In this letter, a high-gain, aperture-efficient cavity resonator antenna using metamaterial superstrate is reported. Highly reflective compact surface resonating at 10.15 GHz with measured 3-dB bandwidth stopband characteristic of 4.10 from 8.1 to 12.2 proposed. Material property the metasurface studied by free-space technique. Next, used as patch operating 10.09 GHz, forming Fabry–Perot cavity. Gain enhancement 11.85 dB in H-plane and 12.5 E-plane improved cross-polarization level...

This letter presents a highly isolated compact four-element planar ultrawideband (UWB) multiple-input-multiple-output (MIMO) antenna array configuration. The main advantages of the proposed configuration are that it requires no isolation/decoupling circuit and is easily extendable to larger size array. consists novel miniaturized slotted annular ring monopole each element in placed orthogonal its adjacent elements. fabricated structure provides good impedance bandwidth matching high...

In this letter, frequency selective surface (FSS) properties of a uniplanar electromagnetic band-gap (EBG) unit cell are studied. The consists meander-line inductor and interdigital capacitors on one side substrate. Simulation results indicate that the exhibits passband characteristics centered at 10.04 GHz. FSS property structure is verified by measurement using X-band waveguides. measured show 9.45 A 13 × array these cells (FSS screen) used as superstrate distance ≈ 0.5λ <sub...

This paper describes a dual-band electromagnetic (EM) absorber for <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">C</i> - and xmlns:xlink="http://www.w3.org/1999/xlink">X</i> -band applications. The proposed structure consists of two circular ring resonators that are modified to make the compact. is demonstrated be conformal, insensitive polarization angle oblique incidence incoming EM wave. To authors’ knowledge, it thinnest reported with...

This paper proposes a hybrid decoupling method based on novel electromagnetic bandgap (EBG) structure and hair-pin shaped defected ground (DGS) to obtain high isolation between 2-element multiple input output (MIMO) antenna at 5G millimeter wave band over 27.5–28.35 GHz. The proposed EBG designed stacked dielectric substrates, achieves wide frequency band-gap 26.2–32.03 GHz (20 %). A 2 × 3 array of the is arranged two electromagnetically coupled radiating patches in order suppress surface...

This work presents a broadband linear–cross polarizer for K- and Ka-band applications. The design consists of simple asymmetric width-based meander-line metasurface printed on thin FR-4 grounded dielectric substrate. Normal incidence demonstrates 90% polarization conversion ratio (PCR) bandwidth (BW) 20.64 GHz from 18.31 to 38.95 with 72.1% fractional BW (FBW). Due the destructive interference involved at greater oblique angles, reflective polarizers experience severe degradation PCR...

A polarization-insensitive dual-band artificial magnetic conductor (AMC) structure is designed and experimentally verified. It consists of a planar array annular ring-slot loaded rectangular patches. Details the proposed origin two bands discussed. Through simulations measurements, it shown that insensitive to polarization incident wave. The tuning higher AMC band demonstrated by varying capacitance slot through its width variation. used as reflector for wideband monopole patch antenna. at...

This paper presents a beam steerable low-profile lens antenna with flat top wide and high gain operating at 10.10 GHz. It consists of graded index metasurface (GIMS) placed on the microstrip patch (MPA) radiator. An ultrathin linear (LGIMS) radial (RGIMS) were designed for magnitude phase transformation radiated from microwave First, an LGIMS was by placing MPA radiator optimum height. A maximum measured 16.37 dBi indicating enhancement 11.50 dB steering in conical plane vertex angle 84°...

In this article, a compact dual-band linear-tocircular polarization converter designed on single-layer substrate is proposed. The unit cell of the has size 3.72 × 3.90 1.52 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> (0.0072λ <sub xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> , λo calculated with respect to 20.67 GHz). consists split rings and pair metallic strips printed both sides for operation. proposed measured 3-dB axial...

In this article, a closed ring resonator-based absorber with eleven consecutive absorption peaks is proposed over <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">X</i> and xmlns:xlink="http://www.w3.org/1999/xlink">K</i> bands an average rate of 96.29%. The design consists circular resonators embedded in the circularly slotted square patch printed on top grounded FR-4 substrate. surface current distributions well illustrates reason behind...

