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beam steering correction of the quarter wave resonator in the HISCL

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Chinese Physics C 2014年第10期38卷 107-110页

作者：刘淑会王志军张聪何源 Insititution of Modern Physics the Chinese Academy of Sciences

The Intensity Heavy Ion Superconducting Linear Accelerator as the injector of the High Intensity Heavy- Ion Accelerator Facility, which is a new project proposed in China has been designed. One of the design options in the low energy part is based on Quarter Wave Resonators （QWRs）. However, because of the unsymmetrical geometry of the cavity, there are dipole fields near the beam hole, which may steer the beam vertically, thus leading to emittance growth and beam loss. The effect of the dipole mode field is analyzed, and a method to overcome the beam steering effect by placing QWRs with opposite orientation is proposed in this paper. The simulation results show that the beam steering effect is reduced effectively by this method, and the deviation of the beam centroid is decreased from 2.87 mm to 0.1 mm. The emittance growth is also smaller.

关键词： QWR lattice structural layout beam steering

Ultra-thin two-dimensional transmissive anisotropic metasurfaces for polarization filter and beam steering application

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Chinese Physics B 2016年第10期25卷 132-138页

作者：郭文龙王光明李海鹏张昆蔡通 Air and Missile Defense College Air Force Engineering University

We propose an anisotropic planar transmitting metasurface, which has the ability to manipulate orthogonally-polarized electromagnetic waves in the reflection and refraction modes respectively. The metasurface is composed of four layered rectangular patches spaced by three layered dielectric isolators each with a thickness of 0.15λ0 at 15 GHz. By tailoring the sizes of the patches, the metasurface functions as a band-stop filter for the y-polarzied wave and a band-pass filter for the x-polarized wave operating from 14 GHz to 16 GHz. Moreover the phases of the transmitting x-polarized wave can be modulated at about 15 GHz, which contributes to beam steering according to the general refraction law. Experimental results are in good accordance with the simulated ones, in which the reflection efficiency is almost 100% while the transmission efficiency of the x-polarized wave reaches 80% at 15 GHz. Besides, the transmitted x-polarized wave is effectively manipulated from 14 GHz to 16 GHz.

关键词： metasurface beam steering polarization beam splitter

Programmable agile beam steering based on a liquid crystal prism

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Chinese Physics B 2011年第11期20卷 317-322页

作者：徐林黄子强杨若夫 School of Optoelectronic Information University of Electronic Science and Technology of China

To meet the application need for agile precision beam steering, a novel liquid crystal prism device with a simple structure, convenient control, low cost and applicable performance is presented, and analysed theoretically and experimentally. The relationships between the optical path and the thickness of the liquid crystal cell under different voltages are investigated quantitatively by using a theoretical model. Analysis results show that the optical path profile of the liquid crystal prism has a quasi-linear slope and the standard deviation of the linear slope is less than 16 nm. The slope ratio can be changed by a voltage, which achieves the programmable beam steering and control. Practical liquid crystal prism devices are fabricated. Their deflection angles and wavefront profiles with different voltages are experimentally tested. The results are in good agreement with the simulated results. The results imply that the agile beam steering in a scope of 100μrad with a micro-rad resolution is substantiated in the device. The two-dimensional beam steering is also achieved by cascading two liquid crystal prism devices.

关键词： liquid crystal polarization devices beam steering optical scanner

Broadband beam steering for misaligned multi-mode OAM communication systems

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Journal of Systems Engineering and Electronics 2021年第4期32卷 779-788页

作者： TIAN Zhengjuan CHEN Rui LONG Wenxuan ZHOU Hong MORETTI Marco School of Communication Engineering Xidian UniversityXi’an 710071China Department of Information Engineering University of PisaPisa 56126Italy

