In this letter, we propose a novel technique for rapid and accurate yield estimation of microwave passive components using model-order reduction (MOR)-based neuro-transfer function (neuro-TF) models. In the proposed technique, the frequency responses of microwave components are represented by transfer functions in the pole-zero-gain format. The poles, zeros, and gain in the transfer functions are computed

The absorbing boundary condition (ABC) is very common to be used to truncate the computational domain in the hybridizable discontinuous Galerkin (HDG) method. However, if solving waveguide transmission problems with multimode scattering, the ABC is not very applicable due to the wave impedances varying with the frequency. Considering the perfectly matched layers (PMLs) boundary can absorb well the

This letter proposes a new surrogate-based multiphysics optimization technique for microwave devices incorporating artificial neural networks (ANNs) and trust-region algorithm. In the proposed technique, at each optimization iteration, we build an accurate and efficient ANN surrogate model using multiple multiphysics training samples around the optimized solution from the previous iteration. A parallel

Nonradiative dielectric waveguide (NRD guide) is a promising platform for realizing compact millimeter waveguide circuits. NRD guide devices have been simulated by several numerical simulation approaches so far and these approaches treat 3-D structure because electric and magnetic fields in NRD guides vary in whole directions. In this letter, we propose a 2-D full-vectorial finite element analysis

Optically transparent conductors (TCs) have been implemented and adopted into next-generation transmission lines and other RF structures from UHF to millimeter-wave (mmWave) applications. A current method of evaluating the performance of optically TCs uses a figure of merit (FOM) which is frequency agnostic. A new FOM for optically TCs at RF, microwave, and millimeter-wave frequencies is presented

In this letter, a compact wideband bandpass filter (BPF) with a wide stopband is proposed based on the substrate integrated defected ground structure (SIDGS) and folded stepped-impedance resonator (FSIR). Such a SIDGS resonator can not only allocate a specific resonance with compact size but also introduce the different harmonic positions compared with a traditional microstrip line resonator. Meanwhile

In this letter, a novel reconfigurable filter concept, which is called assembly reconfigurability through rotation, is proposed for the first time to implement a high-Q filter with adjustable frequency response. Two separated printed circuit boards (PCBs) are designed and assembled together to build a double-layer substrate integrated waveguide (SIW) filter. Guided by coupling matrix synthesis, the

This letter presents the design of compact triple- and quad-band power dividers (PDs) based on substrate integrated waveguide (SIW) technology. The proposed PDs are designed as a rectangular cavity, one pair of unequal complementary split-ring resonators (CSRRs) and U-shaped slots (USSs). Initially, a dual-frequency SIW PD is implemented using unequal CSRRs on the top surface of the SIW cavity. This

In this letter, a novel design of a narrow bandpass frequency selective surface (FSS) based on the utilization of the coupled method, which resonates at Ka -band frequencies between 29 and 30.3 GHz, is proposed and experimentally evaluated. A high selectivity was achieved, by coupling two metallic layers, which were based on the structure of a cross aperture and a rectangle grid patch, respectively

In this letter, we present an innovative filter configuration employing transversal coupled triple-mode spherical resonators while capable of realizing transmission zeros (TZs). Transversal coupling involves simultaneous source and load-controlled couplings to all the three modes of the spherical resonator. Spherical resonators inherently have very large quality factor (Qu) and exhibit a farther spurious

Modeling the temperature-dependent nonlinearity of intrinsic capacitances in AlGaN/GaN high electron mobility transistors (HEMTs) improves model accuracy. In this letter, extraction results indicate that the current modeling methods cannot accurately reflect the variations of nonlinearity in intrinsic capacitances with temperature. This letter analyzes the causes of unmodeled phenomena and characterizes

This letter introduces for the first time a fully integrated analog vectorial modulator (VM) in gallium nitride on silicon (GaN-on-Si) monolithic microwave-integrated circuit (MMIC) technology, operating in $Ka$ -band, and an analytical calibration technique suitable for VM. An extensive characterization of the prototype, with both static and dynamic modulating signals, validates both the design and

In this letter, a novel reconfigurable 0°/90° phase shifter is proposed. Compared with the conventional phase shifters, the proposed one uses fewer reconfigurable devices and becomes more compact. Two states of a meander line are used to generate the 90° phase shift, making it suitable for the 2-D beam steering 2-bit array application. A phase shifter prototype on F4B was measured to validate its design

This letter presents a multiband switchable low-noise amplifier (LNA) in the 0.1- $\mu \text{m}$ GaAs pHEMT process. Employing a new varactor-based tunable network as the interstage matching circuit, the operation bands can be tuned consecutively and cover the 5G millimeter-wave frequency bands N257/N260. The proposed tunable structure functions well without sacrificing noise performance or increasing

