Monolithic Microwave Integrated Circuit Power Amplifier Research Articles

A High-Efficiency Inverse Class-F GaN MMIC Power Amplifier With Compact Output Matching Network

This brief presents a high-efficiency inverse Class-F (Class-F-1) monolithic microwave integrated circuit (MMIC) power amplifier (PA) fabricated with 0.25-lm GaN-on-Si technology. The design is based on a compact output matching network (COMN), which consists of a harmonic control circuit (HCC), an L-section matching circuit and a bias line. In order to reduce the circuit area that make it suitable for monolithic integration, the HCC uses only three transmission lines to achieve the second and third harmonic control. In addition, the conventional quarter-wave bias line is replaced with a shorter, proper one. The proposed COMN simplifies the matching network while realizing Class-F-1 operation, which improves efficiency, output power and reduce chip size. The maximum power added efficiency of 64.5% is achieved at 3.0 GHz, with an output power of 38.4 dBm and a power gain of 10.3 dB.

Temperature behavior modeling based on resilient BPNN for a GaAs pHEMT high gain MMIC PA

AbstractAs the key component of transceiver, power amplifier (PA) plays an extremely important role in wireless communication system. In order to accurately characterize the performance variation of PA at any temperature, the temperature behavior of a gallium arsenide (GaAs) pseudomorphic high electron mobility transistor (pHEMT) high gain monolithic microwave integrated circuit (MMIC) PA is modeled in this paper. In this modeling, the resilient back propagation neural network (BPNN) is utilized to do the temperature behavior modeling for this PA. The investigation shows that the minimum mean square error (MSE) of the prediction results is 4.9607 × 10−4, which implies that it is feasible to use this modeling method to characterize the temperature behavior of PA. This modeling not only theoretically overcomes the problem of slow convergence speed of BPNN, but also solves the limitation of experimental devices and time setting. It will provide a more convenient guidance for test engineers.

60 GHz 대역 28 dBm 출력전력을 갖는 GaAs 증가형 pHEMT 전력증폭기 MMIC 설계

A 60 GHz power amplifier (PA) monolithic microwave integrated circuit (MMIC) with +28 dBm output power is designed in an enhancement-mode 0.15 μm GaAs pseudomorphic high-electron-mobility transistor (pHEMT) technology. A two-stage topology and a four-way power combining technique are adopted to achieve a high power gain, high output power, and high linearity. Transistor-level circuit and layout designs are developed, and the circuit performances are verified through three-dimensional electromagnetic simulations. The designed PA MMIC exhibits a saturated output power of +28.4 dBm, output-referred 1-dB gain compression point of +28 dBm, power gain of +8.1 dB, and power added efficiency of 29.3 %. S-parameter simulations show that the small-signal gain is +8.1 dB, and the operating bandwidth is between 55.7 and 63.1 GHz, with a fractional bandwidth of 12.3 %. The supply voltages are 4 V for the drain and 0.6 V for the gate. The positive-only supply voltages resulting from the enhancement-mode pHEMT simplify the supply voltage network compared with the conventional depletion-mode pHEMT design. The layout die size of the PA MMIC is 1.99×1.62 mm2, and the power density performance of 214 mW/mm2 is satisfactory.

Design of X/Ku Dual-Wideband GaN Power Amplifier MMIC Based on Coupled Multiresonator Matching Networks

This brief presents an X/Ku concurrent dual-wideband power amplifier (PA) monolithic microwave integrated circuit (MMIC) fabricated with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.25{\mu }\text{m}$ </tex-math></inline-formula> GaN-on-SiC technology. The input matching network (IMN) and output matching network (OMN) of the proposed PA are designed based on electric and magnetic coupled symmetric multi-resonator matching networks (MRMNs) respectively to obtain four reflection zeros. Through symmetrical network analysis method, the four reflection zeros of the matching network are equally divided into two sub frequency bands and an optimal dual-wideband matching performance is realized. The proposed PA obtains average saturated output power of 36.9dBm and 35.9dBm in 9GHz–10GHz and 13.5GHz–16GHz. The measured average power-added efficiency (PAE) are 34.8% and 32.6% in 9GHz–10GHz and 13.5GHz–16GHz.

