MMIC Research Articles

Smart Spread Spectrum Modulated Tags for Detection of Vulnerable Road Users with Automotive Radar.

In recent years, there has been a significant increase in the number of collisions between vehicles and vulnerable road users such as pedestrians, cyclists, road workers and more recently scooter riders, especially in urban streets. This work studies the feasibility of enhancing the detection of these users by means of CW radars because they have a low radar cross section. Since the speed of these users is usually low, they can be confused with clutter due to the presence of large objects. To this end, this paper proposes, for the first time, a method based on a spread spectrum radio communication between vulnerable road users and the automotive radar consisting of modulating a backscatter tag, placed on the user. In addition, it is compatible with low-cost radars that use different waveforms such as CW, FSK or FMCW, and hardware modifications are not required. The prototype that has been developed is based on a commercial monolithic microwave integrated circuit (MMIC) amplifier connected between two antennas, which is modulated by switching its bias. Experimental results with a scooter, under static and moving conditions, using a low-power Doppler radar at a 24 GHz band compatible with blind spot radars, are provided.

High Linear and Temperature Insensitive GaAs Power Amplifier Operating at 3.3–3.6 GHz Using a Multi-Feedback Branch Bias Circuit

This letter describes a design of a 3.3–3.6-GHz GaAs heterojunction bipolar transistor (HBT) power amplifier (PA) with high linearity and temperature insensitivity for the fifth-generation (5G) of new radios (NRs). By involving a multi-feedback branches bias circuit, the voltage at the feedback node of the bias circuit can achieve dynamic self-tuning to stabilize the base voltage as the amplifier’s input power grows and stabilize the bias current as the temperature increases as well. A three-stage common source structure PA in the form of a monolithic microwave integrated circuit (MMIC) is designed using a multi-feedback branch bias circuit with a size of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.5\times1.2$ </tex-math></inline-formula> mm. Measured with continuous wave (CW) signals, the output 1-dB compression point at 3.3–3.6 GHz is 34 dBm. The linearity of the PA is also evaluated using a 5G-NR 100-MHz 64-quadratic-amplitude modulated (QAM)-orthogonal frequency division multiplexing (OFDM) signal with a 7-dB peak-to-average-power ratio (PAPR). The proposed PA achieves an adjacent channel power ratio (ACPR) less than −49.5 dBc at an average power of 28 dBm with a power-added efficiency (PAE) of 20% without the use of digital pre-distortion (DPD). In the temperature range of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$- 40\,\,^{\circ }\text{C}$ </tex-math></inline-formula> to 120 °C, the variance of bias current, small signal gain, PAE, output power at 1-dB compression point (OP1dB), and ACPR is relatively minor. This design is ideally suited for 5G communication systems due to its high linearity and temperature insensitivity.

MMIC Active Bandpass Filter With Nonreciprocal and Quasi-Elliptic Response

This letter details the design and validation of a monolithic microwave integrated circuit (MMIC) active bandpass filter (BPF) with nonreciprocal and quasi-elliptic-type response. Its architecture is based on cascaded active frequency-selective stages. Each stage is shaped by a resonant cell that introduces one transmission pole or one pole and two transmission zeros (TZs). The overall filter exhibits a three-pole/two-TZ response. Each stage is comprised of two FETs with a passive resonant cell connected between them. The FETs introduce gain to counteract the loss of the MMIC components. Due to their near-unilateral behavior, a nonreciprocal transfer function is obtained. Thus, the proposed device functions as a co-designed BPF/isolator. The operating principles of the active BPF are characterized through simulated examples. For validation, a GaAs prototype was developed at <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. It demonstrates a variable amount of gain in the forward direction of transmission and a highly isolated reverse transmission with >60 dB of isolation.

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 triband EBG loaded microstrip fractal antenna for THz application

Future wireless communication needs antenna with multifunctional operation. This paper focuses on Terahertz Antenna that could be easily integrated with micro and nano devices. In this paper, an octagonal shaped Microstrip Fractal Antenna loaded with the EBG structure is designed for tri-band terahertz application. Triple band characteristic achieved by fractal radiating patch is loaded with Electronic Band Gap (EBG). The antenna is working on triple band characteristics at 948 GHz, 984GHz and, 1040 GHz with overall dimensions of 700x900 µm2. The result and performance show that the recommended antenna will be compatible with compact wireless devices and Monolithic Microwave Integrated Circuit (MMIC). All simulation work has been done using electromagnetic software Ansoft High Frequency Structure Simulator (HFSS) and CST studio suite. The electromagnetic features like S11 parameters, VSWR, gain, efficiency and the radiation characteristics of such antenna are also explored. The simulation results show that this antenna has 9 dB realized gain at 0.948 THz resonating frequency.

