp. 218–220, Apr. 2009.
[22] S. K. Cheung, T. Halloran, W. Weedon, and C. Caldwell, “MMIC-based quadrature hybrid quasi-circulators for simultaneous transmit and receive,” IEEE Trans. Microw. Theory Tech., vol. 58, no. 3, pp. 489–497, Mar. 2010.
[23] H. S. Wu, C. W. Wang, and C. K. Clive Tzuang, “CMOS active quasi-circulator with dual transmission gains incorporating feedforward technique at K-Band,” IEEE Trans. Microw. Theory Tech., vol. 58, no. 8, pp. 2084–2091, Aug. 2010.
[24] R. Svitek, and S. Raman, “5–6 GHz SiGe active I/Q subharmonic mixers with power supply noise effect characterization,” IEEE Microw. Wireless Compon. Lett., vol. 14, no. 7, pp. 319–321, July 2004.
[25] J. Y. Su, C. Meng, and P. Y. Wu, “Q-Band pHEMT and mHEMT subharmonic Gilbert upconversion mixers,” IEEE Microw. Wireless Compon. Lett., vol. 19, no. 6, pp. 392–394, June 2009.
[26] M. Cohn, J. E. Degenford, and B. A. Newman, “Harmonic mixing with an anti parallel diode pair,” IEEE Trans. Microw. Theory Tech., vol. MTT-23, no. 8, pp. 667–673, Aug. 1975.
[27] C. H. Lin, Y. A. Lai, J. C. Chiu, and Y. H. Wang, “A 23–37 GHz miniature MMIC subharmonic mixer,” IEEE Microw. Wireless Compon. Lett., vol. 17, no. 9, pp. 679–681, Sep. 2007.
[28] C. M. Lin, H. K. Lin, Y. A. Lai, C. P. Chang, and Y. H. Wang, “A 10–40 GHz broadband subharmonic monolithic mixer in 0.18 μm CMOS technology,” IEEE Microw. Wireless Compon. Lett., vol. 19, no. 2, pp. 95–97, Feb. 2009.
[29] M. Bao, H. Jacobsson, L. Aspemyr, G. Carchon, and X. Sun, “A 9–31-GHz subharmonic passive mixer in 90-nm CMOS technology,” IEEE J. Solid-State Circuits, vol. 41, no. 10, pp. 2257–2264, Oct. 2006.
[30] Y. Sun and C. J. Scheytt, “A 122 GHz sub-harmonic mixer with a modified APDP topology for IC integration,” IEEE Microw. Wireless Compon. Lett., vol. 21, no.12, pp. 679–681, Dec. 2011.
[31] Y. Zhao, E. Öjefors, K. Aufinger, T. F. Meister, and U. R. Pfeiffer, “A 160-GHz subharmonic transmitter and receiver chipset in an SiGe HBT technology,” IEEE Trans. Microw. Theory Tech., vol. 60, no. 10, pp. 3286–3299, Oct. 2012.
[32] T. Y. Yang and H. K. Chiou, “A 28 GHz sub-harmonic mixer using LO doubler in 0.18-μm CMOS technology,” IEEE Radio Frequency Integrated Circuits (RFIC) Symp., San Francisco, CA, June, 2006, pp. 209–212.
[33] S. K. Lin, J. L. Kuo, and H. Wang, “A 60 GHz sub-harmonic resistive FET mixer using 0.13μm CMOS technology,” IEEE Microw. Wireless Compon. Lett., vol. 21, no. 10, pp. 562–564, Oct. 2011.
[34] P. C. Yeh, W. C. Liu, and H. K. Chiou, “Compact 28-GHz subharmonically pumped resistive mixer MMIC using a lumped-element high-pass/band-pass balun,” IEEE Microw. Wireless Compon. Lett., vol. 15, no. 2, pp. 62–64, Feb. 2005.
