739 A 45-GHz Quadrature Voltage Controlled Oscillator with a Reflection-Type IQ Modulator in.3-pm CMOS Technology Hong-Yeh Chang, Yi-Hsien Cho, Ming-Fong Lei, Chin-Shen Lin, Tian-Wei Huang, and Huei Wang Department of Electrical Engineering and Graduate Institute of Communication Engineering, National Taiwan University, Taipei, 6, Taiwan, R.O.C. Abstract - In this paper, a 45-GHz quadrature voltage controlled oscillator (QVCO) with a reflection-type IQ modulator in.3-ptm CMOS technology is presented. An innovative configuration for the QVCO with an IQ modulator is proposed, in which the amplitude and phase errors of QVCO can be accurately evaluated in millimeter-wave (MMW) frequency range. The phase noise of QVCO is better than -99 dbc/hz at carrier offset frequency of MHz, and the tuning frequency is from 44.8 to 45.8 GHz. For single-sideband up-converter application, this circuit demonstrates a sideband suppression of better than -36 dbc, and a LO suppression of better than -27 dbc. Based on the calculation of the sideband suppression contours, the amplitude and phase errors of the QVCO are within.3 db and 2. To the best of authors' knowledge, this is the first attempt to integrate a QVCO with a reflection-type IQ modulator in MMW regime for the characterization of amplitude and phase errors in a QVCO and the direct upconversion applications. Index Terms - CMOS, Direct conversion, Modulator, QVCO. I. INTRODUCTION QVCO is an essential component for the direct conversion transceiver due to the requirement of quadrature LO signals. To date, there are several methods for generating quadrature signals, such as resistance-capacitance capacitance-resistance (RC-CR) phase shifter, 9 coupler (e. g., Lange, branch-line, and broadside couplers), frequency divider based on D-type flip flop, even-stage ring oscillator, and two parallel- or series-coupled cross-coupled inductance-capacitance (LC)loaded oscillator []. LC-loaded QVCOs using CMOS technology were reported in []-[5], and QVCOs using SiGe technology were in [6]-[8]. Most of them are below 3 GHz, except for the SiGe-based QVCO in [8] is up to 32 GHz with a chip size of.7 x.2 mm2, and a DC supply voltage of 5 V. To verify the amplitude and phase errors of the QVCO, the circuits usually include two mixers (e. g., Gilbert cell or resistive ring mixers) and configured as an IQ direct conversion converter []-[3], [6], [8]; the errors may be extracted by measuring the sideband suppression. The amplitude and phase errors also can be obtained by measuring the time domain signals with a sampling scope [7], but the measured errors introduced by cables, connectors and probes are difficult to remove. Recently, we reported a modified reflection-type IQ modulator in [9], which used a broadside coupler and two transformers to generate the quadrature LO signals for the -783-9542-5/6/$2. C26 IEEE orthogonal modulation applications. In this paper, we combined a parallel-coupled QVCO and a reflection-type IQ modulator in a single chip. The advantage of this innovative configuration is easy evaluation of the amplitude and phase errors of the QVCO in MMW, since the modulator can perform the functions of switch and amplitude-phase modulation. When the modulator is operated as a switch, the amplitude of the four paths output in QVCO can be measured individually, and then the amplitude error of the QVCO is obtained accurately due to the perfectly symmetric structure. In order to evaluate the phase error of the QVCO, the modulator also can be operated as an image