Shengying Liu

A simple dual wideband shared-aperture antenna array with wide 2D angle scanning is proposed in this paper. One printed dipole antenna element operating in X-band and four microstrip Quasi-Yagi antenna elements operating in Ku-band are combined to construct a shared-aperture super cell for the phased array. Gaps are cut on the substrate to reduce the mutual coupling between the adjacent elements. Both the X-band and Ku-band elements are printed on one-layer substrate to realize dual wide bands with the same polarization, meanwhile exhibiting a simple structure. A large array topology composed of 14×12 X-band units and 16×16 Ku-band units is fabricated for verification. Measured results show that the proposed antenna array has wide bandwidths of 11.8% in X-band and 25% in Ku-band, meanwhile it has a relatively wide scanning angle ranging from -60° to +60° with the gain decrease less than 5.1 dB

In this paper, a wide-angle linearly scanning leaky-wave antenna (LWA) based on spoof surface plasmon polaritons (SSPPs) with a very high scanning rate is proposed. A sine curve period is introduced to construct the SSPPs transmission line in the form of a sine curve, which can transform the dispersion curve to the fast wave region to realize the desired dispersion properties for linearly high scanning rate LWA. The simulated results show that the proposed LWA achieves a scanning angle range of 109over a narrow operation bandwidth of 7.73–8.13 GHz, implying high linearity, and a high scanning rate. A prototype is fabricated and measured, indicating that the measured scanning angle range is 100within the frequency band of 7.82–8.21 GHz, and the relative average scanning rate (RASR) is 2053.4. Compared with ideal linear scanning in the operating frequency band, the mean absolute value error (MAVE) of the measured scanning angle-frequency curve is 1.032, which validates the proposed design with good agreement between the simulated and measured results. The high scanning rate and scanning linearity performances of the LWAs exhibit great value in reducing both the occupation of electromagnetic spectrum resources and the requirements of accuracy for transmitters and receivers, respectively.

A Ku-band variable inclination continuous transverse stub (VICTS) antenna system for vehicle-to-satellite communication is designed with high gain and low sidelobe level (SLL). Taylor distribution is used to determine the radiation power for each slot by extracting the admittance of each slot to achieve a low SLL. The antenna system contains the VICTS antenna and the servo control system. The servo control system is used to rotate the feeding and radiating plates of the VICTS antenna to realize beam steering. The feeding plate is placed underneath the radiating plate for a compact size. For verifying the concept, the antenna system is prototyped and measured. The measured results show that within 13.75-14.5 GHz, the voltage standing wave ratio (VSWR) is below 1.4. A large beam scanning range of 7° ~ 64° or −7° − −64° in elevation and 360. in azimuth is achieved, with a maximum gain of 32.1 dBi. For all the scanning angles, the SLLs maintain lower than −16.5 dB.

Metasurfaces enable a new degree of controlling electromagnetic (EM) wave by modulating subwavelength artificial structures. In this article, a reflection-type metasurface based on the modified Pancharatnam-Berry (P-B) phase elements is proposed to manipulate the reflected EM wave under oblique incidence. Based on the modified P-B phase, the desired linear phase gradient along the x-axis can be achieved at the interface of the metasurface by adjusting the rotation angle of the unit cells. When a circularly polarized EM wave illuminates on the metasurface obliquely, the anomalous reflected wave can be observed in a broad bandwidth with high efficiency, and the reflection angle can be predicted by the generalized snell's law. Two metasurfaces with different phase gradients are designed in this article. The simulated results agree well with the theoretical designs, showing outstanding ability to manipulate the propagation of the EM wave. With specific phase gradient of the proposed metasurface, the anomalous reflected wave can be bent to the same side of the normal with the incident wave, which means that negative reflection effect can be achieved. Our design provides a solution to manipulate reflected beam under oblique incidence with high conversion efficiency, which has great practical applications in medical imaging, communication technology, and energy harvesting.

Huygens metasurface, composed of electric and magnetic dipoles, can fully control the transmission and reflection coefficient in theory. In this paper, a multi-phase hologram utilizing Huygens metasurface is presented in microwave regime. Here, we focus on the achievement of holographic rotation around the origin of Cartesian coordinates and the center of images individually. The spatial rotation operations are realized with calculated phase distribution based on time-shifting operations and rotational invariance of Fourier transform. Our designs expand the route to realize more powerful manipulations of electromagnetic (EM) wave propagation for flexible and continuous control of holographic images.

In this paper, a novel broadband printed folded dipole RFID tag antenna with the artificial magnetic conductor (AMC) ground plane in UHF band is proposed. By introducing AMC ground plane, the RFID tag antenna shows great performance on the metal surface. The bandwidth of the proposed antenna ranges from 0.81GHz to 0.93GHz, which can cover both the China standard (840-845 MHz) and the FCC standard (902-928 MHz). The gain of the antenna is 2.18dB, and it is improved about 0.6 dB compared with the design without the AMC ground plane. We believe that the proposed antenna provides a valuable reference for RFID tag antenna design mounted on metal environment, and it can be widely used in UHF RFID system.