[35] H. K. Chiou and J. Y. Lin, “Symmetric offset stack balun in standard 0.13-μm CMOS technology for three broadband and low-loss balanced passive mixer designs,” IEEE Trans. Microw. Theory Tech., vol. 59, no. 6, pp. 1529–1538, June 2011.
[36] S. E. Gunnarsson, “Analysis and design of a novel ×4 subharmonically pumped resistive HEMT mixer,” IEEE Trans. Microw. Theory Tech., vol. 56, no. 4, pp. 809–816, Apr. 2008.
[37] Y. J. Hwang, H. Wang, and T. H. Chu, “A W-band subharmonically pumped monolithic GaAs-based HEMT gate mixer,” IEEE Microw. Wireless Compon. Lett., vol. 14, no. 7, pp. 313–315, July 2004.
[38] S. He and C. E. Saavedra, “An ultra-low-voltage and low-power ×2 subharmonic downconverter mixer,” IEEE Trans. Microw. Theory Tech., vol. 60, no. 2, pp. 311–317, Feb. 2012.
[39] T. K. Johansen, J. Vidkjær, V. Krozer, A. Konczykowska, M. Riet, F. Jorge, and T. Djurhuus, “A high conversion-gain Q-band InP DHBT subharmonic mixer using LO frequency doubler,” IEEE Trans. Microw. Theory Tech., vol. 56, no. 3, pp. 613–619, Mar. 2008.
[40] S. Raman, F. Rucky, and G. M. Rebeiz, “A high-performance W-band uniplanar subharmonic mixer,” IEEE Trans. Microw. Theory Tech., vol. 45, no. 6, pp. 955–962, Jun. 1997.
[41] O. Habibpour, J. Vukusic, and J. Stake, “A 30-GHz integrated subharmonic mixer based on a multichannel graphene FET,” IEEE Trans. Microw. Theory Tech., vol. 61, no. 2, pp. 841–847, Feb. 2013.
[42] S. H. Hung, Y. C. Lee, C. C. Su, and Y. H. Wang, “High-isolation millimeter-wave subharmonic monolithic mixer with modified quasi-circulator,” IEEE Trans. Microw. Theory Tech., vol. 61, no. 3, pp. 1140–1149, Mar. 2013.
[43] C. L. Kuo., C. C. Kuo, C. H. Lien, J. H. Tsai, and H. Wang, “A novel reduced-size rat-race broadside coupler and its application for CMOS distributed sub-harmonic mixer,” IEEE Microw. Wireless Compon. Lett., vol. 18, no.3, pp. 194–196, Mar. 2008.

Chapter 2
[1] S. Hara, T. Tokumitsu, and M. Aikawa, “Novel unilateral circuits for MMIC circulators,” IEEE Trans. Microw. Theory Tech., vol. 38, no. 10, pp. 1399–1406, Oct. 1990.
[2] G. Carchon and B. Nauwelaers, “Power and noise limitation of active circulators,” IEEE Trans. Microw. Theory Tech., vol. 48, no. 2, pp. 316–319, Feb. 2000.
[3] C. Kalialakis, M. J. Cryan, P. S. Hall, and P. Gardner, “Analysis and design of integrated active circulator antennas,” IEEE Trans. Microw. Theory Tech., vol. 48, no. 6, pp. 1017–1023, Jun. 2000.
[4] C. Saavedra and Y. Zheng, “Active quasi-circulator realization with gain elements and slow-wave couplers,” IET Microw. Antennas, Propag., vol. 1, no. 5, pp. 1020–1023, 2007.
[5] S. C. Shin, J. Huang, K. Lin, and H. Wang, “A 1.5–9.6 GHz monolithic active quasi-circulator in 0.18 μm CMOS technology,” IEEE Microw. Wireless Compon. Lett., vol. 18, no. 12, pp. 797–799, Dec. 2008.
[6] A. Gasmi, B. Huyart, E. Beregeault, and L. Jallet, “Noise and power optimization of a MMIC quasi-circulator,” IEEE Trans. Microw. Theory Tech., vol. 45, no. 9, pp. 1572–1577, Sep. 1997.
