An optimum approach for designing a TE 01 mode oversized waveguide bend is proposed based on angular-deformed circular waveguide. Due to the deformation of the circular waveguide cross section, the degeneracy of the TE 01 mode and the TM 11 mode is removed, and the mode conversion inside the waveguide bend is weakened. Characterizations of the angular-deformed circular waveguide with different deformation

The reflection and transmission of guided mode in the 2-D single-mode waveguide whose boundary is random shape is numerically simulated. Since the boundary element method based on the guided-mode extracted integral equation (GMEIE) is employed, the boundary condition on the random boundary is rigorously satisfied. The dependence of the transmission coefficient on the amplitude of the random boundary

An advantage of time-domain electromagnetic simulation tools is that an entire spectrum can be obtained in a single simulation run by using a broadband initial condition and Fourier transformation of the ensuing time sequences. However, when the simulation involves time-varying materials, the system is no longer time-invariant, and Fourier techniques must be reconsidered to obtain desired results.

Neural network-based capacitance models are accurate, but some of them are not charge-conservative. In this work, a novel consistent gate charge model for GaN high electron mobility transistors is presented based on neural networks. The equivalent circuit parameters are extracted using the multiobjective gray wolf optimizer-based hybrid method, which improves the accuracy of parameter extraction. To

In this work, we propose a new concept of phase shifting by tuning the coupling distance between two parallel silicon slabs that support the propagation of an in-phase supermode. A prototype device was implemented in the 220–330-GHz band by integrating the micro-electro-mechanical system (MEMS)-actuated phase-shifting mechanism, based on two moveable parallel-coupled high-resistivity silicon slabs

A novel (patent pending) waveguide orthomode transducer (OMT) design is presented. The use of a common waveguide cross section with twofold rotational symmetry is proposed to mitigate the typical drawbacks of a two-probe OMT geometry. In particular, the cross-polarized electric field component may be reduced by introducing a twofold rotationally symmetric cross-sectional design with slant axes in the

In this article, a single-ended-to-balanced (SETB) broadband magic-T based on microstrip/slotline transitions and microstrip/slotline T-junctions is proposed. For the purpose of miniaturization and low interconnection loss, an SETB filtering magic-T with a sharp selectivity is also achieved by introducing a pair of microstrip stub-loaded resonators (SLRs) at the two output ports. For the first design

In this work, we present the first group of gigahertz low-loss, wideband, and high power handling delay lines (ADLs) using a thin-film lithium niobate (LiNbO 3 )-on-sapphire platform. The ADLs leverage a single-phase unidirectional transducer (SPUDT) to efficiently excite the shear horizontal surface acoustic wave (SH-SAW) in the film stack. The fabricated miniature SH-SAW ADL at 1.1 GHz shows a low

This article reports on the design and practical development of RF co-designed MMIC components that exhibit the function of a bandpass filter and an RF isolator. They are based on cascaded non-reciprocal frequency-selective stages (NFSs), one-pole/two-transmission zero (TZ) multi-resonant stages, and impedance inverters. The combination of these components results in a two-port network that exhibits

This article presents an analytical method for the synthesis of a low-pass prototype filter constituted by cascaded ${n}$ -tuplets, including resonant node (RN) and nonresonant node (NRN). The method extends the features of previously published solutions, limited to RNs only or that allow the inclusion of NRNs but in rigid configurations. The method begins with extracted-pole synthesis, arbitrarily

In this article, we describe several alternative inline implementations for combline filters with transmission zeros (TZs) located both below and above the passband. A systematic design procedure is also presented using a lumped-element equivalent circuit. Following the design procedure that we propose, up to $N+1$ TZs can be implemented with an inline filter of order $N$ . The generation of the TZs

In this article, a novel $n$ -way topology is proposed to design a class of multiway wideband filtering power dividers (FPDs). It consists of $n$ -coupled multimode resonators and $n$ resistors. To achieve a wideband filtering response, the stub-loaded multimode resonator is first employed. A good port–port isolation can then be obtained by electrically connecting the original open end of the two half-wavelength

