We propose to realize ultra-wideband polarization conversion metasurfaces in microwave regime through multiple plasmon resonances. An metasurface is designed using a double-head arrow structure and further demonstrated both numerically experimentally. Four resonances are generated by electric magnetic resonances, which lead bandwidth expansion of cross-polarization reflection. The simulated results show that the maximum efficiency nearly 100% at four resonance frequencies 1:4 3 dB can be...

Phase gradient metasurface (PGMs) are artificial surfaces that can provide pre-defined in-plane wave-vectors to manipulate the directions of refracted/reflected waves. In this Letter, we propose achieve wideband radar cross section (RCS) reduction using two-dimensional (2D) PGMs. A 2D PGM was designed a square combination 49 split-ring sub-unit cells. The additional along two simultaneously, leading either surface wave conversion, deflected reflection, or diffuse reflection. Both simulation...

In this paper, we propose to achieve wideband linear-to-circular (LTC) polarization conversion by ultra-thin bi-layered metasurfaces. As an example, LTC metasurface operating in 11.4–14.3 GHz is designed and fabricated, which composed of two layers metallic pattern arrays separated a 1.5 mm-thick dielectric spacer. When linearly polarized waves impinge on the metasurface, transmission greater than 90% over wide frequency range from 11.0 18.3 GHz. Meanwhile, axis ratio lower 3 dB 9.8–18.3...

This paper proposes a dual-band eight-antenna array for multiple-input and multiple-output (MIMO) applications in 5G mobile terminals. The designed MIMO antenna comprises eight L-shaped slot antennas based on stepped impedance resonators (SIRs). required dual-resonance can be obtained by adjusting the ratio of SIR, good matching ensured each element tuning position microstrip feed line. experimental results show that measured return loss higher than 10 dB inter-element isolation greater 11.2...

A class of millimeter-wave E-plane waveguide bandpass filters (BPFs) based on spoof surface plasmon polaritons (SSPPs) have been presented in this article. Three kinds SSPPs, with different patterns coated the dielectric substrate, are inserted into WR-10 standard rectangular for design BPFs. To clarify filtering characteristics proposed BPFs, dispersive properties SSPP unit cells investigated and discussed. The electromagnetic simulation results demonstrate that bandwidths center...

Gradient metasurfaces (GMs) can provide pre-defined wave vectors that are along the surface of GMs. When additional vector is greater than incident waves, waves be coupled efficiently as spoof plasmon polaritons (SPPs) even under normal incidence. In this Letter, design SPP couplers was proposed based on A high-efficiency coupler designed using split-ring resonators. Both simulation and experiment show GM achieve nearly perfect SPP-coupling incidence at frequency.

Even though ghost imaging (GI), an unconventional method, has received increased attention by researchers during the last decades, speed is still not satisfactory. Once data-acquisition method and system parameters are determined, only processing potential to accelerate image-processing significantly. However, both basic correlation compressed sensing algorithm, which often used for imaging, have their own problems. To overcome these challenges, a novel deep learning proposed in this paper....

We numerically demonstrate a tunable dual-band terahertz metamaterial absorber (MA) with near-unity absorption using single-layer square graphene ring structure T-shaped strips. By periodically loading four strips to the periodic array without additionally increasing size of MA device, pre-existing resonant frequency will have red shift and simultaneously new resonance be generated at higher for achieving MA. The two peaks can tuned frequencies interest by varying parameters operating...

This paper proposes a reconfigurable polarization converter based on p-i-n diode controlled active metasurface (AMS). The AMS consists of thin dielectric substrate and is tuned by two identical layers elliptic split rings loaded with diodes. diodes are positioned between the gaps biased through interconnected without extra bias network. design achieves conversion from linear to circular when OFF, whereas no takes place ON. A prototype proposed fabricated, operational characteristics...

A bilayered chiral metamaterial is proposed to realize a dual band polarization angle insensitive 90° rotator. The unit cell of the composed by twisted electric field coupled resonators in four-fold rotation symmetry. simulation and measured results show that this device can work with an extremely low loss conversion ratio more than 99%. study current fields distribution indicates cross-polarization transmission due both coupling magnetic coupling.

A gradient metasurface is proposed to obtain both surface wave coupling and anomalous reflection. The unit cell of the composed by six electric field coupled resonators in different rotation angle, which provides a phase gradient. simulation measured results show that this can work at 7.8 GHz as coupler 10.288 providing phenomenon At two frequencies, direction reflection polarization-controlled, efficiencies are polarization-invariant. left-handed polarization incidence, opposite situation...

We propose a broadband perfect polarization conversion metasurface composed of copper sheet-backed asymmetric double spilt ring resonator (DSRR). The convertibility results from metallic ground and multiple plasmon resonances the DSRR. Physics are governed by electric magnetic resonances. Both simulation measured show that ratio (PCR) is higher than 99% for both x- y-polarized normally incident EM waves fractional bandwidth about 34.5%. possesses merits high PCR broad bandwidth, thus has...

