A 23-dBm 60-GHz Distributed Active Transformer in a Silicon Process Technology

In this paper, a distributed active transformer for the operation in the millimeter-wave frequency range is presented. The transformer utilizes stacked coupled wires as opposed to slab inductors to achieve a high coupling factor of k_f=0.8 at 60 GHz. Scalable and compact equivalent-circuit models are used for the transformer design without the need for full-wave electromagnetic simulations. To demonstrate the feasibility of the millimeter-wave transformer, a 200-mW (23 dBm) 60-GHz power amplifier has been implemented in a standard 130-nm SiGe process technology, which, to date, is the highest reported output power in an SiGe process technology at millimeter-wave frequencies. The size of the output transformer is only 160times160 mum² and demonstrates the feasibility of efficient power combining and impedance transformation at millimeter-wave frequencies. The two-stage amplifier has 13 dB of compressed gain and achieves a power-added efficiency of 6.4% while combining the power of eight cascode amplifiers into a differential 100-Omega load. The amplifier supply voltage is 4 V with a quiescent current consumption of 300 mA     

Design of InP DHBT power amplifiers at millimeter-wave frequencies using interstage matched cascode technique

In this paper, the design of InP DHBT based millimeter-wave(mm-wave) power amplifiers(PAs) using an interstage matched cascode technique is presented. The output power of a traditional cascode is limited by the early saturation of the common-base(CB) device. The interstage matched cascode can be employed to improve the power handling ability through optimizing the input impedance of the CB device. The minimized power mismatch between the CB and the common-emitter(CE) devices results in an improved saturated output power. To demonstrate the technique for power amplifier designs at mm-wave frequencies, a single-branch cascode based PA using single-finger devices and a two-way combined based PA using three-finger devices are fabricated. The single-branch design shows a measured power gain of 9.2 dB and a saturated output power of 12.3 dBm at 67.2 GHz and the two-way combined design shows a power gain of 9.5 dB with a saturated output power of 18.6 dBm at 72.6 GHz.     

Design of high-power, high-efficiency 60-GHz MMICs using animproved nonlinear PHEMT model

This work describes the design and nonlinear modeling of two V-band monolithic microwave integrated circuit (MMIC) power amplifiers using a nonlinear high electron mobility transistor (HEMT) model developed specifically for very short gate length pseudomorphic HEMTs (PHEMTs). Both circuits advance the state-of-the-art of V-band power MMIC performance. The first, a single-ended design, produced 293 mW of output power with a record 26% power-added efficiency (PAE) and 9.9 dB of power gain at 62.5 GHz when measured on-wafer. The second MMIC, a balanced design with on-chip input and output Lange couplers for power combining, generated a record 564 mW of output power (27.5 dBm) with 21% PAE and 9.8 dB power gain. The MMIC's are passivated, thinned to 2 mils, and down-biased to 4.5 V for high reliability space applications. These excellent first-pass MMIC results are attributed to the use of an optimized 0.1-/μm PHEMT cell structure and a design based on millimeter-wave on-wafer device characterization, together with a new and very accurate large signal analytical FET model developed for 0.1-/μm PHEMTs     

High Power SiGe X-Band (8～10GHz) Heterojunction Bipolar Transistors and Amplifiers

Limited by increased parasitics and thermal effects as device size increases, current commercial SiGe power HBTs are difficult to operate at X-band (8～ 12GHz) frequencies with adequate power added efficiencies at high power levels. We find that, by changing the heterostructure and doping profile of SiGe HBTs, their power gain can be significantly improved without resorting to substantial lateral scaling. Furthermore, employing a common-base configuration with a proper doping profile instead of a common-emitter configuration improves the power gain characteristics of SiGe HBTs, thus permitting these devices to be efficiently operated at X-band frequencies. In this paper,we report the results of SiGe power HBTs and MMIC power amplifiers operating at 8～10GHz. At 10GHz,a 22.5dBm (178mW) RF output power with a concurrent gain of 7.32dB is measured at the peak power-added efficiency of 20.0%, and a maximum RF output power of 24.0dBm (250mW) is achieved from a 20 emitter finger SiGe power HBT. The demonstration of a single-stage X-band medium-power linear MMIC power amplifier is also realized at 8GHz. Employing a 10-emitter finger SiGe HBT and on-chip input and output matching passive components, a linear gain of 9.7dB,a maximum output power of 23.4dBm,and peak power added efficiency of 16% are achieved from the power amplifier. The MMIC exhibits very low distortion with 3rd order intermodulation (IM) suppression C/I of -13dBc at an output power of 21.2dBm and over 20dBm 3rd order output intercept point (OIP3).     