This article presents an analytical design for millimeter-wave monolithic microwave integrated circuit (MMIC) switches. First, the field-effect-transistor-based (FET-based) resonator is proposed, whose resonant frequency and bandwidth can be controlled flexibly. As a result, the design flexibility of MMIC switches can be highly improved by using FET-based resonators. Second, a fast and flexible impedance

This article presents the analysis and design of a Class- $\text{E}_{\mathrm {M}}/\text{F}_{\mathrm {n}}$ power amplifier (PA). The high peak switch voltage factor of the classical Class- $\text{E}_{\mathrm {M}}$ PA is reduced by 27.3% through the adoption of the Class- $\text{F}^{-1}$ third-harmonic termination on the main circuit, resulting in a novel topology called the Class- $\text{E}_{\mathrm

A wideband low-noise amplifier (LNA) featuring transformer-based wideband input matching is proposed for millimeter-wave applications. By analyzing the properties of conventional series input matching networks, which were widely employed in narrowband LNAs and shunt–series matching networks for bandwidth extension, a novel input matching network possessing the merits of both was proposed. For further

Near-field scanning microwave microscopy is a technique with increasing popularity for the study of nanometer-scale electrical properties of samples. Here, we present an approach to quantify sample properties in images obtained with an inverted scanning microwave microscope (iSMM), recently introduced by our group. In particular, this study reports the analysis of the local electrical conductivity

A scalable planar 2-D active array antenna configuration that can realize amplified radiation through co-existing active devices is proposed, studied, and demonstrated in this work. The input and output of these amplifying active devices are directly integrated with the feed network and array elements, respectively, thereby eliminating the matching networks typically required in an amplifier circuit

Class-E inverter is widely used in the wireless power transmission (WPT) system due to its high efficiency. Generally, its switching frequency should be in accordance with the resonant frequency. In a weak-coupling case, the maintenance of high transmission efficiency requires a higher resonant frequency, which would restrict its application due to the corresponding high switching frequency. To solve

This article presents a 1024-element dual-polarized Ku-band (10.7–12.7 GHz) satellite communication (SATCOM) receive (RX) phased array. The array consists of four 16 $\times16$ subarray tiles, each of which comprises 64 eight-channel beamformer chips, 256 dual-channel low-noise amplifiers (LNAs), and 256 dual-polarized antennas built on an affordable printed circuit board (PCB). The antennas spaced

A low-power 2.2–2.4-GHz receiver front end for Internet-of-Things (IoT) applications is presented. The front end consists of a capacitively cross-coupled common-gate low-noise amplifier (CC-CGLNA), with translational positive feedback from baseband to RF through a four-phase switching mixer, providing RF filtering and matching, in conjunction with a 1:4 transformer. A detailed analysis of the architecture

We describe efficient four-coil inductive power transfer (IPT) systems that operate at 100 MHz. The magnetically coupled transmitter and receiver were made from electrically small and high- ${Q}$ loop-gap resonators (LGRs). In contrast to the commonly used helical and spiral resonators, the LGR design has the distinct advantage that electric fields are strongly confined to the capacitive gap of the

This article proposes a dual-band complementary metal–oxide–semiconductor (CMOS) radio frequency (RF) front end employing a hybrid transformer-based electrical-balance duplexer (EBD) and $N$ -path filter embedded low-noise amplifier (LNA) for both in-band full duplexing (IBFD) and frequency-division duplexing (FDD) radios. To securely obtain sufficient self-interference cancellation (SIC) or transmitter

Two 16-element radio frequency (RF) transceiver antisymmetric coil arrays with two different implementation designs aiming for improved characteristics for static phase $B_{1}^{+}$ shimming and parallel receive were developed for human cardiac MRI at 7 T. Both cardiac arrays consist of a weakly curved lightweight housing fit to an average human thorax shape as an anterior array in combination with