One high-efficiency power amplifier (PA) with a novel multiharmonic tuning (HT) network is presented. The second and third harmonic impedances are simultaneously controlled with a simple offset double-sided parallel strip line (DSPSL)-based output-matching network. Based on the above strategy, high PA efficiency can be achieved by mapping the fundamental and harmonic impedances to the optimum positions

A ${K}$ -band variable-gain phase shifter using a Gilbert-cell vector synthesizer with a current digital-to-analog converter (DAC) and an RC – RL poly-phase filter (PPF) is presented, which is fabricated with a 65-nm RF CMOS process. It controls both gain and phase with low phase and gain variations as well as a low insertion loss. The Gilbert cell synthesizes a vector by summing in-phase (I) and quadrature

This letter presents a novel harmonic impedance matching technique by using a parallel LC resonate block after the combining point to design a fully integrated high-efficiency Doherty power amplifier (DPA). The second harmonic impedances of both carrier and peaking amplifiers can be matched to the optimal area with only one harmonic tuner easily. The insertion loss and size of the output matching network

This letter presents a microwave amplifier (MA) with a substrate integrated waveguide (SIW) bandpass filter (BPF) output matching network (OMN). The codesigned amplifier and SIW BPF with complex termination impedance (CTI) can reduce the circuit size and the design complexity while improving loss. To match the CTI of the SIW BPF, the frequencies of the first and/or last resonators must be detuned.

We show that fast technical fluctuations of microwave signals can be strongly suppressed by cryogenic resonators. The experiments were carried out with sapphire resonators cooled to approximately 6 K at frequencies around 11 GHz. Each sapphire crystal was shaped like a spindle with the rotational and crystal axes aligned within a degree. Noise suppression factors in excess of 50 dB were measured at

We report a single broadband on-wafer resistance calibration standard fabricated with a 15-nm-thick gold resistor on an alumina substrate. Because the resistor film is much smaller than the skin depth at microwave frequencies, this proposed standard demonstrates excellent stability over both frequency and temperature when compared to traditional calibration resistors. A variety of resistors were fabricated

A method to detect people in multiple locations using a multiple-input and multiple-output (MIMO) frequency-modulated continuous wave (FMCW) radar system is proposed. A 2-D range-angle map is estimated by digital beamforming with virtual receiver arrays obtained via the operation of time-division multiplexing (TDM) MIMO radar. Phase variations due to human vital signs and movements allow the identification

This work presents a new RF power amplifier characterization technique based on a Gaussian pulse, which is shown to approximate the envelope of a multicarrier signal with 0.5% error around the peaks. The standard deviation of the Gaussian pulses is inversely proportional to the $I/Q$ signal bandwidth. This test signal is shown to accurately capture nonlinear memory effects that result in gain dispersion

Presents the table of contents for this issue of the publication.

Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.

This work describes a new strategy for improving the peak power handling capability (PPHC) of microstrip bandpass filters (BPFs) without any degradation in the electrical performance. For this purpose, a new resonator topology with rounded open-circuit terminations is proposed. Using this strategy, sharp edges are avoided, and a reduction of the maximum peak voltage ( $V_{\mathrm{peak}}$ ) is obtained

A spiral-coupled-line-based Ka -band (26.5–40 GHz) CMOS Wilkinson power divider with a shunt capacitor (C) at the input and a shunt RC (or C) between the outputs is reported. The spiral coupled line, i.e., two noninverting spiral transmission lines (TLs) with magnetic coupling, has a positive mutual inductance. This leads to a significant TL-length reduction (from about $\lambda $ /7 to $\lambda $

A novel miniaturized bandpass filter (BPF) with high stopband rejection based on a hybrid structure is proposed with shielded quarter-mode substrate integrated waveguide (QMSIW) and microstrip technologies. The shielded QMSIW cavity provides a high-quality ( $Q$ ) factor with substantial size reduction. This filter exhibits flexible response with four poles and two controllable transmission zeros (TZs)

In this letter, a single-layer bandpass frequency selective surface (FSS) working at 2.6 GHz is proposed to decrease the interference to communication systems and the cost of processing based on a multimode resonator. A metasurface unit cell is adopted to suppress the grating lobe and achieve miniaturization. Therefore, the performance of the proposed FSS can remain stable under a large oblique incidence

This letter proposes a new design method of dual-band filtering differential phase shifter using cascaded wideband phase shifter and bandstop network. After cascading the bandstop network, the phase shift characteristic of the initial wideband filtering differential phase shifter remains unchanged, while its wide passband is divided into dual subpassbands. Compared with traditional dual-band-filter-based

A qualitative method to verify the presence of parametric oscillations at ${f_{0}}/{2}$ in power amplifiers (PAs) is presented and validated. It relies on the simultaneous application of fundamental and subharmonic tones to trigger possible parametric oscillations and can be implemented in any commercial harmonic balance solver without requiring any external software that may be expensive or however

A $W$ -band balanced frequency doubler with an optimized harmonic termination and neutralization technique is proposed for high output power and high conversion efficiency in a 90-nm SiGe process. The proposed design demonstrates a peak conversion gain of 0.7 dB and the maximum output power higher than 4 dBm at an output frequency of 84 GHz with the conversion efficiency of 14%.