[7] S. W. Y. Mung and W. S. Chan, “Novel active quasi-circulator with phase compensation technique,” IEEE Microw. Wireless Compon. Lett., vol. 18, no. 12, pp. 800–802, Dec. 2008.
[8] Y. Zheng and C. E. Saavedra, “Active quasi-circulator MMIC using OTAs,” IEEE Microw. Wireless Compon. Lett., vol. 19, no. 4, pp. 218–220, Apr. 2009.
[9] S. K. Cheung, T. Halloran, W. Weedon, and C. Caldwell, “MMIC-based quadrature hybrid quasi-circulators for simultaneous transmit and receive,” IEEE Trans. Microw. Theory Tech., vol. 58, no. 3, pp. 489–497, Mar. 2010.
[10] H. S. Wu, C. W. Wang, and C. K. Clive Tzuang, “CMOS active quasi-circulator with dual transmission gains incorporating feedforward technique at K-Band,” IEEE Trans. Microw. Theory Tech., vol. 58, no. 8, pp. 2084–2091, Aug. 2010.
[11] Y. Ayasli, R. L. Mozzi, J. L. Vorhaus, L. D. Reynolds, and R. A. Pucel, “A monolithic GaAs 1-13 GHz traveling-wave amplifier,” IEEE Trans. Microw. Theory Tech., vol. 30, no. 7, pp. 976–981, July 1982.
[12] M. Palomba, A. Bentini, D. Palombini, W. Ciccognani, and E. Limiti, “A novel hybrid active quasi-circulator for L-band applications,” Microwave Radar and Wireless Communications , Warsaw, Poland, May, 2012, pp. 41–44.
[13] D. J. Huang, J. L. Kuo, and H. Wang, “A 24-GHz low power and high isolation active quasi-circulator,” 2012 IEEE Microwave Symposium Digest MTT-S, Montreal, QC, Canada, June, 2012, pp. 1–3.
[14] S. He, N. Akel, and C.E. Saavedra, “Active quasi-circulator with high port-to-port isolation and small area,” Electronics Lett., vol. 48, no.14, pp. 848–850, July 2012.
[15] C. H. Chang, Y. T. Lo, and J. F. Kiang, “A 30 GHz active quasi-circulator with current-reuse technique in 0.18 μm CMOS technology,” IEEE Microw. Wireless Compon. Lett., vol. 20, no.12, pp. 693–695, Dec. 2012.
[16] H. K. Chiou and J. Y. Lin, “Symmetric offset stack balun in standard 0.13-μm CMOS technology for three broadband and low-loss balanced passive mixer designs,” IEEE Trans. Microw. Theory Tech., vol. 59, no. 6, pp. 1529–1538, June 2011.
[17] H. H. Chiang, F. C. Huang, C. S. Wang, and C. K. Wang, “A 63 GHz low-noise active balun with broadband phase- correction technique in 90 nm CMOS,” in Proc. IEEE Asian Solid-State Circuits Conf. (A-SSCC), 2010, pp. 289–292.
[18] T. T. Hsu and C. N. Kuo, “Low power 8-GHz ultra-wideband active balun,” in Silicon Monolith. Integr. Circuits RF Syst. Dig., Jan. 2006, pp. 18–20.
[19] K. Jung, W. R. Eisenstadt, R. M. Fox, A. W. Ogden, and J. Yoon, “Broadband active balun using combined cascode-cascade configuration,” IEEE Trans. Microw. Theory Tech., vol. 56, no. 8, pp. 1790–1796, Aug. 2008.
[20] C. Viallon, D. Venturin, J. Graffeuil, and T. Parra, “Design of an original K-band active balun with improved broadband balanced behavior,” IEEE T-MTT, vol. 15, pp. 280–282, Apr. 2005.
