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- 摘要
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- 实验方案
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[IEEE 2019 Electric Power Quality and Supply Reliability Conference (PQ) & 2019 Symposium on Electrical Engineering and Mechatronics (SEEM) - K?¤rdla, Estonia (2019.6.12-2019.6.15)] 2019 Electric Power Quality and Supply Reliability Conference (PQ) & 2019 Symposium on Electrical Engineering and Mechatronics (SEEM) - Analysis of Harmonic Current Stability and Summation of LED Lamps
摘要： In this paper, radio-frequency (RF) electromagnetic field (EMF) exposure evaluations are conducted in the frequency range 10–60 GHz for array antennas intended for user equipment (UE) and low-power radio base stations in 5G mobile communication systems. A systematic study based on numerical power density simulations considering effects of frequency, array size, array topology, distance to exposed part of human body, and beam steering range is presented whereby the maximum transmitted power to comply with RF EMF exposure limits specified by the International Commission on Non-Ionizing Radiation Protection, the US Federal Communications Commission, and the Institute of Electrical and Electronics Engineers is determined. The maximum transmitted power is related to the maximum equivalent isotropically radiated power to highlight the relevance of the output power restrictions for a communication channel. A comparison between the simulation and measurement data is provided for a canonical monopole antenna. For small distances, with the antennas transmitting directly toward the human body, it is found that the maximum transmitted power is significantly below the UE power levels used in existing third and fourth generation mobile communication systems. Results for other conceivable exposure scenarios based on technical solutions that could allow for larger output power levels are also discussed. The obtained results constitute valuable information for the design of future mobile communication systems and for the standardization of EMF compliance assessment procedures of 5G devices and equipment.
关键词： mobile user equipment,5G mobile communication,RF EMF exposure,beam steering,radio base station,mobile device,antenna arrays
更新于2025-09-19 17:13:59
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Liquid crystal programmable metasurface for terahertz beam steering
摘要： The coding metasurface integrated with tunable materials offers an attractive alternative to manipulate the THz beam dynamically. In this work, we demonstrate a THz programmable metasurface based on liquid crystal. The phase pro?le on the metasurface could be dynamically manipulated by switching the “0” and “1” states of each element. The programmable metasurface could de?ect the THz beam using the designed coding sequence, and a maximum de?ection angle of 32(cid:2) has been achieved. The presented design opens a route of beamforming for THz communication.
关键词： beamforming,programmable metasurface,THz beam steering,liquid crystal
更新于2025-09-19 17:13:59
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[IEEE 2019 International Topical Meeting on Microwave Photonics (MWP) - Ottawa, ON, Canada (2019.10.7-2019.10.10)] 2019 International Topical Meeting on Microwave Photonics (MWP) - Multi-core Fiber Technology supporting MIMO and Photonic Beamforming in 5G Multi-Antenna Systems : (Invited paper)
摘要： This paper describes and experimentally validates different multi-antenna system applications supported by a multi- core fiber (MCF) optical fronthaul. The MCF fronthaul enables the simultaneous transmission of different optical data streams at the same wavelength by the spatial multiplexing of multiple-input multiple-output (MIMO) signals. In addition, the MCF enables simultaneous radio beamforming by transmitting the same optical data signal with different phase or time delays to each antenna element. Both MIMO and beamforming capabilities are required for 5G multi-antenna systems. Experimental demonstrations of 4×4 MIMO transmission and multi-beam 4×1 beamforming using a commercially available 4-core fiber are reported in this work. Optical beam-steering in 5G is achieved using a Si3N4 photonic chip based on optical ring resonators (ORRs) that enables the continuous and centralized tuning of the time delay applied to each antenna element.
关键词： integrated photonics,beamforming,MIMO,Multi-core fiber,multi-antenna systems,radio beam-steering,optical ring resonator (ORR)
更新于2025-09-16 10:30:52
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A Lateral MOS-Capacitor Enabled ITO Mach-Zehnder Modulator for Beam Steering
摘要： Here, we experimentally demonstrate an Indium Tin Oxide (ITO) Mach-Zehnder interferometer heterogeneously integrated in silicon photonics. The phase shifter section is realized in a novel lateral MOS configuration, which, due to favorable electrostatic overlap, leads to efficient modulation (VπL = 63 V.μm). This is achieved by (i) selecting a strong index changing material (ITO) and (ii) improving the field-overlap as verified by the electrostatic field lines. Furthermore, we show that this platform serves as a building block in an end-fire silicon photonics optical phased array (OPA) with a half-wavelength pitch within the waveguides with anticipated performance, including narrow main beam lobe (<3°) and >10 dB suppression of the side lobes, while electrostatically steering the emission profile up to ±80°, and if further engineered, can lead not only towards nanosecond-fast beam steering capabilities in LiDAR systems but also in holographic display, free-space optical communications, and optical switches.
关键词： Electro-optic Modulator,Indium Tin Oxide (ITO),Phased Arrays,LiDAR,Mach Zehnder,Beam Steering
更新于2025-09-16 10:30:52
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[IEEE 2019 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - Guangzhou, China (2019.5.19-2019.5.22)] 2019 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - Design of a high outband rejection cross-coupled SIW filter for millimeter wave communications
摘要： In this paper, we demonstrate ultra-fast millimeter wave beam steering with settling times below 50 ps. A phased array antenna with two elements is employed to realize beam steering. The phased array feeder is implemented with a recently introduced time delay line that provides, at the same time, an ultra-fast tunability, broadband operation, and continuous tuning. Our implementation is used to perform symbol-by-symbol steering. In our demonstration, the beam direction is switched between two sequentially transmitted symbols toward two receivers placed 30° apart. We show the successful symbol-by-symbol steering for data streams as fast as 10 GBd. The suggested scheme shows that the ultra-fast beam steering is becoming practical and might ultimately enable novel high bit-rate multiple access schemes.