A 28-GHz high linearity active up-conversion mixer using 28-nm CMOS is presented in this letter. To enhance the modulated output power level under high-order modulation with IM 3 improvement in the high IF input power region, the second-order intermodulation (IM 2 ) signal injection technique is adopted. The positive third-order intermodulation (IM 3 ) signal is generated by mixing the IM 2 signal

This letter presents single-ended and differential $D$ -band power amplifiers (PAs) in 55nm SiGe BiCMOS technology. The proposed PAs exploit the remarkable features of common-base stages for rising the power efficiency, i.e., 1) higher breakdown voltage; 2) sharp compression profile due to the enhanced linearity; and 3) supply current adapted to the signal amplitude by means of current clamping. A

This letter proposes a high output power 250-GHz power amplifier adopting dual-shunt elements in the implementation of maximum achievable gain ( $G_{\mathrm {max}}$ ) core. By the adoption of the dual-shunt-element-based $G_{\mathrm {max}}$ -core, the output transistor size can be increased, which leads to higher output power. Implemented in a 65-nm CMOS, the measurement results show a peak gain of

A high-isolation fully integrated 26.5–36.2-GHz frequency-division duplex (FDD) transmit–receive (T/R) duplexer (DUX) front-end module, containing DUX, power amplifier (PA), and low-noise amplifier (LNA), for fifth-generation (5G) wireless systems is demonstrated on a single 0.18- $\mu \text{m}$ BiCMOS Si chip. The isolation between the PA output and LNA input is generally better than 40 dB from 15

This letter presents the design and experimental characterization of a $K$ -band high power amplifier (HPA) monolithic microwave-integrated circuit (MMIC) for the next generation of very high throughput satellites (vHTS). The MMIC is a three-stage balanced amplifier realized on a commercial 100-nm gate length gallium nitride on silicon (GaN-Si) technology. The design is compliant with space reliability

A Si-based series-shunt transmit/receive (TX/RX) switch with a high-power 1-dB compression point ( $P_{\text {1 dB}}$ ) of 29.2 dBm is demonstrated at 28 GHz for 5G communication. The proposed switch also exhibits low insertion losses of 2.86 dB/3.46 dB and reasonable isolations of 21.7 dB/19.1 dB for TX/RX modes, respectively. These excellent results were achieved by applying an LC resonator and stacked

Connectors are significant contributors to passive intermodulation (PIM) in microwave systems. In this letter, a generalized network method is presented for evaluating the PIM from multiple connectors. Taking a structure composed of two connectors and a transmission line as an example, a generalized network model describing both linear and nonlinear relationships is developed and an expression of the

A monopulse feeding network is proposed for transmitting and receiving time-domain short pulse with high fidelity. The network consists of coplanar waveguides (CPWs), slotlines, microstrip lines, and transitions. Both the sum and the differential performances of the network depend mainly on the transverse structures of these transmission lines rather than their lengths, providing the capability of

A microwave method has been proposed for constitutive parameters’ extraction of samples on a known substrate. The advantage of this method is that it relies on noniterative reflection-only (air- and metal-backed) scattering (S-) parameters so that it is a good candidate for the characterization of samples when only one-port measurements are available. It is validated by the $X$ -band (8.2–12.4 GHz)

This letter presents a broadband self-driving radio frequency-to-direct current (RF-dc) rectifier design realized on the CG2H40010F Cree’s GaN device. First, the transistor modeling parameters for the reverse-biased $I$ – $V$ characteristics have been obtained to achieve the high-frequency rectification at negative drain biasing. Besides, an enhanced self-synchronization is achieved across the operating

The frequency-dependent complex permittivity is determined for a printed circuit board laminate. For this purpose, measurements performed to an array of striplines are systematically processed. The methodology presents the advantage of employing lines embedded within the same laminate without requiring multiple prototypes. From the extracted data, a Debye model is implemented to yield a wideband representation

Prospective authors are requested to submit new, unpublished manuscripts for inclusion in the upcoming event described in this call for papers.

These instructions give guidelines for preparing papers for this publication. Presents information for authors publishing in this journal.

Presents the table of contents for this issue of this publication.

Provides a listing of current staff, committee members and society officers.