A Millimeter-Wave GaN MMIC Front End Module with 5G NR Performance Verification

This paper proposes a millimeter-wave (mmWave) 5G front end module (FEM) based on multiple gallium nitride (GaN) monolithic microwave integrated circuits (MMICs) with 5G new radio (NR) performance verification. The proposed structure is configured by a wide band GaN single-pole double-throw (SPDT) switch MMIC, a GaN low-noise amplifier (LNA) MMIC, and a GaN power amplifier (PA) MMIC with the target operation band from 26.5 GHz to 29.5 GHz. The LNA and PA MMICs are designed with 150 nm GaN/SiC technology, and the SPDT MMIC is designed with 100 nm GaN/Si. The LNA MMIC shows the measured noise figure less than or equal to 2.52 dB within the operation band. The PA MMIC is based on a two-stage configuration and shows about 35 dBm measured saturated power with power-added efficiency better than 34% within the operation band. Also, the SPDT MMIC is based on an artificial transmission line configuration for wideband performance and shows that the measured insertion loss is less than 1.6 dB, and the measured isolation is higher than 25 dB within the operation band. Furthermore, all MMICs are integrated within a single carrier as an FEM and successfully verified by 5G NR test signals.

A 7–13 GHz 10 W High-Efficiency MMIC Power Amplifier in 0.25 µm GaN HEMT Process

With the increase in applications of the millimeter wave spectrum for phased array radar systems, mobile 7–13 communication systems, and satellite systems, the demand for a wideband, high-efficiency, high-power monolithic microwave integrated circuit (MMIC) power amplifier (PA) is increasing. In this paper, a 7–13 GHz 10 W high-efficiency MMIC PA is designed. This amplifier consists of a two-stage circuit structure with two high electron mobility transistor (HEMT) cells for the driver stage and four HEMT cells for the power stage. To ensure high efficiency and a certain output power (Pout), both the driver–stage and power–stage transistors use a deep Class–AB bias. At the same time, in order to further improve the efficiency, low-loss and second–harmonic tuning techniques are used in the output and inter-stage matching networks, respectively. Finally, the electromagnetic simulation results show that within a frequency of 7–13 GHz, the amplifier achieves an average saturated continuous wave (CW) Pout of 40 dBm, a small signal gain of 14.5–15.5 dB, a power-added efficiency (PAE) of 30–46%, and the input and output return loss are better than 5 dB and 8 dB, respectively.

High-Performance RF Power Amplifier Module Using Optimum Chip-Level Packaging Structure

This article presents a high-performance radio frequency (RF) power amplifier (PA) module for which an optimum chip-level packaging structure is proposed to reduce the operating temperature of the RF PA monolithic microwave integrated circuit (MMIC). Because the output power ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">out</sub> ) and the efficiency of an RF PA module are strongly affected by the thermal characteristics of the PA MMIC, various types of heat spreader materials and thermal interface materials have been examined to implement the PA chip-level packaging structure, and the optimum combination is proposed for a performance enhancement of the PA module in this article. In addition, the optimum form-factor of the heat spreader was suggested based on a thermal simulation. To verify the proposed PA chip-level packaging structure, a 10 W 6–18 GHz RF PA MMIC using a commercial 0.25- <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">μ</i> m gallium nitride high electron mobility transistor process was designed and implemented for radar applications. The operating temperature of the PA MMIC on the proposed chip-level packaging structure shows a dramatic reduction of 24.8 °C, and accordingly, the average <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">out</sub> and average power-added efficiency are enhanced by up to 9.2% and 2.8%, respectively, when compared with a PA module using the conventional chip-level packaging structure.

Low-Loss Heterogeneous Integrations With High Output Power Radar Applications at W-Band

This study presents a design of a 94-GHz high-performance and highly compact frequency-modulated continuous-wave radar sensor. In this sensor, an <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$X$ </tex-math></inline-formula> -band CMOS-based all-digital phase-locked loop chip, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$W$ </tex-math></inline-formula> -band SiGe-based transceiver monolithic microwave integrated circuit (MMIC), and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$W$ </tex-math></inline-formula> -band GaN-based MMIC power amplifier (PA) are heterogeneously integrated (HI). Each part of the 130-nm bipolar complementary metal-oxide-semiconductor (BiCMOS) SiGe-based transceiver MMIC is designed to include a low-noise amplifier, PA, octupler, mixer, and lange coupler. The fabrication process of our in-house silicon-based MEMS photosensitive composite film is developed to provide very high-density integration and very low insertion loss of interconnections between chips. The HI front end of the radar sensor is measured on-wafer with a high output power of 22 dBm. Moreover, a low double-sideband noise figure (NF) of 10.2 dB is obtained. Bonding–substrate integrated waveguide (SIW)–WG transitions between the heterogeneously integrated front end and the antenna are specially designed and verified. A 2.3-dB degradation is observed, where 19.7 dBm is measured at the transmitter WG WR-10-flange. Thus, the sensor offers a 55-dB dynamic range at a 2-m position with an expectation of a long-distance target-detection range. The radar sensor has an 11.7-cm range resolution and is only <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$60\times 40\times $ </tex-math></inline-formula> 8 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> in size, with a weight of only 78 g.