High Power SiGe X-Band (8～10GHz) Heterojunction Bipolar Transistors and Amplifiers

Limited by increased parasitics and thermal effects as device size increases,current commercial SiGe power HBTs are difficult to operate at X-band (8～12GHz) frequencies with adequate power added efficiencies at high power levels.We find that,by changing the heterostructure and doping profile of SiGe HBTs,their power gain can be significantly improved without resorting to substantial lateral scaling.Furthermore,employing a common-base configuration with a proper doping profile instead of a common-emitter configuration improves the power gain characteristics of SiGe HBTs,thus permitting these devices to be efficiently operated at X-band frequencies.In this paper,we report the results of SiGe power HBTs and MMIC power amplifiers operating at 8～10GHz.At 10GHz,a 22.5dBm (178mW) RF output power with a concurrent gain of 7.32dB is measured at the peak power-added efficiency of 20.0%,and a maximum RF output power of 24.0dBm (250mW) is achieved from a 20 emitter finger SiGe power HBT.The demonstration of a single-stage X-band medium-power linear MMIC power amplifier is also realized at 8GHz.Employing a 10-emitter finger SiGe HBT and on-chip input and output matching passive components,a linear gain of 9.7dB,a maximum output power of 23.4dBm,and peak power added efficiency of 16% are achieved from the power amplifier.The MMIC exhibits very low distortion with 3rd order intermodulation (IM) suppression C/I of -13dBc at an output power of 21.2dBm and over 20dBm 3rd order output intercept point (OIP3).     

High Power SiGe X-Band (8～10GHz) Heterojunction Bipolar Transistors and Amplifiers

Limited by increased parasitics and thermal effects as device size increases, current commercial SiGe power HBTs are difficult to operate at X-band (8～ 12GHz) frequencies with adequate power added efficiencies at high power levels. We find that, by changing the heterostructure and doping profile of SiGe HBTs, their power gain can be significantly improved without resorting to substantial lateral scaling. Furthermore, employing a common-base configuration with a proper doping profile instead of a common-emitter configuration improves the power gain characteristics of SiGe HBTs, thus permitting these devices to be efficiently operated at X-band frequencies. In this paper,we report the results of SiGe power HBTs and MMIC power amplifiers operating at 8～10GHz. At 10GHz,a 22.5dBm (178mW) RF output power with a concurrent gain of 7.32dB is measured at the peak power-added efficiency of 20.0%, and a maximum RF output power of 24.0dBm (250mW) is achieved from a 20 emitter finger SiGe power HBT. The demonstration of a single-stage X-band medium-power linear MMIC power amplifier is also realized at 8GHz. Employing a 10-emitter finger SiGe HBT and on-chip input and output matching passive components, a linear gain of 9.7dB,a maximum output power of 23.4dBm,and peak power added efficiency of 16% are achieved from the power amplifier. The MMIC exhibits very low distortion with 3rd order intermodulation (IM) suppression C/I of -13dBc at an output power of 21.2dBm and over 20dBm 3rd order output intercept point (OIP3).     