This communication presents the miniaturized low-profile second-order (SO) bandstop frequency selective surfaces (FSSs) for single- and dual-band resonances. The unit cell comprises two identical first-order (FO) elements in a back-to-back configuration with metal grid between. Two thin dielectric substrates separate three layers. proposed FO consists of intercell-connected spiral resonators (SRs) capacitively coupled cross loop dipole. SO filter response FSS exhibits wide stopband (...

This paper presents a unified analytical approach to solve class of shielded strip and microstrip-like transmission lines with multilayer dielectrics under TEM-wave approximation. The analysis makes use the variational technique in space domain combined "transverse line" method. Expressions are derived for capacitance single line, coupled two-line four-line structures. same formulas can be used such structures by substitution parameter, namely, admittance at charge plane, which obtained...

This work presents a Ku-band microelectromechanical systems (MEMS) based 5-bit phase shifter using dc contact single-pole-four-throw (SP4T) and single-pole-double-throw switches. The design is implemented coplanar waveguide transmission line. Two individual 2-bit shifters one 1-bit are cascaded to develop the complete shifter. fabricated on 635- μm alumina substrate surface micromachining process. demonstrates an average insertion loss of 2.65 dB in 13-18-GHz band with return better than 22...

This paper proposes a design scheme of concurrent dual-band Doherty power amplifier (DPA) which can be reconfigured to two different pairs dual bands for multiband and carrier aggregation applications. In addition the reconfiguration frequencies operation, output back-off (OPBO) region efficiency enhancement also in this DPA. As proof concept, reconfigurable DPA is designed operate at 1500 2140 MHz first band, whereas on it will concurrently 1850 2350 MHz. While operating has an enhanced up...

In this work, broadband linear to cross and circular polarization converter for K Ka-band applications is proposed. The metasurface comprises a novel H-shaped unit cell printed on 1.2 mm thin FR-4 grounded dielectric substrate. It exhibits 90% conversion ratio (PCR) over bandwidth of 22.26 GHz (17.97-40.23 GHz) with 76.5% FBW maintaining minimal PCR 92.5%. also maintains handedness circularly polarized incident wave. Surface current distributions at different resonant frequencies are...

This article presents a design strategy to improve the bandwidth of three-stage Doherty Power Amplifier (DPA) by controlling phase difference between dual RF inputs digitally. The theory also proposes multiple back-off reconfigurability without using tuning elements and extra circuitry. proposed is validated demonstration dual-input DPA which designed implemented Wolfspeed's GaN HEMT transistors. measured results show drain efficiency 50.4 - 58% 46.1 65.4% at 12 dB 6 respectively, over...

A dual-band rectifier is presented for RF energy harvesting (RFEH) and microwave power transfer (MPT) applications. Starting with a single-band rectifier, the second band added by utilizing half-wavelength transmission line (HWTL) in matching network (MN). series diode topology using HSMS-2860 Schottky used conversion. The simultaneously harvests conversion efficiency (PCE) of 54.9% 42.3% output voltage 1.4 1.242 V at 0-dBm input 3.5-GHz 5G 5.8-GHz Wi-Fi band, respectively.

In this article, a novel design of compact frequency-selective rasorber exhibiting absorption–transmission–absorption characteristics and having high passband selectivity has been proposed. A square-loop resonator with mounted lossy elements serves as the elemental broadband absorber from 4 to 12 GHz. The transmission frequency at 8.4 GHz is realized by printing Minkowski fractal-shaped high-Q factor on resistive layer, which provides pole corresponding double-cross-slot-shaped bandpass...

A three-element quasi Yagi-Uda antenna array with printed metamaterial surface generated from the of uniplanar capacitively loaded loop (CLL) unit-cells on substrate operating in band 25-30 GHz is proposed. The configured to provide a high-refractive index tilt electromagnetic (EM) beam two dipole antennas placed opposite each other. region focuses rays and hence increases gain individual by about 5 dBi. elements are 10 mil center separation 0.5 λ 0 at 28 GHz. covers measured return loss dB...