[21] B. J. Huang, B. J. Huang, K. Y. Lin, and H. Wang, “A 2–40 GHz active balun using 0.13 um CMOS process,” IEEE Microw. Wireless Compon. Lett., vol. 19, no. 3, pp. 164–166, Mar. 2009.
[22] A. H. Baree and I. D. Robertson, “Monolithic MESFET distributed baluns based on the distributed amplifier gate-line termination technique,” IEEE Trans. Microw. Theory Tech., vol. 45, no. 2, pp. 118–195, Feb. 1997.
[23] M. D. Tsai, K. L. Deng, H. Wang, C. H. Chen, C. S. Chang, and John G. J. Chern, “A miniature 25-GHz 9-dB CMOS cascaded single-stage distributed amplifier,” IEEE Microw. Wireless Compon. Lett., vol. 14, no. 12, pp. 554–556, Dec. 2004.
[24] S. H. Weng, H. Y. Chang, and C. C. Chiong, “A DC-21 GHz low imbalance active balun using Darlington cell technique for high speed data communications,” IEEE Microw. Wireless Compon. Lett., vol. 19, no. 11, pp. 728–730, Nov. 2009.

Chapter 3
[1] M. Cohn, J. E. Degenford, and B. A. Newman, “Harmonic mixing with an anti parallel diode pair,” IEEE Trans. Microw. Theory Tech., vol. MTT-23, no. 8, pp. 667–673, Aug. 1975.
[2] C. H. Lin, Y. A. Lai, J. C. Chiu, and Y. H. Wang, “A 23–37 GHz miniature MMIC subharmonic mixer,” IEEE Microw. Wireless Compon. Lett., vol. 17, no. 9, pp. 679-681, Sep. 2007.
[3] C. M. Lin, H. K. Lin, Y. A. Lai, C. P. Chang, and Y. H. Wang, “A 10–40 GHz broadband subharmonic monolithic mixer in 0.18 μm CMOS technology,” IEEE Microw. Wireless Compon. Lett., vol. 19, no. 2, pp. 95-97, Feb. 2009.
[4] C. L. Kuo., C. C. Kuo, C. H. Lien, J. H. Tsai, and H. Wang, “A novel reduced-size rat-race broadside coupler and its application for CMOS distributed sub-harmonic mixer,” IEEE Microw. Wireless Compon. Lett., vol. 18, no.3, pp. 194-196, Mar. 2008.
[5] M. Bao, H. Jacobsson, L. Aspemyr, G. Carchon, and X. Sun, “A 9–31-GHz subharmonic passive mixer in 90-nm CMOS technology,” IEEE J. Solid-State Circuits, vol. 11, no. 10, pp. 2257–2264, Oct. 2006.
[6] T. Y. Yang and H. K. Chiou, “A 28 GHz sub-harmonic mixer using LO doubler in 0.18-μm CMOS technology,” IEEE Radio Frequency Integrated Circuits (RFIC) Symp., San Francisco, CA, June 2006, pp. 209–212.
[7] S. K. Lin, J. L. Kuo, and H. Wang, “A 60 GHz sub-harmonic resistive FET mixer using 0.13μm CMOS technology,” IEEE Microw. Wireless Compon. Lett., vol. 21, no. 10, pp. 562-564, Oct. 2011.
[8] P. C. Yeh, W. C. Liu, and H. K. Chiou, “Compact 28-GHz subharmonically pumped resistive mixer MMIC using a lumped-element high-pass/band-pass balun,” IEEE Trans. Microw. Wireless Compon. Lett., vol. 15, no. 2, pp. 62–64, Feb. 2005.
[9] H. K. Chiou and J. Y. Lin, “Symmetric offset stack balun in standard 0.13-μm CMOS technology for three broadband and low-loss balanced passive mixer designs,” IEEE Trans. Microw. Theory Tech., vol. 59, no. 6, pp. 1529–1538, June 2011.
[10] S. E. Gunnarsson, “Analysis and design of a novel ×4 subharmonically pumped resistive HEMT mixer,” IEEE Trans. Microw. Theory Tech., vol. 56, no. 4, pp. 809–816, Apr. 2008.