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.

A Ka-Band Watt-Level High-Efficiency Doherty Amplifier MMIC in 90-nm GaAs Technology

This letter presents a Ka-band watt-level high-efficiency Doherty power amplifier (DPA) monolithic microwave integrated circuit (MMIC) in 90-nm gallium arsenide (GaAs) pseudomorphic high-electron-mobility transistor (pHEMT) technology. To realize the high efficiency of DPA at 6-dB power back-off (PBO), a low-loss compact Doherty output network is proposed to directly combine the matching network and the load modulation network (LMN) into a compact network. Then, the peaking amplifier of DPA is an optimized design to guarantee a sufficient load modulation at the 6-dB PBO level. The proposed DPA exhibits a measured saturation output power in the range of 29.5–30 dBm, with a corresponding peak power-added efficiency (PAE) in the range of 35%–40% from 26.5 to 30.5 GHz. Moreover, the PAE at the 6-dB PBO level of the proposed DPA is in the range of 25%–30.2% from 26.5 to 30.5 GHz.

Active Balun Design for Next-Generation Telecom Satellite Frequency Converters

In this work, we describe the complete design flow of a 1.3–3.3-GHz active balun, exploited to generate a high-voltage swing differential local oscillator (LO) signal driving a highly linear doubly balanced resistive ring mixer. Both the LO active balun and the mixer are integrated into a Ku-band single chip monolithic microwave integrated circuits (MMIC) downconverter for the state-of-the-art telecom satellites. System performance has been maximized designing the different circuits by a holistic approach, which considers a non 50- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Omega $ </tex-math></inline-formula> environment. The experimental validation is carried out by means of an ad hoc time-domain load–pull test bench and shows that the LO active balun provides two quasi-sinusoidal, 180° out-phased, signals with 2.4-V peak-to-peak voltage to the input ports of the mixer over a very high-impedance loading condition.

An improved 2×2 array antenna using both-sided microwave integrated circuit technology for circular polarization

&lt;span lang="EN-US"&gt;A circularly polarized microstrip patch array antenna using both-sided microwave integrated circuit (MIC) technology with a triple feed network has been proposed in this article. The antenna elements, feed structure and both-sided &lt;a name="_Hlk112828933"&gt;&lt;/a&gt;MIC technology are used and arranged in such a way to obtain circular polarization alongside high gain without using an external matching circuit. The 50 Ω microstrip line is used to energize the antenna where the antenna’s total feed network is made up of both series and parallel combinations of microstrip and slot line. The antenna was realized using Teflon glass fiber substrate &lt;/span&gt;&lt;em&gt;&lt;span lang="EN-US"&gt;(ε&lt;sub&gt;r&lt;/sub&gt;)&lt;/span&gt;&lt;/em&gt;&lt;span lang="EN-US"&gt;=2.15 with a thickness of 0.8 mm. The antenna has some splendid parameters including S&lt;sub&gt;11&lt;/sub&gt; of less than -35 dB, a gain of 12 dBi with an omnidirectional pattern and an axial ratio of 0.7 dB at the operating frequency. The antenna possesses a bandwidth of 430 MHz (4.22%) after operating at X-band in the frequency spectrum. The antenna’s simulated parameters were investigated with the help of advanced design system (ADS) simulation software in microwave momentum mode.&lt;/span&gt;

Design of Front-End Receiver and Matrix for 2–18 GHz with a Searching and Tracking Function for an ELINT System

In this paper, we describe the design and fabrication of a front-end receiver and matrix modules for 2−18 GHz with high gain, good phase matching characteristics, and reliability; this was accomplished by applying a chip-and-wire process using a bare-type monolithic microwave integrated circuit (MMIC) device. To compensate for the mismatch among many sub-modules, a front-end module, matrix module, and built-in test module suitable for sub-band frequency characteristics were designed and applied to the direct receiver. The matrix box used a high-pass filter to remove unwanted low frequencies and a 4-way divider to distribute single input BIT signals. The broadband receiver module had two paths: a phase path and an amplitude path. Phase- and amplitude-matched radio frequency semi-rigid cables of different lengths were used to connect to the internal sub-modules of the matrix receiver. The main RF line was a dielectric substrate, RT/Duroid 5880, with a relative dielectric constant of 2.2 and a dielectric thickness of 0.127 mm. The sizes of the front-end receiver and matrix box were 137 mm × 120 mm × 31 mm and 250 mm × 238 mm × 138 mm, respectively. In the wideband frequency receiver module, the gain was 22.99 dB at mid-band (frequency 2−6 GHz) with a return loss of about 14.76 dB. Th e gain was 23.25 dB at a high band (frequency 6−18 GHz), having a return loss of about 11.63 dB. The peak values of phase matching among the channels for 2–6 GHz were ±3.30°, and the peak values of phase matching among the channels for 6–18 GHz were ±8.24°.