This article describes a 5.8-GHz band highly efficient 1-W rectenna that consists of a bridge diode, directly connected to a short-stub-connected high-impedance dipole antenna, with a designed antenna resistance of $580~\Omega $ . The proposed antenna topology realizes circuit functionalities of impedance transform, impedance matching, harmonic reaction, and dc blocking while maintaining a high antenna

This Mini-Special Issue of the IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES (TMTT) is comprised of expanded articles from the 2020 IEEE Radio Frequency Integrated Circuits Symposium (IEEE RFIC), held virtually on August 4–6, 2020, in response to the worldwide COVID-19 pandemic. First, we are grateful to the organizers of the symposium, including the steering and the technical committees, as

This article presents a power efficient 24–28-GHz four-element phased-array transceiver (TRX) front end (FE) for 5-G base stations and user equipment communications. A power efficient hybrid quadrature vector interpolation-based phase-shifting architecture is proposed to increase the TX and RX power efficiency and phase resolution. A transformer-based embedded T/R switch is proposed which minimizes

This article presents a fully integrated Fourier-domain digital-to-analog converter-based transmitter (Tx). The proposed topology generates a coherent bandwidth (BW) of up to 2 GHz by exploiting the relationship between the discrete and the continuous-time Fourier transform. Thus, the digital-to-analog converter (DAC) sampling rate and the entire digital signal processing (DSP) speed are reduced by

This article describes a single-pole, single-throw (SPST) CMOS switch aimed at integrated transceiver applications. The SPST switch realizes better than 50-dB isolation (ISO) across dc-to-43 GHz while maintaining an insertion loss (IL) below 3 dB. To maximize ISO, substrate coupling is compensated using bilateral RF signal cancellation in a fully differential circuit topology. Measured RF input power

This article presents an implantable low-power wireless integrated system for tactile sensing applications. The reported application-specified integrated circuit (ASIC) uses a low-loss magnetic human body communication channel for both wireless power and data transfer. The chip is hybrid-integrated with an in-house fabricated MEMS capacitive force sensor to form an implantable artificial mechanoreceptor

This article presents an ultralow-power 60-GHz indoor frequency-modulated continuous-wave (FMCW) radar in 28-nm CMOS. The radar front end employs a tunable matching network (TMN), which tracks the chirp frequency and supports a 17% fractional bandwidth, covering unlicensed 60-GHz bands (57–66 GHz). A frequency sixtupler chain (x6) in the transmitter (TX) provides an output power of 8.1 dBm while achieving

Emerging 5G millimeter-wave (mm-wave) networks use electronic beamforming and beamsteering and support signal bandwidths on the order of hundreds of MHz. Given these characteristics, opportunities exist to develop 3-D sensing applications that leverage 5G mm-wave communications infrastructure. In this context, this work introduces a signal processing pipeline that can: 1) accurately extract the Time

A coupled-field volume integral equation (CFVIE) method is developed for the calculation of the normalized cutoff wavenumbers of circular metallic walled waveguides having concentric continuously varying highly inhomogeneous gyrotropic (i.e., gyroelectric and gyromagnetic) infill. The normalized cutoff wavenumbers are obtained as the roots of a determinantal equation formed by solving the CFVIEs using

In this article, a nonlinear capacitance model for a large-signal compact model of partially depleted (PD) silicon-on-insulator (SOI) transistors is proposed. When the transistors are operated in the saturation and triode region, the gate–source capacitance ( $C_{\mathrm {gs}}$ ) and the gate–drain capacitance ( $C_{\mathrm {gd}}$ ) change with the gate–source voltage ( $V_{\mathrm {GS}}$ ) nonlinearly

The method of auxiliary sources (MAS) is one of the numerical methods employed for the determination of the cutoff wavenumbers (eigenvalues) of cylindrical waveguides. According to the general scheme of MAS, the eigenvalues are obtained by requiring the square impedance matrix to be singular and therefore its determinant to be zero (or its condition number to be large). For large matrices, such computations