[11] Y. J. Hwang, H. Wang, and T. H. Chu, “A W-band subharmonically pumped monolithic GaAs-based HEMT gate mixer,” IEEE Microw. Wireless Compon. Lett., vol. 14, no. 7, pp. 313–315, Jul. 2004.
[12] M. W. Medley, Microwave and RF Circuits: Analysis, Synthesis, and Design, Artech House, Inc., Norwood, MA, 1992.
[13] S. Hara, T. Tokumitsu, and M. Aikawa, “Novel Unilateral Circuits for MMIC Circulators,” IEEE Trans. Microwave Theory Tech., Vol. 38, pp. 1399-1405, Oct. 1990.
[14] S. He and C. E. Saavedra, “An ultra-low-voltage and low-power ×2 subharmonic downconverter mixer,” IEEE Trans. Microw. Theory Tech., vol. 60, no. 2, pp. 311–317, Feb. 2012.
[15] T. K. Johansen, J. Vidkjær, V. Krozer, A. Konczykowska, M. Riet, F. Jorge, and T. Djurhuus, “A high conversion-gain Q-band InP DHBT subharmonic mixer using LO frequency doubler,” IEEE Trans. Microw. Theory Tech., vol. 56, no. 3, pp. 613–619, Mar. 2008.
[16] S. Raman et al., “A high-performance W-band uniplanar subharmonic mixer,” IEEE Trans. Microw. Theory Tech., vol. 45, no. 6, pp. 955–962, Jun. 1997.
[17] G. Carchon and B. Nauwelaers, “Power and noise limitation of active circulators,” IEEE Trans. Microw. Theory Tech., vol. 48, no. 2, pp. 316–319, Feb. 2000.
[18] S. Hara, T. Tokumitsu, and M. Aikawa, “Novel unilateral circuits for MMIC circulators,” IEEE Trans. Microw. Theory Tech., vol. 38, no. 10, pp. 1399–1406, Oct. 1990.
[19] C. Kalialakis, M. J. Cryan, P. S. Hall, and P. Gardner, “Analysis and design of integrated active circulator antennas,” IEEE Trans. Microw. Theory Tech., vol. 48, no. 6, pp. 1017–1023, Jun. 2000.
[20] C. Saavedra and Y. Zheng, “Active quasi-circulator realization with gain elements and slow-wave couplers,” IET Microw. Antennas, Propag., vol. 1, no. 5, pp. 1020–1023, 2007.
[21] S. C. Shin, J. Huang, K. Lin, and H. Wang, “A 1.5–9.6 GHz monolithic active quasi-circulator in 0.18 μm CMOS technology,” IEEE Microw. Wireless Compon. Lett., vol. 18, no. 12, pp. 797–799, Dec. 2008.
[22] A. Gasmi, B. Huyart, E. Beregeault, and L. Jallet, “Noise and power optimization of a MMIC quasi-circulator,” IEEE Trans. Microw. Theory Tech., vol. 45, no. 9, pp. 1572–1577, Sep. 1997.
[23] S. W. Y. Mung and W. S. Chan, “Novel active quasi-circulator with phase compensation technique,” IEEE Microw. Wireless Compon. Lett., vol. 18, no. 12, pp. 800–802, Dec. 2008.
[24] Y. Zheng and C. E. Saavedra, “Active quasi-circulator MMIC using OTAs,” IEEE Microw. Wireless Compon. Lett., vol. 19, no. 4, pp. 218–220, Apr. 2009.
[25] S. K. Cheung, T. Halloran, W. Weedon, and C. Caldwell, “MMIC-based quadrature hybrid quasi-circulators for simultaneous transmit and receive,” IEEE Trans. Microw. Theory Tech., vol. 58, no. 3, pp. 489–497, Mar. 2010.