一种超宽带毫米波倍频器设计

叙述了一种超宽带毫米波倍频器的设计,该倍频器由有源差分balun级、对管倍频级和分布式功率放大级三个部分组成。在30—50GHz输出频率范围内,倍频器具有5dB的变频增益,输出功率大于13dBm,基波抑制大于15dB。     

Millimeter-wave CMOS design

This paper describes the design and modeling of CMOS transistors, integrated passives, and circuit blocks at millimeter-wave (mm-wave) frequencies. The effects of parasitics on the high-frequency performance of 130-nm CMOS transistors are investigated, and a peak f/sub max/ of 135 GHz has been achieved with optimal device layout. The inductive quality factor (Q/sub L/) is proposed as a more representative metric for transmission lines, and for a standard CMOS back-end process, coplanar waveguide (CPW) lines are determined to possess a higher Q/sub L/ than microstrip lines. Techniques for accurate modeling of active and passive components at mm-wave frequencies are presented. The proposed methodology was used to design two wideband mm-wave CMOS amplifiers operating at 40 GHz and 60 GHz. The 40-GHz amplifier achieves a peak |S/sub 21/| = 19 dB, output P/sub 1dB/ = -0.9 dBm, IIP3 = -7.4 dBm, and consumes 24 mA from a 1.5-V supply. The 60-GHz amplifier achieves a peak |S/sub 21/| = 12 dB, output P/sub 1dB/ = +2.0 dBm, NF = 8.8 dB, and consumes 36 mA from a 1.5-V supply. The amplifiers were fabricated in a standard 130-nm 6-metal layer bulk-CMOS process, demonstrating that complex mm-wave circuits are possible in today's mainstream CMOS technologies.     

A gallium-nitride push-pull microwave power amplifier

A highly efficient linear, broad-band AlGaN-GaN high electron-mobility transistor (HEMT) push-pull microwave power amplifier has been achieved using discrete devices. Instrumental was a low-loss planar three-coupled-line balun with integrated biasing. Using two 1.5-mm GaN HEMTs, a push-pull amplifier yielded 42% power-added efficiency with 28.5-dBm input power at 5.2 GHz, and a 3-dB bandwidth of 4-8.5 GHz was achieved with class-B bias. The output power at 3-dB gain compression was 36 dBm under continuous-wave operation. Along with the high efficiency, good linearity was obtained compared to single-ended operation. The second harmonic content of the amplifier was more than 30 dB down over the 4-8.5-GHz band, and a two-tone excitation measurement gave an input third-order intercept point of 31.5 dBm at 8 GHz. These experimental results and an analysis of the periodic load presented by the output balun suggest the plausibility of broad-band push-pull operation for microwave systems with frequency diversity.     

Watt-level Ka- and Q-band MMIC power amplifiers operating at lowvoltages

Ka- and Q-band watt-level monolithic power amplifiers (PAs) operating at a low drain bias of 3.6 V are presented in this paper. Design considerations for low-voltage operation have been carefully studied, with an emphasis on the effect of device models. The deficiency of conventional table-based models for low-voltage operation is identified. A new nonlinear device model, which combines the advantages of conventional analytical models and table-based models, has been developed to circumvent the numerical problems and, thus, to predict optimum load impedance accurately. The model was verified with load-pull measurements at 39 GHz. To implement a low-voltage 1-W monolithic-microwave integrated-circuit amplifier, careful circuit design has been performed using this model. A Q-band two-stage amplifier showed 1-W output power with a high power gain of 15 dB at 3.6-V drain bias. The peak power-added efficiency (PAE) was 28.5% and 1-dB compression power (P_{1 dB}) was 29.7 dBm. A Ka-band two-stage amplifier showed a P_{1 dB} of 30 dBm with 24.5-dB associated gain and 32.5% PAE. Under very low dc power conditions (P_dc<2 W, V_ds=3.4 V), the amplifiers showed 29-dBm output power and PAE close to 36%, demonstrating ultimate low-power operation capability. To the best of our knowledge, this is the first demonstration of watt-level PA's under 3.6-V operation at 26 and 40 GHz. Compared with the published data, this work also represents state-of-the-art performance in terms of power gain, efficiency, and chip size     

Integrated complementary HBT microwave push-pull and Darlingtonamplifiers with p-n-p active loads