关键词： Ultra-fast beam steering,radio access network,microwave photonics,millimeter wave communication
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE Canadian Conference of Electrical and Computer Engineering (CCECE) - Edmonton, AB, Canada (2019.5.5-2019.5.8)] 2019 IEEE Canadian Conference of Electrical and Computer Engineering (CCECE) - Electronically Steerable Quasi-Uniform Leaky-Wave Antenna Based on Substrate Integrated Waveguide
摘要： In this paper, we introduce a novel electronically beam steered leaky-wave antenna. The proposed quasi-uniform leaky-wave antenna is implemented on a substrate integrated waveguide. The introduction of switches over the slots on the broad wall of the antenna leads to beam steering with variations in the side-lobe levels, directivity, and gain of the antenna. A center frequency of 28.5 GHz has been selected. The optimized length, width, and height of the antenna are 68 mm, 24 mm, and 0.3 mm, respectively. Scanning capability, low profile, simplicity, and high gain in the proposed structure makes it a suitable candidate for 5G navigation systems and cellular networks.
关键词： antenna,switch,beam-steering,slot
更新于2025-09-12 10:27:22
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Fast electro-optic switching for coherent laser ranging and velocimetry
摘要： The growth of 3D imaging across a range of sectors has driven a demand for beam steering technology. Fields as diverse as autonomous vehicles and medical imaging can benefit from a high speed, adaptable method of beam steering. We present a monolithic, submicrosecond electro-optic switch as a solution toward the need for reliability, speed, dynamic addressability, and compactness. Here, we demonstrate a laboratory-scale, solid-state light detection and ranging system, using the electro-optic switch to launch modulated coherent light into free space and then to collect the reflected signal. We use coherent detection of the reflected light to simultaneously extract the range and axial velocity of targets at each of the several electronically addressable output ports.
关键词： electro-optic switching,beam steering,coherent laser ranging,velocimetry,LIDAR
更新于2025-09-12 10:27:22
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[IEEE 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Paris, France (2019.9.1-2019.9.6)] 2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Bifunctional metasurface for polarization-controlled beam steering and excitation of spoof surface plasmon polariton
摘要： Based on the combination of propagation phase with geometric phase, to the best of our knowledge, a new reflective metasurface which can control the direction of reflected waves and excite spoof surface plasmon polariton (SSPP) simultaneously is proposed and numerically demonstrated for the circular polarization incident waves. The incident waves can be converted into SSP with longitudinal wave vector kx = 1.2 k0 or anomalously reflected with reflection angle (cid:2)r = 13.9o under the illumination of the left or the right circular polarization beam, respectively. The respective converting efficiency of the left and right circular polarization can reach up to 70% and 82% at the frequency of 0.3 THz. Our study may open up new routes for polarization-related antennas, detectors and other practical terahertz devices.
关键词： spoof surface plasmon polariton,SSPP,beam steering,polarization-controlled,metasurface
更新于2025-09-12 10:27:22
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Integrated Plasmonic Nanoantenna Gratings for Large Area Coherent Optical Source
摘要： The emission of coherent light from a large area with a controlled directivity is required for high quality holographic system. In application domains like automotive, such a source needs to be fully planar for compactness and portability. It can be made of discretized sub-sources as long as they remain coherent and with the same directivity. We have considered here an array of connected waveguides covering the surface of a glass substrate. These waveguides spread the laser light out on the whole surface. Discretized plasmonic nanoantennas positioned at specific locations along the waveguides realise then the out-of-plane coherent beam steering.
关键词： plasmonic nanoantennas,waveguide,beam steering,coherent optical source,holographic system
更新于2025-09-12 10:27:22
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - 360° on Chip Optical Beam Steering Based on Superposition of Planar Spiral Orbital Angular Momentum Waves
摘要： Optical beam steering has been pursued in the past decade, largely motivated by its potential applications including optical communication and laser radar systems. Optical phased array (OPA) is a promising beam steering method, which has the potential advantages of low cost, chip scale, high resolution, fast scanning [1]. However, a main problem with current OPAs is the limited scanning angle. Steering angle of OPAs based on out-of-plane emitting planar waveguide gratings is typically < 50 degrees. End-fire OPA has a larger steering angle but still will be restricted to <180 degrees due to its geometry [2]. Circular OPA can provide 360-degree beam steering [3-4], but the existing proposals require large number of control elements which makes it very hard to realize. We report a silicon based OPA which is built on our previous works on orbital angular momentum (OAM) [5-6]. The OPA consists of N concentric micro-ring OAM emitters that, when injected with a transverse magnetic (TM) polarized mode, are capable of emitting ‘sideways’ – a planar spiral orbital angular momentum (PS-OAM) beam whose phase fronts spiral outwards in the micro-ring plane with li number of arms, as given by the dipole model [7-9], by superposition of such PS-OAM waves or azimuthal Fourier harmonics, ∑Ni=1aiexp(jliφ)exp(jφi),. The superposition of such PS-OAM waves is capable of providing a practical realization of beamforming in radiofrequency and optical domain [7-9], by controlling their amplitude ai, phase φi, and topological charge li. A narrow beam can be rotated 360 degrees easily by adjusting the phase shifters, and with its 3 dB beamwidth decreases with higher number of PS-OAM modes.
关键词： Optical phased array,Orbital angular momentum,Optical beam steering,Silicon photonics
更新于2025-09-11 14:15:04