In this article, a ridged substrate integrated coaxial line (RSICL) is proposed, which has a compact size, wide bandwidth, and excellent shielding. The RSICL has two ridges set on both sides of its outer conductor, which introduce additional capacitance and enhance shielding performance. Compared with the SICL, the width of the RSICL can be reduced significantly for 50- $\Omega $ characteristic impedance

This article describes the design methodology to achieve reflective diode-based parametric frequency-selective limiters (pFSLs) with low-power thresholds ( $P_{\mathrm{ th}}$ ) and sub-dB insertion-loss values (IL s.s ) for driving power levels ( $P_{\mathrm{ in}}$ ) lower than $P_{\mathrm{ th}}$ . In addition, we present the measured performance of a reflective pFSL designed through the discussed

In this article, a novel configurable microwave passive component is presented, which can be programmed into multiple functions according to the design requirement. The proposed configurable microwave passive component is realized with a 2-D bridged-T coil array, which can be programmed through different wire-bonding configurations to achieve the desired functions. As a design example, a compact configurable

This article presents novel wideband fully differential hybrid and rat-race couplers whose design methodologies are based on the multimode star junction. The couplers benefit from the even and odd modes of the slotted-microstrip sections that constitute the junction to realize compact equivalent transmission lines, while they exploit the characteristics of the slotline to achieve differential ports

In this article, a broadband $W$ -band $\mathrm{TE}^{\square }_{10}$ – $\mathrm{TE}^{\bigcirc }_{02}$ mode converter is proposed and verified. To improve the output performance of the $\mathrm{TE}^{\square }_{10}$ – $\mathrm{TE}^{\bigcirc }_{02}$ mode converter, a $\mathrm{TE}^{\square }_{10}$ -to- $\mathrm{TE}^{\square }_{40}$ intermediate mode conversion section with a Y-type power divider structure

The design of a patented broadwall waveguide hybrid coupler, derived from the working principle of a septum polarizer, is presented. This $E$ -plane coupler requires a single and large aperture in the common broadwall of the two parallel waveguide transmission lines to function, facilitating its manufacturing and assembly. The working principle of this hybrid coupler is detailed, supported by equations

Novel cross-coupled dual-band bandpass filters (BPFs) with compact size are proposed based on dual-mode isosceles right-angled triangular (IRAT) resonators. The dominant mode in the IRAT resonator is the TM 100 Z mode. By introducing posts in the resonators, an LC resonant unit is formed, which resonates at a lower frequency than the TM 100 Z mode. In the design of novel dual-band filters, the LC mode

This article presents a novel class of dual-mode substrate-integrated waveguide (SIW) bandpass filters exploiting perturbed SIW rectangular cavities. By introducing metallized via-holes along the central line of an SIW rectangular cavity, the resonant frequency of TE 101 mode can be shifted close to that of TE 201 mode, thus creating a dual-mode resonator. This structure implements a doublet, which

In this article, we present a new generic reflectionless filter topology that can be used in designing not only a filter having zero reflection at one port but also a filter having zero reflection at both ports. Detailed mathematical analysis of the presented reflectionless filter topology is provided. The three unique features, which will be described throughout this article, allow us to straightforwardly

This article presents two types of planar/waveguide quasi-elliptic linear-phase filters using mixed cascade frequency-dependent triplets (FDTs) and extracted pole sections (EPSs). Specifically, we propose the circuit synthesis and planar/waveguide realization techniques for quasi-elliptic linear-phase filters using the cascaded FDT and EPS. The circuit synthesis for the proposed filters avoids the

In this article, a series of filtering cavity slot arrays using high-order modes are investigated. It is found that each unit of the cavity slot arrays in the proposed high-order mode resonator is in phase with the same amplitude, which helps enhance the antenna gain and reduce the sidelobe level. Meanwhile, the filtering function is integrated into the design for frequency selectivity and harmonic

This article presents a generalized theory and new design methodology for reverse-load-modulated dual-branch (RMDB) power amplifiers (PAs), which uses a current-biased transistor in the main branch to realize optimal load modulation without using the impedance transformers at the output of the PAs. Consequently, this topology offers a proper load modulation mechanism over a wider frequency bandwidth