Performance Degradation Investigation for a GaAs PHEMT High Gain MMIC PA Taking into Account the Temperature

In order to comprehensively grasp the performance changes for the monolithic microwave integrated circuit (MMIC), this paper proposes that the complete temperature reliability tests for a 2.4–4.4 GHz gallium arsenide (GaAs) pseudomorphic high electron mobility transistor (pHEMT) high gain power amplifier (PA) should be investigated. The performance for this MMIC PA at different temperatures has been presented effectively. The results show that the direct current (DC) characteristics, small-signal gain (S21), and radio frequency (RF) output characteristics for this MMIC PA decrease and the output third-order intersection point (OIP3) increases with the rising temperature. The main factor influencing the performance is analyzed in detail. For further applications of this MMIC PA, several measures can be utilized to remedy the performance degradation. This paper can provide significant engineer guidance for the reliability design of RF microwave circuits.

Design of 70% PAE Class‐F 1.2–1.4 GHz 10 W GaN power amplifier MMIC

AbstractThis letter presents a novel design of a Class‐F monolithic microwave integrated circuit (MMIC) power amplifier (PA) operating at L‐band with a power‐added‐efficiency (PAE) better than 70%. The MMIC PA is designed via load/source‐pull techniques to locate the optimal impedances at fundamental and harmonic frequencies on not only output but also input terminations. Moreover, rather than quarter wavelength stubs used in conventional designs, several parallel/series LC resonators are utilized to behave open/short at certain harmonics and to reform the drain waveform, yielding highly efficient performance of the PA MMIC. A prototype PA MMIC validating the proposed method is designed, fabricated and measured, which implemented on a 0.25 μm gallium nitride high electron mobility transistor technology. The measurement results of the PA under a drain voltage of 28 V at 1 ms pulse width with 30% duty cycle demonstrated a PAE better than 70% over 1.2–1.4 GHz with an output power greater than 40 dBm (10 W). The chip size is 2.5 mm × 3.5 mm (8.75 mm2).

A 75–305-GHz Power Amplifier MMIC With 10–14.9-dBm Pout in a 35-nm InGaAs mHEMT Technology

The demonstration of a 75-305-GHz power amplifier (PA) monolithic microwave integrated circuit (MMIC) is presented in this letter. The PA is based on an eight-cell traveling-wave unit amplifier (UA). Each cell contains an RF cascode with two two-finger transistors with a gate width of 20 μm each. In the output stage, a balanced configuration combines two UAs with Lange couplers. In front, a third UA is used as a driver amplifier. The PA MMIC is fabricated in a 35-nm gate-length metamorphic high-electron-mobility transistor technology. From 75 to 305 GHz, the PA yields a minimum output power of 10 dBm with an average value of 12.8 dBm. At 200 GHz, a peak output power and PAE of 14.9 dBm and 6.6% is achieved, respectively. To the best of the authors' knowledge, this is the first PA MMIC with an octave-bandwidth that provides an output power of 10 dBm at 300 GHz.

X-Band High-Efficiency Continuous Class B Power Amplifier GaN MMIC Assisted by Input Second-Harmonic Tuning

This paper presents a high-efficiency continuous class B power amplifier MMIC (Monolithic Microwave Integrated Circuit) from 8 GHz to 10.5 GHz, fabricated with 0.25 μm GaN-on-SiC technology. The Pedro load-line method was performed to calculate the optimum load of the GaN field-effect transistor (FET) for efficiency enhancement. Optimized by an output second-harmonic tuned network, fundamental to second-harmonic impedance, mapping was established point-to-point within a broad frequency band, which approached the classic continuous class B mode with an expanded high-efficiency bandwidth. Moreover, the contribution to the output capacitance of the FET was introduced into the output second-harmonic tuned network, which simplified the structure of the output matching network. Assisted by the second-harmonic source-pull technique, the input second-harmonic tuned network was optimized to improve the efficiency of the power amplifier over the operation band. The measurement results showed 51–59% PAE (Power Added Efficiency) and 19.8–21.2 dB power gain with a saturated power of 40.8–42.2 dBm from 8 GHz to 10.5 GHz. The size of the chip was 3.2 × 2.4 mm2.