The authors report the microwave results of complementary heterojunction bipolar transistor (HBT) amplifiers that integrate both n-p-n and p-n-p devices on the same chip using selective molecular beam epitaxy (MBE). An HBT wideband amplifier utilizing the Darlington configuration and implementing a p-n-p active load has a gain of 7.5 dB and a bandwidth from DC to 2.5 GHz. A complementary push-pull amplifier has a saturated output power of 7.5 dBm at 2.5 GHz     

Efficient EM Simulation of GCPW Structures Applied to a 200-GHz mHEMT Power Amplifier MMIC

The behaviour of grounded coplanar waveguide (GCPW) structures in the upper millimeter-wave range is analyzed by using full-wave electromagnetic (EM) simulations. A methodological approach to develop reliable and time-efficient simulations is proposed by investigating the impact of different simplifications in the EM modelling and simulation conditions. After experimental validation with measurements on test structures, this approach has been used to model the most critical passive structures involved in the layout of a state-of-the-art 200-GHz power amplifier based on metamorphic high electron mobility transistors (mHEMTs). This millimeter-wave monolithic integrated circuit (MMIC) has demonstrated a measured output power of 8.7 dBm for an input power of 0 dBm at 200 GHz. The measured output power density and power-added efficiency (PAE) are 46.3 mW/mm and 4.5 %, respectively. The peak measured small-signal gain is 12.7 dB (obtained at 196 GHz). A good agreement has been obtained between measurements and simulation results.     

Design Considerations for 60 GHz Transformer-Coupled CMOS Power Amplifiers

This work discusses the design methodologies for efficient power generation at mm-wave frequencies in CMOS. Passive elements play an important role in PA design, as they determine both the output power and power gain of the circuit. In this work, we have developed a methodology for design of transformer-coupled power amplifiers. A distributed model of on-chip transformers has been developed that can predict the performance up to very high frequencies, is length scalable and uses only a few parameters , compared to a complete lumped model. Using the model, a two-stage transformer-coupled PA has been designed in 90 nm CMOS. The prototype has one of the highest output powers reported for a 60 GHz CMOS PA. A three-stage improved design with higher gain and efficiency is reported, stressing the importance of driver stage design at these frequencies. The PA has been integrated into a complete transmitter and tested with 10 Gb/s QPSK modulated data.     

Fully Integrated CMOS Power Amplifier With Efficiency Enhancement at Power Back-Off

This paper presents a new approach for power amplifier design using deep submicron CMOS technologies. A transformer based voltage combiner is proposed to combine power generated from several low-voltage CMOS amplifiers. Unlike other voltage combining transformers, the architecture presented in this paper provides greater flexibility to access and control the individual amplifiers in a voltage combined amplifier. In this work, this voltage combining transformer has been utilized to control output power and improve average efficiency at power back-off. This technique does not degrade instantaneous efficiency at peak power and maintains voltage gain with power back-off. A 1.2 V, 2.4 GHz fully integrated CMOS power amplifier prototype was implemented with thin-oxide transistors in a 0.13 mum RF-CMOS process to demonstrate the concept. Neither off-chip components nor bondwires are used for output matching. The power amplifier transmits 24 dBm power with 25% drain efficiency at 1 dB compression point. When driven into saturation, it transmits 27 dBm peak power with 32% drain efficiency. At power back-off, efficiency is greatly improved in the prototype which employs average efficiency enhancement circuitry.     

基于40 nm CMOS工艺的高效率功率放大器设计

针对硅基毫米波功率放大器存在的饱和输出功率较低、增益不足和效率不高的问题,基于TSMC 40nm CMOS工艺,设计了一款工作在28GHz的高效率和高增益连续F类功率放大器。提出的功率放大器由驱动级和功率级组成。针对功率级设计了一款基于变压器的谐波控制网络来实现功率合成和谐波控制,有效地提高了功率放大器的饱和输出功率和功率附加效率。采用PMOS管电容抵消功率级的栅源电容,进一步提高线性度和增益。电路后仿真结果表明,设计的功率放大器在饱和输出功率为20.5dBm处的峰值功率附加效率54%,1dB压缩点为19dBm,功率增益为27dB,在24GHz~32GHz频率处的功率附加效率大于40%。     