In this letter, a compact dual-band dual-mode substrate integrated waveguide (SIW) balanced band-pass filter (BPF) with intrinsic common-mode (CM) suppression is designed by using a single perturbed SIW circular cavity. The vias and slot perturbations are introduced to tune the resonant modes TE 010 , TE 110 (a pair of degenerate modes), and TE 210 of a circular cavity. Thus, they can be used to form

A methodology for tunable bandpass filters (tBPFs) with one switchable transmission zero (TZ) is presented, wherein the frequency tuning and TZ switching can be simultaneously achieved by merely tuning the resonant frequencies of resonators. Theoretically interpreted by coupling matrices with arbitrary filtering orders ( $n \ge 2$ ), the TZ can be symmetrically switched between lower and upper sides

In this letter, a new compact filtering power divider (FPD) on the square substrate integrated waveguide (SIW) with wideband isolation is proposed. As the isolation network is embedded in a square SIW cavity, good in-band isolation, compact structure, and low insertion loss can be simultaneously attained. The proposed FPD consists of the coplanar waveguide feeding line of Port 1, the capacitor, a resistor

A two-section broadband coupler with wide-range phase differences and power-dividing ratios is proposed. Closed-form design equations for the proposed couplers are derived. For verification, two couplers I and II operating at 2 GHz with phase difference of 45° and power-dividing ratio of 1, and phase difference of 60° and power-dividing ratio of 2, respectively, are fabricated and measured. For the

We propose a new tunable coupler with flexible coupling direction and a wide power division ratio (PDR) tuning range. The structure consists of two 90° hybrid couplers with two reconfigurable synthesized transmission lines (RSTLs) inserted in between. The RSTL is designed to operate either in the passband as an analog phase shifter or in the transition region and stopband as a mismatched circuit with

This letter presents a $4 \times 4$ Butler matrix realized using stereolithography 3-D printing technology and liquid metal filling. The matrix is in coaxial technology and relies on circular branch lines and curved $50~\Omega $ lines. Input and output ports are aligned and placed on the same plane, while branch lines are organized using all three dimensions to minimize the length of the connecting

A compact double-sided contactless electromagnetic bandgap (DCEBG) structure is introduced in this letter. It consists of three metal plates placed in parallel, including two smooth metal plates and a corrugated metal plate in the middle. The middle plate is double-sided corrugated alternatively with a displacement of half period. The depth of the corrugations is about quarter wavelength of center

A wideband terahertz (THz) output network consisting of a pyramidal horn and a diamond Brewster window has been developed for 0.7–1.0-THz traveling-wave tube (TWT) amplifier and is measured at 0.325–0.5 THz owing to the limitation of the measurement facility. A pyramidal horn is designed to convert the waveguide mode into a high-purity quasi-plane polarized mode to meet the demand of the Brewster window

This letter proposed a combined susceptibility diagram, applicable to investigating and differentiating the inherent mechanism of multipactor in dielectric-loaded microwave devices. This susceptibility diagram consists of average secondary emission yield on the dielectric surface and both the surfaces. Using this diagram, we predict the electron multiplication mechanism in the partially dielectric-loaded

The power amplifier (PA) behavior models based on deep neural networks (DNNs) have been widely used. However, it is challenging to balance the network depth, the number of neurons, and the combination of input terms. Accordingly, how to obtain a suitable DNN model becomes a problem. This letter proposes a method to acquire the corresponding optimal DNN structure balancing multiple aspects for a PA

This letter presents a simple method to design dual-band high-efficiency power amplifiers (PAs). The dual-band coupler is exploited to design the output circuits of the PA. By proper selection of impedance conditions of terminal ports, the dual-band coupler can convert the fundamental impedance of transistor to the standard 50- $\Omega $ load at two frequencies. At the same time, the second harmonic

A Ka -band monolithic low-noise amplifier (LNA) with high gain and high dynamic range (DR) has been designed and implemented in a 100-nm gallium nitride (GaN)-on-Si technology. The LNA is designed as the first stage of a high DR receiver in an frequency modulated continuous wave (FMCW) radar for the detection of small drones. The three-stage monolithic microwave integrated circuit (MMIC) LNA has a

A broadband process, voltage, and temperature (PVT)-insensitive noise-canceling balun-low-noise amplifier (LNA) was implemented in the 0.13- $\mu \text{m}$ CMOS process for subgigahertz wireless communication applications. The proposed LNA is based on the traditional common-gate common-source (CGCS) balun-LNA topology, and it adopts the diode-connected loads to reduce the noise contribution originated

A variable gain distributed amplifier (VGDA) for the Rx path of ultrawideband phased-array system is implemented in 90-nm CMOS process and presented in this letter. In order to achieve high gain and wideband with relative low dc power dissipation ( $P_{\mathrm {dc}}$ ), the combination of the conventional distributed amplifier (CDA) and the cascaded single-stage distributed amplifier (CSSDA) is utilized