suppression upconverter, and the sideband suppression is measured to extract the phase error by calculating the sideband suppression contours. In addition, we can easily implement a MMW direct conversion up-converter by using this innovative configuration due to its good modulation quality and simple structure. The performance summaries of previously reported QVCOs and this work are summarized in Table I. This work exhibits low amplitude/phase errors, low phase noise, good sideband/lo suppressions, and the oscillator is also the highest operation frequency among all the reported CMOS or SiGe QVCOs II. CIRCUIT DESIGN The circuit design is realized in TSMC commercial standard bulk.3-ptm P8M CMOS process. The NMOS devices exhibit a unit current gain frequency (ft) of higher than 9 GHz and a maximum oscillation frequency (fmax) of higher than GHz. To reduce the chip area and substrate loss, the circuit is implemented utilizing thin-film microstrip line structure; the bottom metal (metal ) is used as the ground plane, and the top metals (metal 7 or 8) as the signal line. The schematic of the 45-GHz QVCO with a reflection-type IQ modulator is shown in Fig.. The QVCO consists of two cross-coupled LC-loaded oscillators and four parallel-coupled transistors. Two MOS capacitors are parallel to the LC tank to expand the frequency tuning range of the QVCO. There are four coupling signals between two cross-coupled oscillators, and the cross junctions of the coupling signals cannot be omitted from the layout. The cross junctions need to be carefully designed because the amplitude and phase errors of the QVCO would be affected by the coupling
74 Ref. Process TABLE I. COMPARISON OF PREVIOUSLY REPORTED QVCOS AND THIS WORK Frequency Phase Noise Amp. and Phase Sideband LO Core Power (GHz) [] [2] [3].35,um CMOS.9-2.2.8,um CMOS 2.34-2.55 5.3.25,um CMOS 8 [4]*.8,um CMOS [5]*.8,um CMOS - SiGe 4.5-6 [6].4,um SiGe 24-28 [7]* [8].25,um SiGe 3.5-32.6 This Work.3 tm CMOS 44.8-45.8 * Only QVCO (dbc/hz) d* MHz -2.3-2 -86 d@ khz -7-2 -2.5-84.2-97 -98.9 Errors.5 db.8.2 db.5.4 db 2.45.7 db /4.5.5 db/ 5. db /.6.27 db.8 Suppression Suppression Consumption (dbc) (dbc) -33.4-22.4-42 -48-28 - -45 <-36 <-27 --- (mw) FOM (db) - 8-69 -75.6 25.8 7 29 4 4-8 -88-7 -52-65.6-76. variable resistors controlled by the gate bias. The design methodology of the reflection-type modulator was presented in [9]. From the operation principle and analysis of the modified reflection-type modulator [9], we can observe that the amplitude and phase imbalances (or sideband suppression) of the IQ modulator are dominated by the quadrature LO signals, and the amplitude and phase errors of the couplers only affect insertion loss and phase delay. Based on the characteristics of the modified reflection-type modulator, we can easily combine the QVCO and the IQ modulator circuits in a single chip and realize a direct conversion up-converter in MMW. To extract the amplitude and phase errors of the QVCO, the circuit is operated as image-suppression directconversion up-converter, and then the sideband suppression can be measured to extract the amplitude and phase errors from the sideband suppression contours. To evaluate the amplitude error of the QVCO, the modulators are operated as a single-port-single-throw (SPST) switch. One of the modulator (the port to be measured) is turned on, the other three modulators are off, and the isolation of off-state modulator is better than 4 db. Similarly, we assume that the insertion losses and phase delays of four modulators