A Wire-Bonded Patch Antenna for Millimeter Wave Applications

Wire bonds are one of the most common interconnects used in microelectronics; however, their application to millimeter wave monolithic microwave integrated circuits (MMICs) may severely decrease the overall system performance due to transmission loss, radiation loss, and impedance mismatch. The goal of this work was to optimize a wire-bonded patch antenna to minimize losses and maximize the gain in the frequency range from 81 to 83 GHz. Optimization was based on electromagnetic simulations of different variants of the wire bond. Results show that the optimized structure demonstrates two major advantages. Firstly, it does not require any external matching network; hence, it can be directly connected to a contact pad of an MMIC die. Secondly, the wire bond radiation effect is utilized to enhance the patch antenna gain at the broadside direction.

A 20‐W wideband voltage controlled attenuator for millimeter‐wave applications

In this paper, we present a distributed voltage controlled attenuator (VCA) featuring an extremely high power handling capability of 20 W. Theoretical analyses have been performed to simultaneously achieve a wideband, low insertion loss, and high attenuation dynamic range performance. Implemented in a commercial 0.25-μm GaN-on-SiC high electron mobility transistor (HEMT) technology, a 1- to 25-GHz VCA was measured to perform a dynamic range of 24 dB, an average insertion loss of 3.4 dB, and an average input 1-dB compressed power (P1dB) of 43 dBm across the frequencies of interest. To the best of the authors' knowledge, this paper presents the monolithic microwave integrated circuit (MMIC) VCA with the reported highest power handling capability in such compact chip area, while maintaining a nice operating bandwidth and dynamic range.

Design and Analysis of MSPA using FR-4 Epoxy Dielectric for Wireless Broadband Application

In modern communication devices, microstrip patch antennas are preferred to conventional antennas due to their size. In this review, a survey of commonly used techniques and designs for microstrip antennas is conducted. These techniques and designs were used by the authors to design an effective, low-profile, small, compatible, and affordable microstrip antenna. They were mostly used to design reconfigurable, multiband, and wideband antennas. After that, a initiator patch design with dimensions is provided on which technique will be used to analyze various antenna parameters. In recent years, research into microstrip patch antennas has made significant progress. Microstrip patch horns outperform conventional microstrip patches in a number of ways, including their low cost, ease of integration with integrated microwave circuits (MICs), low volume, small size, high performance, and low weight.

A 2-V 1.4-dB NF GaAs MMIC LNA for K-Band Applications.

A 1.4-dB Noise Figure (NF) four-stage K-band Monolithic Microwave Integrated Circuit (MMIC) Low-Noise Amplifier (LNA) in UMS 100 nm GaAs pHEMT technology is presented. The proposed circuit is designed to cover the 5G New Release n258 frequency band (24.25-27.58 GHz). Momentum EM post-layout simulations reveal the circuit achieves a minimum NF of 1.3 dB, a maximum gain of 34 dB, |S11| better than -10 dB from 23 GHz to 29 GHz, a P1dB of -18 dBm and an OIP3 of 24.5 dBm. The LNA draws a total current of 59.1 mA from a 2 V DC supply and results in a chip size of 3300 × 1800 µm2 including pads. We present a design methodology focused on the selection of the active device size and DC bias conditions to obtain the lowest NF when source degeneration is applied. The design procedure ensures a minimum NF design by selecting a device which facilitates a simple input matching network implementation and obtains a reasonable input return loss thanks to the application of source degeneration. With this approach the input matching network is implemented with a shunt stub and a transmission line, therefore minimizing the contribution to the NF achieved by the first stage. Comparisons with similar works demonstrate the developed circuit is very competitive with most of the state-of-the-art solutions.

An Efficient 24-30 GHz GaN-on-Si Driver Amplifier Using Synthesized Matching Networks.

This paper presents a broadband GaN microwave monolithic integrated circuit driver amplifier (MMIC DA) with compact dimensions of 1.65 mm × 0.78 mm for 5G millimeter-wave communication. The optimal impedance domain satisfying the preset goals was first acquired using the simplified load-pull procedure and small-signal simulations, followed by a weighted average method to determine the reference center matching point from which the optimal intrinsic load can be deduced. By means of de-embedding load-pull contours, modeling based on theoretical analysis, and simulation fitting for parameter identification, the nonlinear output capacitance and a series RLC model circuit approximating the input impedance response of the stabilized transistor were extracted. Under the design principle of fully absorbing the parasitic parameters of the device, explicit formulas and tabulated methods related to the Chebyshev impedance transformer were applied to construct filter-based synthesized matching networks at each stage and finally convert them into an implementable mixed-element form via the single-frequency equivalence technique. Measured on-wafer pulsed results for the proposed two-stage DA across 24-30 GHz demonstrated up to 31.1 dBm of saturated output power (Psat) with less than 1 dB total fluctuation, 19.3 ± 1 dB of small-signal gain, and 39.8% of peak power-added efficiency (PAE) at the mid-frequency.