This article presents a fully integrated distributed efficient power amplifier (DEPA) for fifth-generation (5G) massive multiple-input multiple-output (MIMO) applications. In conventional DEPA, an individual input matching network (IMN), power splitter, and phase compensation line are used for each auxiliary power amplifier (PA) unit, resulting in a large overall size. To facilitate integration, an

This article presents a fully differential high-dynamic-range direct-conversion receiver for sub-1-GHz band applications in a 180-nm CMOS technology. The integrated self-adaptive multipart automatic gain control (AGC) loops are designed to cope with large input signal. In the radio frequency (RF) domain, a gain-adjustable noise-canceling balun low-noise amplifier (LNA) and a high-linearity RF variable

This article proposes a new and compact symmetrical Doherty power amplifier (DPA) configuration that provides extended output-back-off (OBO) and enhanced load modulation. The concept of active harmonic control (AHC) is introduced to remedy the reduced-conduction-angle operation of the class-C auxiliary device, providing enhanced auxiliary current and power capability. Semianalytical study based on

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.

Sensitivity analysis is important for electromagnetic (EM)-based design. The existing adjoint EM sensitivity analysis methods have to solve large systems of EM equations repetitively for different frequencies. This article addresses this situation and proposes to speed up the EM sensitivity analysis over a frequency range by solving EM equations at only a single frequency. A new adjoint EM sensitivity

An elegant and convenient rigorous approach for solving canonical circular open-ended dielectric-loaded waveguide diffraction problems is presented. It uses the solution of corresponding Wiener–Hopf–Fock equation and leads to an infinite linear system for reflection coefficients (S-parameters) of the waveguide, and the latter can be efficiently solved numerically using the reducing technique. As a

The derivation of the Kramers–Kronig relations is revisited based on system theory considerations to show their general validity and to emphasize how these relations are connected to the causality of a linear system. Then, the closed form Kramers–Kronig and subtractive Kramers–Kronig relations are introduced based on shape-preserving third-order piecewise cubic interpolation. The advantage of this

A novel low-loss suspended-line gap waveguide (SLGW) supporting transverse electromagnetic (TEM) propagation is presented for millimeter-wave applications for the first time. The suspended line is composed of two parallel strips connected by metal via holes. Periodic stacked-mushroom electromagnetic band gap (SM-EBG) structures are used to package the suspended line by creating a stopband for all parallel-plate

In this article, a novel filtering crossover with independently tuned channel passbands and reconfigurable filtering power divider (PD) function based on evanescent-mode cavity (EVA) is proposed for the first time. It consists of four substrate-integrated-waveguide (SIW) EVA resonators loaded with piezoelectric actuators for frequency tuning. Four sets of varactors are used between adjacent resonators

Space mapping is a recognized surrogate-based optimization method to accelerate the electromagnetic (EM) design. In this article, for the first time, space mapping is elevated from solving the problem of EM optimization to solving the problem of multiphysics optimization for high power microwave filters. Multiphysics analysis, which involves the EM domain with other physics domains, is increasingly

A K-/Ka-band distributed attenuator in a 28-nm CMOS process is presented for a phased array. The proposed voltage-controlled distributed attenuator is designed using nonuniform varistors for a wide attenuation range with a compact size. An attenuation range of 25 dB was achieved with only three sections, which are 90° apart. The phase imbalance of the proposed attenuator is minimized using an artificial

In this article, a method for design automation high-efficiency power amplifiers (PAs) based on an optimization-oriented is proposed. The advantages of using particle swarm optimization to design PAs in electronic design automatic tools are analyzed, and then, simulated annealing is combined to form simulated annealing particle swarm optimization (SA-PSO). In this article, the perfectly inelastic collision

In this article, a continuous-mode inverse class GF (CCGF −1 ) power amplifier is introduced based on a new closed-form expression for the drain current. This analytical expression is utilized to exploit second source harmonic impedance manipulation in order to expand the design space of the output matching circuit resistively. This approach allows to diminish the complexity of the design of the load