are the same. The phase error of the QVCO can also be measured by a sampling scope. The phase error can be extracted from the measured time domain signals of four paths when the modulators are turned on one by one. Using this method, the amplitude and phase errors due to cable, probe, and connectors will all be eliminated, since the quadrature signals go through the same paths to the scope. All of the passive components, such as LC tank, transmission lines, couplers, bypass, and dc-block capacitors, are simulated with a full-wave EM simulator []. In order to minimize the amplitude and phase errors, the circuit layout is designed as symmetric as possible. The chip photo of the complete 45-GHz QVCO with a reflection-type IQ is shown in Fig. 2 with a chip size of.85 x.6 mm2. capacitors at the junctions. In order to reduce the coupling capacitance, the cross junctions are implemented using metal and 8 with minimum line width. The line lengths of the four signals are also kept as symmetric as possible to ensure equal phase delay along all paths. The quadrature phase signals are individually amplified by a single stage buffer amplifier to decrease the load effect, and then the quadrature signals output to four reflection-type modulators. The inductors in the LC tank are realized using low impedance microstrip lines to enhance the Q factor of the LC tank due to the small parasitic resistance of the low impedance line. Fig.. Schematic of the 45-GHz QVCO with a reflection-type IQ modulator. The reflection-type modulator consists of a 9 broadside coupler and two cold-mode NMOS. The NMOSs are connected to the coupled and direct ports and performed as 2
74 when the modulators are operated as switches. Only the modulator in the measured path is turned on ( V), the other three are turned off (.5 V). The measurement results are plotted in Fig. 7 that shows an amplitude error of within db. The off-state output power is around -4 dbm when the four modulators are all turned off. TABLE II. BIAS CONDITIONS FOR THE PHASE-SHIFT OPERATION IP (V) State QN (V) IN (V) QP (V).5 OFF.5.5.5 Fig. 2. Chip photo of the complete 45-GHz QVCU with a reflection-type IQ modulator, the chip size is.85 x.6 mm2. III. EXPERIMENTAL RESULTS The measurements of the 45-GHz QVCO with a reflectiontype IQ modulator are performed via on-wafer probing. To evaluate the tuning frequency and output power of the QVCO, the four modulators are operated as phase shifters or switches. There are four phase-shift states and an off state in the operation, and the detail biases are listed in Table. Continuous phase-shift control can also be performed by adjusting the baseband input voltages based on the vector sum of the I-Q paths. The measured output frequency and power versus the tuning voltage from to 3 V is plotted in Fig. 3 for the QVCO. The tuning frequency is from 44.8 to 45. 8 GHz with an RF power of higher than -3 dbm at the output GSG pad. The measured phase noise versus offset carrier frequency is plotted in Fig. 4 for the QVCO, which features a phase noise of better than -99 dbc/hz at -MHz offset frequency. The total dc and core power consumptions are 9 and 4 mw, respectively, with a dc supply voltage of V. This QVCO exhibits an FOM [7] of - 76 db at 45 GHz. Sideband suppression measurement is used to evaluate the amplitude and phase errors of the QVCO. In the measurement setup, the baseband I-Q signals are generated by an Agilent E4438C arbitrary waveform generator, and the output spectrum is measured by an Agilent E4448A spectrum