Orbital angular momentum(OAM)at radio frequency(RF)has attracted more and more attention as a novel approach of multiplexing a set of orthogonal OAM modes on the same frequency channel to achieve high spectral efficiency(SE).However,the precondition for maintaining the orthogonality among different OAM modes is perfect alignment of the transmit and receive uniform circular arrays(UCAs),which is difficult to be satisfied in practical wireless communication ***,to achieve available multi-mode OAM broadband wireless communication,we first investigate the effect of oblique angles on the transmission performance of the multi-mode OAM broadband system in the non-parallel misalignment ***,we compare the UCA-based RF analog and baseband digital transceiver structures and corresponding beam steering *** analysis and numerical simulations validate that the SE of the misaligned multi-mode OAM broadband system is quite low,while analog and digital beam steering(DBS)both can significantly improve the SE of the ***,DBS can obtain higher SE than analog beam steering especially when the bandwidth and the number of array elements are large,which validates that the baseband digital transceiver with DBS is more suitable for multi-mode OAM broadband wireless communication systems in practice.

关键词： orbital angular momentum(OAM) uniform circular array(UCA) broadband wireless communication misalignment beam steering

An Evolutionary Approach to Improve the beam steering Performance over Conventional Approach in CHAA

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Journal of Communications and Information Networks 2023年第2期8卷 164-170页

作者： K Akhitha Gopi Ram National Institute of Technology Warangal 506004India

In this work,evolutionary algorithms are applied for the first time to achieve better radiation characteristics over the conventional beamforming algorithm in the concentric hexagonal antenna array(CHAA),which improves the performance of wireless *** signal classification(MUSIC)algorithm is employed for direction of arrival(DoA)*** conventional adaptive beam steering algorithm,least mean-square(LMS)algorithm,is used to steer the ***,the proposed approach is employed by novel particle swarm optimization(NPSO)to reduce sidelobe level(SLL)even further.A six-ring CHAA with 126 elements for DoA estimation and beam steering is *** simulation results of the MUSIC,LMS,NPSO,and particle swarm optimization(PSO)algorithms are provided for various DoAs.

关键词： smart antenna hexagonal array PSO MUSIC algorithm LMS algorithm DoA estimation beam steering NPSO

Bifunctional gap-plasmon metasurfaces for visible light: polarization-controlled unidirectional surface plasmon excitation and beam steering at normal incidence

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Light(Science & Applications) 2017年第1期6卷 7-14页

作者： Fei Ding Rucha Deshpande Sergey I Bozhevolnyi SDU Nano Optics University of Southern DenmarkCampusvej 55Odense DK-5230Denmark

Integration of multiple diversified functionalities into a single,planar and ultra-compact device has become an emerging research area with fascinating possibilities for realization of very dense integration and miniaturization in photonics that requires addressing formidable challenges,particularly for operation in the visible *** we design,fabricate and experimentally demonstrate bifunctional gap-plasmon metasurfaces for visible light,allowing for simultaneous polarization-controlled unidirectional surface plasmon polariton(SPP)excitation and beam steering at normal *** designed bifunctional metasurfaces,consisting of anisotropic gap-plasmon resonator arrays,produce two different linear phase gradients along the same direction for respective linear polarizations of incident light,resulting in distinctly different functionalities realized by the same *** proof-of-concept fabricated metasurfaces exhibit efficient(425%on average)unidirectional(extinction ratio 420 dB)SPP excitation within the wavelength range of 600–650 nm when illuminated with normally incident light polarized in the direction of the phase *** the same time,broadband(580–700 nm)beam steering(30.6°–37.9°)is realized when normally incident light is polarized perpendicularly to the phase gradient *** bifunctional metasurfaces developed in this study can enable advanced research and applications related to other distinct functionalities for photonics integration.