Accurate Simulation of High-Gain MMIC Amplifiers With Microstrip-Type Transistors

A discrepancy of monolithic microwave-integrated circuit (MMIC) amplifier simulations is discussed for conventional electromagnetic (EM) circuit co-simulation in advanced design system (ADS). An obvious discrepancy occurs when microstrip (MS) type transistor schematic models are used in a high gain MMIC amplifier. The coupling effect of a backside via hole in the MS-type model, which is excluded from EM layout simulation, is demonstrated to be the root of this error that will become significant in high-gain MMIC amplifier design. A new method is proposed to include a source via hole of the MS-type transistor in MMIC layout EM simulations. Simulation experiments confirm that this new method can significantly improve the EM simulation accuracy when including a transistor source via hole in the circuit layout EM simulation. The intercoupling effect of the transistor source via is investigated on the correlation with frequency, current gain, via separation distance, and substrate thickness.

Nonlinear and Load-Pulling Effects in an Octave-Bandwidth Transmit Array

This article presents the design and nonlinear analysis of an octave-bandwidth transmit in-phase power combiner feed network. The goal is to evaluate the effect of nonlinearities on the in-phase spatial power combiner figures of merit (FoMs), namely effective isotropically radiated power (EIRP), overall efficiency, and linearity across a wide bandwidth and as a function of active antenna impedance and power amplifier (PA) supply voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\textrm {DD}}$ </tex-math></inline-formula> ). The analysis is showcased on a 6–12 GHz four-element array implemented with electrically small flared horns fed with microstrip-to ridge waveguide transitions, 2-W commercial gallium nitride (GaN) monolithic microwave integrated circuit (MMIC) amplifiers, and an in-phase Wilkinson power splitter. Over-the-air (OTA) measurements show an EIRP of 50 dBm over the octave bandwidth. Adjacent channel power ratio (ACPR) variation over frequency, power, and supply voltage is also measured through OTA and shows a variation of 10 dB over the considered variables.

25–31 GHz GaN-Based LNA MMIC Employing Hybrid-Matching Topology for 5G Base Station Applications

This letter presents a gallium nitride (GaN) high electron mobility transistor (HEMT)-based three-stage low noise amplifier (LNA) monolithic microwave integrated circuit (MMIC) that can apply to the fifth-generation (5G) new radio base station applications. The designed GaN-based LNA MMIC utilizes a hybrid-matching topology with double-shunt capacitors at input and output (I/O) matching networks to achieve broad return loss (RL) and bandwidth characteristics across 5G frequency range two bands. The design is fabricated in a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.15~\mu \text{m}$ </tex-math></inline-formula> GaN on silicon carbide technology and attains small signal gains greater than 21 dB, noise figures of 2.4–2.9 dB, 1-dB compression points greater than 19.1 dBm, output third-order intercept points greater than 28.5 dBm, and I/O RLs greater than 10 dB at 25–31 GHz band. The implemented design consumes a power of approximately 300 mW.

DESIGN OF X-BAND MMIC LOW-NOISE AMPLIFIER IN GAAS-BASED 0.5 UM PHEMT TECHNOLOGY

One of the most important functional units of the receiving tract as part of the transceivers is a Low-Noise Amplifier (LNA). This paper presents the design process of a X-band (8…12 GHz) Microwave Monolithic Integrated Circuit (MMIC) LNA. The design was carried out using the Process Design Kit of the GaAs-based pHEMT05D technological process of JSC «Svetlana-Rost». The active nonlinear elements in this technological process are depletion mode pseudomorphic high electron mobility transistors with a 0,5-microns gate length.

Сверхширокополосный pin-диодный диплексерный переключатель на GaAs

The article presents a circuit of an ultra-wideband pin-diode switch for two channels with different operating frequency ranges: DC-18 GHz and 18–26.5 GHz. A topology model of a microwave monolithic integrated circuit (MMIC) based on quasi-vertical GaAs pin diode technology of Miсran JSC is described. Comparison of simulation results and experimental measurement data of manufactured MMICs is performed. The use of the integrated circuit of the switch is possible as a part of the switching nodes of the measuring microwave equipment.