analyzer. The baseband signals are 5-MHz sinusoid continuous waveform with a dc level of.5 V, and the total baseband input power is about - dbm. The measured output spectrum of sideband suppression is plotted in Fig. 5 for the direct conversion up-converter, and the tuning voltage of the QVCO is V. The measured LO and sideband suppressions versus the tuning voltage from to 3 V is plotted in Fig. 6 which features a LO suppression of better than -26 dbc and a sideband suppression of better than -36 dbc. From the sideband suppression contours, the extracted amplitude and phase errors of the QVCO are within.3 db and 2, respectively. Furthermore, the amplitude error is also evaluated by measuring the four output powers of the QVCO ', 45.25 C4) a) - P4 a). 45...5..5 2. 2.5 3. -5 Control Voltage (V) Fig. 3. Measured output frequency and power versus the tuning voltage from to 3 V for the QVCO. Carrier Power 9.57 dbm Atten. db Re -3).OOdBc/Hz. Mkr 999.638 khz -98.9 dbc/hz db/ Fig. 4. khz Frequency utse Measured phase noise for the QVCO. W [MHz IV. CONCLUSION An innovative configuration of a QVCO with an IQ modulator is proposed in this paper for MMW applications. The characterization of the amplitude and phase errors for the QVCO is also successfully presented. The high frequency QVCOs can be easily evaluated by utilizing this method due to the perfect symmetric structure. It is especially useful for the MMW QVCOs since the MMW time domain 3
742 measurement is difficult to perform as well as the calibration for the measurement setup. A 45-GHz QVCO using.3-ptm standard commercial bulk CMOS process is demonstrated with low phase noise and good amplitude/phase balances. Also this circuit can be operated as a direct conversion upconverter with good sideband/lo suppressions for the potential MMW applications. Ref - Norm Log le db/ Hkrl.i3 MHz ACKNOWLEDGEMENT The work was supported in part by the National Science Council under Grant NSC 93-2752-E-2-2-PAE, and Grant NSC 93-229-E-2-24. The chip is fabricated by Taiwan Semiconductor Manufacturing Company (TSMC), Hsinchu, Taiwan, R.O.C., through Chip implementation Center (CIC), Hsinchu, Taiwan, R.O.C. REFERENCES [] Chung-Yu Wu, and Hong-Sing Kao, "A 2-V low-power CMOS direct-conversion quadrature modulator with integrated quadrature voltage-controlled oscillator and RF amplifier for GHz RF transmitter appllications," IEEE Trans. On Circuits and System-II: Analog and Digital Signal Process, vol. 49 Feb. 22, pp. 23-34. [2] Seong-Mo Moon, and et al, "Design of quadrature CMOS VCO using source degeneration resistor," 25 Radio Frequency Integrated Circuits Symposium Digest, Long Beach, USA, pp. 535-538. [3] Ting-Ping Liu, and Eric Westerwick, "5-GHz CMOS radio transceiver front-end chipset," IEEE Journal of Solid-State Circuits, vol. 35, no. 2, pp. 927-933, December 2. [4] Donghyun Baek, Taeksang Song, Euisik Yoon, and Songcheol Hong, "8-GHz CMOS quadrature VCO using transformer-based LC tank," IEEE Microwave and Wireless Components Letters, vol. 3, no., pp. 446-448, October 23. [5] Sangsoo Ko, and et al, "2 GHz Integrated CMOS frequency sources with a quadrature VCO using transformers," 24 Radio Frequency Integrated Circuits Symposium Digest, Dallas, USA, pp. 269-272. [6] Timothy M. Hancock, and Gabriel M. Rebeiz, "A novel superharmonic coupling topology for quadrature oscillator design at 6 GHz," 24 Radio Frequency Integrated Circuits Symposium Digest, Dallas, USA, pp. 285-288. [7] Sabine Hackl, Josef Bock, Gunter Ritzberger, Martin Wurzer, and Arpad