Metal-Embedded Chip Assembly Processing for Enhanced RF Circuit Performance

This paper presents the radio frequency (RF) benefits of a heterogeneous integration technique for multi-chip modules. Passive components, such as lumped metal–insulator–semiconductor (MIS) and ceramic capacitors, as well as coupler circuits implemented on alumina substrates, are integrated in a metal-embedded chip assembly (MECA) process together with GaN monolithic microwave-integrated circuits (MMICs) in a way that provides a common RF and thermal ground. Simulations show that photolithographically defined interconnects can outperform wire bonds from 10 to 100 GHz. The interconnect layer of the MECA process forms bridge transmission lines with lower loss and comparable dispersion to microstrip lines, and with 35% higher characteristic impedances, validated by measurements up to 25 GHz. Microstrip Lange and branch-line couplers are designed partially on alumina and completed with MECA interconnects during the integration process, resulting in good performance in agreement with simulations. Finally, measurements of a GaN power amplifier (PA) MMIC integrated into the MECA process show gain and power-added efficiency (PAE) improvements of up to 3 dB and 3.2 percentage points, respectively.

A Three-Stage 18.5–24-GHz GaN-on-SiC 4 W 40% Efficient MMIC PA

This paper presents the design and measured continuous-wave (CW) performance of a three-stage $K$ -band monolithic microwave integrated circuit (MMIC) power amplifier (PA) implemented in a 150-nm GaN-on-SiC process. The transistor peripheries are staged at a ratio of 1:2:8, and the output stage consists of two reactively combined $8 \times 100~\mu \text{m}$ HEMTs with individual source vias. The measured peak output power is greater than 4 W with peak power added efficiency (PAE) of greater than 40%. The output power exceeds 3.2 W over the frequency range of 18–24 GHz with less than 1.5-dB variation. The three-stage architecture enables greater than 20 dB of saturated gain from 18.5 to 24 GHz. The bandwidth, output power, and efficiency performance are investigated as a function of output stage drain voltage. A statistical analysis for 230 die fabricated on five wafers is presented, and eight MMICs are mounted and characterized over power and frequency.

A Dual-Band GaN MMIC Power Amplifier With Hybrid Operating Modes for 5G Application

This letter implements a 3.5-/5.8-GHz dual-band power amplifier (PA) with hybrid operating modes for 5G mobile communication and vehicle network using a 0.25- $\mu \text{m}$ gallium nitride (GaN)-HEMT process. For the 3.5-GHz band, the PA operates in the Doherty mode, and the performance is optimized for a high back-off efficiency and a large bandwidth. For the 5.8-GHz band, the PA operates in class-AB mode, and optimal saturation efficiency is used as the design goal. According to the measurement results, a saturated power of 41.8–42.6 dBm, a saturated drain efficiency (DE) of 56%–64%, and a 6-dB back-off DE of 42%–51% are achieved from 3.3 to 3.8 GHz, while the saturated power and DE at 5.8 GHz are 41 dBm and 55%, respectively. To our best knowledge, this is the first dual-band GaN monolithic microwave integrated circuit PA designed for hybrid operating modes.

An X-Band 40 W Power Amplifier GaN MMIC Design by Using Equivalent Output Impedance Model

This paper presents an X-band 40 W power amplifier with high efficiency based on 0.25 μm GaN HEMT (High Electron Mobility Transistor) on SiC process. An equivalent RC (Resistance Capacitance) model is presented to provide accurate large-signal output impedances of GaN HEMTs with arbitrary dimensions. By introducing the band-pass filter topology, broadband impedance matching networks are achieved based on the RC model, and the power amplifier MMIC (Monolithic Microwave Integrated Circuit) with enhanced bandwidth is realized. The measurement results show that this power amplifier at 28 V operation voltage achieved over 40 W output power, 44.7% power-added efficiency and 22 dB power gain from 8 GHz to 12 GHz. The total chip size is 3.20 mm × 3.45 mm.