[26] H. S. Wu, C. W. Wang, and C. K. Clive Tzuang, “CMOS active quasi-circulator with dual transmission gains incorporating feedforward technique at K-Band,” IEEE Trans. Microw. Theory Tech., vol. 58, no. 8, pp. 2084–2091, Aug. 2010.
[27] W. C. Chien, C. M. Lin, C. H. Liu, S. H. Hung, and Y.-H. Wang, “Wide-band high isolation subharmonically pumped resistive mixer with active quasi-circulator,” Progress in Electromagnetics Research Letters, Vol. 18, pp. 135–143, 2010.
[28] M. Kawashima, T. Nakagawa, and K. Araki, “A Novel Broadband Active Balun,” IEEE Microwave Conference 33rd, European, Oct, 2003, pp. 7–9.
[29] B. J. Huang, B. J. Huan, K. Y. Lin, and H. Wang, “A 2–40 GHz active balun using 0.13 μm CMOS process,” IEEE Microw. Wireless Compon. Lett., vol. 19, no. 3, pp. 164–166, Mar. 2009.
[30] T. T. Hsu and C. N. Kuo, “Low power 8-GHz ultra-wideband active balun”, Silicon Monolithic Integrated Circuits in RF Systems dig., pp., 18-20 Jan. 2006.
[31] C. Viallon, D. Venturin, J. Graffeuil, and T. Parra, “Design of an original K-band active balun with improved broadband balanced behavior,” IEEE Microw. Wireless Compon. Lett., vol.15, pp.280 – 282, April 2005.
[32] O. S. A. Tang and C. S Aitchison, “A very wide-band microwave MESFET mixer using the distributed mixing principle,” IEEE Trans. Microw. Theory Tech., vol. 33, no. 12, pp. 562–571, Dec. 1985.
[33] H. Y. Yang, J. H. Tsai, C. H. Wang, C. S. Lin, W. H. Lin, K. Y. Lin, T. W. Huang, and H. Wang, “Design and analysis of a 0.8–77.5-GHz ultra-broadband distributed drain mixer using 0.13-Ωm CMOS technology,” IEEE Trans. Microw. Theory Tech., vol. 57, no. 3, pp. 562–571, Mar. 2009.
[34] W. Jutzi, “A MESFET distributed amplifier with 2-GHz bandwidth,” in Proc. IEEE, vol. 57, no. 6, pp. 1195–1196, June 1969.
[35] Y. Ayasli, R. L. Mozzi, J. L. Vorhaus, L. D. Reynolds, and R. A. Pucel, “A monolithic GaAs 1-13 GHz traveling-wave amplifier,” IEEE Trans. Microw. Theory Tech., vol. 30, no. 7, pp. 976–981, July 1982.
[36] J. B. Beyer, S. N. Prasad, R. C. Becker, J. E. Nordman, and G. K. Hohenwarter, “MESFET Distributed Amplifier Design Guidelines,” IEEE Trans. Microw. Theory Tech., vol. 32, no. 3, pp. 268–275, Mar. 1984.
[37] R. Svitek, and S. Raman, “5–6 GHz SiGe active I/Q subharmonic mixers with power supply noise effect characterization,” IEEE Microw. Wireless Compon. Lett., vol. 14, no. 7, pp. 319–321, July 2004.
[38] J. Y. Su, C. Meng, and P. Y. Wu, “Q-Band pHEMT and mHEMT subharmonic Gilbert upconversion mixers,” IEEE Microw. Wireless Compon. Lett., vol. 19, no. 6, pp. 392–394, June 2009.
[39] Y. Sun and C. J. Scheytt, “A 122 GHz sub-harmonic mixer with a modified APDP topology for IC integration,” IEEE Microw. Wireless Compon. Lett., vol. 21, no.12, pp. 679–681, Dec. 2011.
[40] O. Habibpour, J. Vukusic, and J. Stake, “A 30-GHz integrated subharmonic mixer based on a multichannel graphene FET,” IEEE Trans. Microw. Theory Tech., vol. 61, no. 2, pp. 841–847, Feb. 2013.