L. Scholtz "A 28-GHz monolithic integrated quadrature oscillator in SiGe Bipolar Technology," IEEE Journal of Solid-State Circuits, vol. 38, no., pp. 35-37, January 23. [8] W. L. Chan, H. Veenstra, and J. R. Long, "A 32GHz quadrature LC-VCO in.25,um SiGe BiCMOS Technology," 25 International Solid-State Circuit Conference Digest, San Francisco, USA, pp. 538-539. [9] Hong-Yeh Chang, Pei-Si Wu, Tian-Wei Huang, Huei Wang, Chung-Long Chang, and John Chern, "Design and analysis of CMOS broadband compact high-linearity modulators for Gigabit microwave/millimeter-wave applications," IEEE Trans. on Microwave Theory and Tech, pp. 2-3, Jan. 26. [] Sonnet User's Manual, Release 9., Sonnet Software Inc., North Syracuse, NY, May, 23. LgRv wi St S3 F T f FTun Swp Center 45.772 2 GHz Span 5 MHz Fig. 5. Measured output spectrum of sideband suppression for the direct conversion up-converter with baseband frequency of 5 MHz, and the tuning voltage of the QVCO is V. C.) m.2 'A 'a) Q V:n -5-2 P -25 F -3 k -35 H -4-45 -5..5..5 2. 2.5 3. Control Voltage (V) Fig. 6. Measured LO and sideband suppressions versus the tuning voltage from to 3 V for the direct conversion transmitter. -, -2J -2-25 k -3, iv 4-35 -4-45 -5 -U * Sideband Suppression.* LO Suppression *U- IP IN QP v QN *- OFF -U..5..5 2. 2.5 3. Control Voltage (V) Fig. 7. Measured RF powers of four outputs versus the tuning voltage from to 3 V for the QVCO. 4
易迪拓培训 专注于微波 射频 天线设计人才的培养网址 :http://www.edatop.com 射频和天线设计培训课程推荐 易迪拓培训 (www.edatop.com) 由数名来自于研发第一线的资深工程师发起成立, 致力并专注于微波 射频 天线设计研发人才的培养 ; 我们于 26 年整合合并微波 EDA 网 (www.mweda.com), 现已发展成为国内最大的微波射频和天线设计人才培养基地, 成功推出多套微波射频以及天线设计经典培训课程和 ADS HFSS 等专业软件使用培训课程, 广受客户好评 ; 并先后与人民邮电出版社 电子工业出版社合作出版了多本专业图书, 帮助数万名工程师提升了专业技术能力 客户遍布中兴通讯 研通高频 埃威航电 国人通信等多家国内知名公司, 以及台湾工业技术研究院 永业科技 全一电子等多家台湾地区企业 易迪拓培训课程列表 :http://www.edatop.com/peixun/rfe/29.html 射频工程师养成培训课程套装该套装精选了射频专业基础培训课程 射频仿真设计培训课程和射频电路测量培训课程三个类别共 3 门视频培训课程和 3 本图书教材 ; 旨在引领学员全面学习一个射频工程师需要熟悉 理解和掌握的专业知识和研发设计能力 通过套装的学习, 能够让学员完全达到和胜任一个合格的射频工程师的要求 课程网址 :http://www.edatop.com/peixun/rfe/.html ADS 学习培训课程套装该套装是迄今国内最全面 最权威的 ADS 培训教程, 共包含 门 ADS 学习培训课程 课程是由具有多年 ADS 使用经验的微波射频与通信系统设计领域资深专家讲解, 并多结合设计实例, 由浅入深 详细而又全面地讲解了 ADS 在微波射频电路设计 通信系统设计和电磁仿真设计方面的内容 能让您在最短的时间内学会使用 ADS, 迅速提升个人技术能力, 把 ADS 真正应用到实际研发工作中去, 成为 ADS 设计专家... 课程网址 : http://www.edatop.com/peixun/ads/3.html HFSS 学习培训课程套装该套课程套装包含了本站全部 HFSS 培训课程, 是迄今国内最全面 最专业的 HFSS 培训教程套装, 可以帮助您从零开始, 全面深入学习 HFSS 的各项功能和在多个方面的工程应用 购买套装, 更可超值赠送 3 个月免费学习答疑, 随时解答您学习过程中遇到的棘手问题, 让您的 HFSS 学习更加轻松顺畅 课程网址 :http://www.edatop.com/peixun/hfss/.html `
易迪拓培训 专注于微波 射频 天线设计人才的培养网址 :http://www.edatop.com CST 学习培训课程套装该培训套装由易迪拓培训联合微波 EDA 网共同推出, 是最全面 系统 专业的 CST 微波工作室培训课程套装, 所有课程都由经验丰富的专家授课, 视频教学, 可以帮助您从零开始, 全面系统地学习 CST 微波工作的各项功能及其在微波射频 天线设计等领域的设计应用 且购买该套装, 还可超值赠送 3 个月免费学习答疑 课程网址 :http://www.edatop.com/peixun/cst/24.html HFSS 天线设计培训课程套装套装包含 6 门视频课程和 本图书, 课程从基础讲起, 内容由浅入深, 理论介绍和实际操作讲解相结合, 全面系统的讲解了 HFSS 天线设计的全过程 是国内最全面 最专业的 HFSS 天线设计课程, 可以帮助您快速学习掌握如何使用 HFSS 设计天线, 让天线设计不再难 课程网址 :http://www.edatop.com/peixun/hfss/22.html 3.56MHz NFC/RFID 线圈天线设计培训课程套装套装包含 4 门视频培训课程, 培训将 3.56MHz 线圈天线设计原理和仿真设计实践相结合, 全面系统地讲解了 3.56MHz 线圈天线的工作原理 设计方法 设计考量以及使用 HFSS 和 CST 仿真分析线圈天线的具体操作, 同时还介绍了 3.56MHz 线圈天线匹配电路的设计和调试 通过该套课程的学习, 可以帮助您快速学习掌握 3.56MHz 线圈天线及其匹配电路的原理 设计和调试 详情浏览 :http://www.edatop.com/peixun/antenna/6.html 我们的课程优势 : 成立于 24 年, 多年丰富的行业经验, 一直致力并专注于微波射频和天线设计工程师的培养, 更了解该行业对人才的要求 经验丰富的一线资深工程师讲授, 结合实际工程案例, 直观 实用 易学 联系我们 : 易迪拓培训官网 :http://www.edatop.com 微波 EDA 网 :http://www.mweda.com 官方淘宝店 :http://shop369289.taobao.com 专注于微波 射频 天线设计人才的培养易迪拓培训官方网址 :http://www.edatop.com 淘宝网店 :http://shop369289.taobao.com