This paper presents a three-dimensional microwave metamaterial absorber based on the stand-up resistive film patch array. The has wideband absorption, lightweight, and polarization-independent properties. Our design comes from array of unidirectional patches backed by metallic plane, which can excite multiple standing wave modes. By rolling as square enclosure, we obtain property. Due to modes, most incident energy is dissipated patches, thus, ultra-wideband absorption be achieved...

In this letter, a novel bandpass frequency selective surface (FSS) with miniaturized periodic element is presented. The proposed FSS printed on one face of single-layer substrate relative permittivity 2.65. has promising miniaturization characteristics the unit-cell dimension 0.058λ×0.058λ, where λ represents free-space wavelength corresponding to resonant frequency. exhibits excellent stability under different polarizations and incident angles. Both simulation measurement results validate...

In this paper, we report on the design, fabrication and subsequent investigation of a broad band cross polarization converter based C2-symmetric ring/disk cavity. Different plasmon hybridization modes are excited in cavity enable manipulations. The designed can convert x or y polarized incident wave to its frequency range from 9.65 14.16 GHz with bandwidth ~38% central wavelength an efficiency higher than 80%. At 9.25 14.35 GHz, (y) is converted left (right) handed right (left) circularly...

In this letter, a reflective metasurface composed of double-layer metallic L-patterns is designed. Both the simulated and measured results demonstrate that when incident angle ranges from 0° to 30°, can be regarded as three-band polarization converter. On one hand, convert TM (TE) polarized wave into right (left)-handed circularly 9.1 16.5 GHz well left (right)-handed 20.0 25.4 GHz. other realize cross-polarization conversion between TE waves 17.4 18.9 addition, transmission model expanded...

A compact dual-polarized antenna with total dimensions of 31 × 14 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> is proposed for the fifth-generation base stations at 3.5 GHz. The consists two orthogonal bow-tie dipoles. bandwidth enhanced using eight parasitic strips along dipole patches, U-shaped slots around feeding positions, and dielectric cavity, which brings resonant frequencies closer to each other. isolation between dual...

In this letter, a miniaturized dual-band frequency selective surfaces with second-order band-pass response at each operation band is presented. The design implemented by cascading two-dimensional periodic array of double square loops and an wire grids. proposed structure composed three metal two dielectric layers acts as spatial dual microwave filter large separation. predicted FSS has the merits broadband response, excellent stability for different incident angles, sharp roll-off X-...

In this letter, an active metasurface for vortex beam generation is proposed. This can transform the incident plane wave into beams carrying orbital angular momentum of three different orders. composed array varactor diodes loaded unit cells. The transmission phase each cell be fully controlled by capacitance diodes. Different modes separately generated simply changing distribution on aperture. properties proposed are demonstrated simulation and measurement results, which have a good...

Baffles loaded by split-ring resonator (SRR) are proposed to reduce the mutual coupling for ±45° dual-polarized multiple-input-multiple-output (MIMO) antenna. Each baffle consists of two rectangular SRR printed on one side a 1 mm FR4 substrate. The final decoupling structure contains four baffles forming barrier wall that reduces over 5G band 3.4-3.8 GHz. Dual-polarized cross-dipole array with loading is simulated and measured demonstrate their effectiveness in reduction. results show can be...

The mismatches of signal and array geometry will seriously degrade the performance adaptive beamformer. In this paper, we propose two methods for robust beamforming based on conjugate gradient (CG) algorithm. proposed beamformers offer a significant improvement in computational complexity while providing same best at present. first method belongs to diagonal loading technique. We derive CGLS algorithm (CG applied normal equations) simple choose level coarse estimation desired power. This...

In this paper, a miniaturized gain-enhanced antipodal Vivaldi antenna (AVA) with gradual corrugated edges (GCEs) and triangular metal directors (MDs) is investigated. Its operating frequency band extended the gain improved at lower frequencies due to use of GCEs. addition, E-plane beam tilt has been removed improvements on side-lobe level are achieved. By applying MDs two surfaces radiation aperture AVA, its higher improved. Therefore, variation tends be flat within whole band. Furthermore,...

The reverberation chamber (RC) has traditionally been used for electromagnetic compatibility tests. About two decade ago, it found application in various over-the-air (OTA) tests of antennas and wireless devices. This paper gives an overview nearly decades research on the RC-based OTA tests, ranging from antenna measurements characterizations to both terminals base stations. Apart advantages some important issues are identified.

In this letter, a GaAs-based wideband spoof surface plasmon polariton (SSPP) waveguide with super compact size is presented at millimeter-wave regime. The periodic SSPP unit cell consists of longitudinal slot and meander in transversal direction, its corresponding has good low-pass filtering feature. momentum microstrip line for measurement feeding to the SSPPs can be well matched without any gradient transition structures. To apply into design bandpass filter (BPF), row vias added certain...