Push-pull circuits using n-p-n and p-n-p InP-based HBT's for poweramplification

P-n-p heterojunction bipolar transistors (HBTs) have been combined with n-p-n HBTs in a push-pull amplifier in order to obtain improved linearity characteristics. Simulations of common-collector push-pull amplifiers demonstrate an improvement of 14 dB in second harmonic content at the onset of power saturation under class-B operation. Further improvement of 14 dB in the third harmonic content is shown by moving to class-AB operation at an expense of 4% decreased efficiency. A common-emitter push-pull amplifier was fabricated using both n-p-n and p-n-p HBTs with external matching and couplers. Testing of the circuit under class-AB conditions showed better third-order intermodulation (by ~9 dBc) and smaller second harmonic content (by ~11 dBc) compared with n-p-n HBTs alone. While the second harmonics were shown to combine destructively in the push-pull amplifier, total cancellation of the second harmonic was prevented by the wide difference in linearity characteristics of the n-p-n and p-n-p HBTs. In addition, the circuit produced over 2 dBm more output power than the n-p n HBT alone at 1 dB of gain compression     

Design of 20-44 GHz broadband doubler MMIC

This paper presents the design and performance of a broadband millimeter-wave frequency doubler MMIC using active 0.15 μm GaAs PHEMT and operating at output frequencies from 20 to 44 GHz. This chip is composed of a single ended-into differential-out active Balun, balanced FETs in push-push configuration, and a distributed amplifier. The MMIC doubler exhibits more than 4 dB conversion gain with 12 dBm of output power, and the fundamental frequency suppression is typically -20 dBc up to 44 GHz. The MMIC works at VDD = 3.5 V, VSS = -3.5 V, Id = 200 mA and the chip size is 1.5 ×1.8 mm2.     

A 44 GHz HEMT amplifier

A 44-GHz amplifier using 0.25-μm gate length and double-heterojunction structure HEMT devices is described. Higher gain and power performance have been obtained from the amplifier using this device at millimeter-wave frequencies. A spot gain of 9.4 dB and a 1-dB gain compression point of +7.5 dBm has been achieved at 43.5 GHz.     

A 4-W X-band compact coplanar high-power amplifier MMIC with 18-dB gain and 25% PAE

The performance of a compact coplanar microwave monolithic integrated circuit (MMIC) amplifier with high output power in the X-band is presented. Based on our 0.3-/spl mu/m gate-length GaAs power pseudomorphic high electron mobility transistor (PHEMT) process on 4-in wafer, this two-stage amplifier, having a chip size of 16 mm/sup 2/, averages 4-W continuous-wave (CW) and 25% mean power-added efficiency (PAE) in the X-band, with more than 18-dB linear gain. Peak output powers of P/sub -1dB/=36.3dBm (4.3 W) and P/sub sat/ of 36.9 dBm (4.9 W) at 10 GHz with a PAE of 50% were also measured. Compared to previously reported X-band coplanar high-power amplifiers, this represents a chip size reduction of 20%, comparable to the size of compact state-of-the-art microstrip power amplifiers.     

Millimeter-Wave Integrated Circuits in 65-nm CMOS

We present the design and measurement results of millimeter-wave integrated circuits implemented in 65-nm baseline CMOS. Both active and passive test structures were measured. In addition, we present the design of an on-chip spiral balun and the transition from CPW to the balun and report transistor noise parameter measurement results at V-band. Finally, the design and measurement results of two amplifiers and a balanced resistive mixer are presented. The 40-GHz amplifier exhibits 14.3 dB of gain and the 1-dB output compression point is at $+$6-dBm power level using a 1.2 V supply with a compact chip area of 0.286 ${hbox{mm}}^{2}$. The 60-GHz amplifier achieves a measured noise figure of 5.6 dB at 60 GHz. The AM/AM and AM/PM results show a saturated output power of $+$7 dBm using a 1.2 V supply. In downconversion, the balanced resistive mixer achieves 12.5 dB of conversion loss and $+$5 dBm of 1-dB input compression point. In upconversion, the measured conversion loss was 13.5 dB with $-$19 dBm of 1-dB output compression point.