关键词： beam steering bifunctional gap-plasmon metasurfaces surface plasmon polaritons

Improved beam steering Method Using OAM Waves

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Computer Systems Science & Engineering 2023年第7期46卷 417-431页

作者： Nidal Qasem Ahmad Alamayreh Department of Electronics and Communications Engineering Al-Ahliyya Amman UniversityAmmanJordan

Orbital Angular Momentum(OAM)is an intrinsic feature of electromagnetic waves which has recently found many applications in several areas in radio and *** this paper,we use OAM wave characteristics to present a simple method for beam steering over both elevation and azimuth *** design overcomes some limitations of traditional steering methods,such as limited dynamic range of steering,the design complexity,bulky size of the steering structure,the limited bandwidth of operation,and low *** on OAM wave characteristics,the proposed steering method avoids design complexities by adopting a simple method for generating the OAM-carrying *** waves are generated by an array of Planar Circular Dipole(PCD)*** elements are designed to cover a wide bandwidth range between 3 and 30 *** transmitting array shows an enhanced gain value from 8.5 dBi to almost 11.5 dBi at the broadside *** the enhanced PCD-based OAM generation,the novelty of the design lies in a new method of beam *** steering is then performed by controlling the electrical feeding of the PCD elements;the beam azimuthal location is managed by turning off some of the PCD elements,while the elevation is determined by changing the gradient phase of excitation for the turned-on PCD *** analysis of the steering method is carried out by finding the mathematical model of the system and the generated *** performance has been verified through numerical simulators.

关键词： Antenna array bandwidth beam steering orbital angular momentum

Low-Cost beam steering that Covers the Entire Azimuthal Plane Powered by Amplitude-Only Synthesis of a Quintuple-Dipole Source

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Electromagnetic Science 2023年第3期1卷 100-113页

作者： Da Yi Zhiyang Qi Mingchun Tang Dajiang Li Yilin Lang Xingchang Wei The Key Laboratory of Dependable Service Computing in Cyber Physical Society Ministry of Education College of Microelectronics and Communication EngineeringChongqing UniversityChongqing 400044China Chongqing Key Laboratory of Space Information Network and Intelligent Information Fusion Chongqing UniversityChongqing 400044China College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027China

A new amplitude-only synthesis approach in quintuple electric dipoles(EDs)is proposed to enable the regulation of power flow in the azimuthal *** regulation methodology is investigated analytically with double ED,triple ED and quintuple ED ***,when the phase difference between the EDs switches,the double ED model,acting as a reconfigurable source,can work in two modes with different power flow directions,i.e.,unidirectional mode and bidirectional ***,from the triple ED model,it is verified that the power flow in the two working modes can be regulated to the desired direction in the azimuthal plane with high precision by controlling the feeding amplitudes of the ***,a quintuple ED model is developed to enhance the symmetry and consistency of the power flow regulation in the ***,a prototype of the azimuthal beam steering system,including digitally controlled radio-frequency(RF)frontend tuning circuits,optimized practical feeding elements,and an end-fire radiator,is designed,fabricated and *** unidirectional and bidirectional modes are observed,and satisfactory single-beam and dual-beam steering performance in the azimuthal plane is *** most phased arrays that realize beam steering by configuring phases,the beam steering of the proposed reconfigurable source in each mode can be arbitrarily synthesized only by the amplitudes of the quintuple feeding elements,which provides a new route for realizing low-cost and multifunctional beam-steering systems.

关键词： Electric dipole Reconfigurable devices Amplitude-only synthesis beam steering

Design and performance analysis of beam steering birefringent mercurous chloride acousto-optic device

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Chinese Journal of Acoustics 1995年第2期14卷 167-172页

作者： YANG Xuelin XU Jieping XIE Shengwu and ZHOU Jun(Depurtment of Applied Physics. Shanghai Jiaotong Uaiversity, Shanghai 200030)

The mercurous chloridc (Hg2Cl2) single crystal possesses unique acousto-optic (AO)properties, which make Hg2Cl2 Bragg cells desirable for various optical signal processing applications. Based on the design theory of beam stcering birefringent device, in this paper it is presented to design parameters of Hg2Cl2 devices. The performances of this new-type devices are also analyzed. The results show that, the sizes of Hg2Cl2 devices are much smaller than those of TeO2 devices, along with other good performances. Due to these advantages, the Hg2Cl2 Bragg cells can be expected to be keydevices in two-dimensional AO signal processing systems.

关键词： Hg_2Cl_2 crystal beam steering Bragg cells AO signal processing