Design of Highly Linear Broadband Continuous Mode GaN MMIC Power Amplifiers for 5G

In this paper, we present a design approach for broadband harmonic-tuned monolithic microwave integrated circuit (MMIC) power amplifiers (PAs). Two harmonic matching networks are proposed for the realization of continuous class-B and class-F modes in an integrated PA. A design procedure is developed for integrated PAs using these matching networks to achieve high linearity, broadband operation, and compact chip area, in the presence of parasitic components and the physical limitations of the MMIC process. Two proof-of-concept fully integrated PAs are implemented in a 0.25-μm GaN-on-SiC process. Output power of 34.2-36.4 dBm with 40% to 49% power-added efficiency (PAE) is achieved in 4.2-7.0 GHz (51.6% fractional bandwidth), from the continuous class-B PA with only 1.5-mm 2 chip area. Furthermore, the continuous class-F PA achieves 36.2 dBm output power and 52% PAE at 5.0 GHz. The PAs are also characterized using QAM signals with wide bandwidth, in order to evaluate their performance for 5G wireless applications. For a 64-QAM signal with 100-MHz bandwidth and 8 dB peak-to-average power ratio (PAPR), the continuous class-B PA achieves 29.3 dBm average output power, 28% average PAE, and -25 dB (5.5%) error vector magnitude (EVM). The continuous class-F PA, tested using a 200 MHz 256 QAM signal with 8.5 dB PAPR, provides an average output power of 28.5 dBm, average PAE of 27%, and -28 dB (4%) EVM, without any pre-distortion.

Ka-Band MMIC Using AlGaN/GaN-on-Si With Recessed High- Dual MIS Structure

This letter reports the excellent radio frequency output characteristics of AlGaN/GaN-on-Si power amplifier (PA) monolithic microwave integrated circuits (MMICs) operating at the Ka-band, employing a recessed metal–insulator–semiconductor (MIS) structure with SiN x /HfON dual dielectric layers. The fabricated 0.15- $\mu \text{m}$ AlGaN/GaN-on-Si high electron-mobility transistor (HEMT) exhibited a low OFF-state current and reduced current collapse in comparison with the conventional Schottky gate HEMT; therefore, an enhanced output power of the PA MMIC is achieved. The fabricated two-stage PA MMIC exhibited a continuous-wave output power of >29 dBm with a power-added efficiency (PAE) of 14.5% at the drain voltage of 20 V, at 26.5 GHz.

A Compact Ultrabroadband Stacked Traveling-Wave GaN on Si Power Amplifier

The design and implementation of a GaN stacked distributed 2–19GHz monolithic microwave integrated circuit (MMIC) power amplifier (PA) is presented in this paper. The PA architecture uses six distributed cells, each containing a stack of three transistors. A design method that employs capacitance compensation is presented and applied to a 5–10-W PA design for the 2–19-GHz range in a 100-nm GaN on Si technology. The resulting measured performance at 28-V supply shows a gain flatness of 20.5 ± 1.5 dB, with an output power of 37.4–40.9 dBm and corresponding poweradded efficiency of 22%–49% over the entire frequency range. To the best of the authors’ knowledge, this is the first demonstration of a GaN on Si stacked distributed MMIC PA, with a die size of $2.8\times1.7$ mm2 and with a maximum power density of 2.58 W/mm2 over chip area.

A Prepulsing Technique for the Characterization of GaN Power Amplifiers With Dynamic Supply Under Controlled Thermal and Trapping States

The asymmetry between capture and release time constants associated with charge-trapping phenomena observed in the electrical characteristics of microwave gallium–nitride (GaN) field-effect transistors (FETs) introduces distortion in GaN-based power amplifiers (PA). The PAs that operate with supply modulation to increase efficiency are particularly affected by this phenomenon, since the GaN FET trap state exhibits a nonlinear dependence on the voltage applied to the device terminals. In this paper, a measurement approach and the setup are presented for a large-signal characterization of GaN-based PAs operated with dynamic bias supply: a new prepulsing technique is introduced, which enables the characterization of the PA in controlled charge-trapping and thermal states. The characteristics obtained with this technique are shown to give an accurate description of the PA performance in the actual application working conditions. The proposed approach is validated by using the measured data for the direct computation of predistortion functions for the linearization of a 9.7-GHz envelope tracking 10-W GaN monolithic microwave integrated circuit PA for amplitude-modulated pulsed radar transmitters. Additional research on the PA trap-induced performance degradation is also presented and can be explored to predict the PA performance for different parameters of the operative regime or for the formulation of the PA behavioral models.