- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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DUAL-BAND CIRCULAR POLARIZED SLOT ARRAY ANTENNA IN SUBSTRATE INTEGRATED WAVEGUIDE USING TWO PROPAGATION MODES FOR COMMUNICATION SATELLITES TRANSCEIVERS
摘要： A novel dual-band circularly-polarized slot array antenna aimed at LEO satellites communications where up-link and down-link operate at di?erent frequencies is introduced. By using higher order modes, the slots can be placed at points where current distributions are null for the fundamental mode. According to this idea, at the receiver frequency band the slots are placed to be excited by mode T E10 currents distribution, and at the transmitting band slots are forced to radiate according to mode T E20 currents distribution. A matching load termination is used to generate the required travelling wave to obtain the circular polarization, introducing low dissipation losses. Additionally, in this investigation an antenna feeder is also designed. Both the feeder and the slot antenna array are designed using Substrate Integrated Waveguide (SIW). The use of SIW makes easier the design of the transitions from the array to the microstrip input lines and the grounded-coplanar termination as well, relaxing fabrication constraints and tolerance.
关键词： dual-band,Substrate Integrated Waveguide,slot array antenna,circularly-polarized,communication satellites transceivers
更新于2025-09-23 15:19:57
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An ultracompact 3??1 MMI power-combiner based on Si slot-waveguide structures
摘要： Today, photonic integrated circuits (PIC) that work with a high-modulation speed (100Gb/s and beyond) are required to use more optical power to overcome the losses. One solution is to use a high-level laser with a hundred milliwatts power. However, for a microchip circuit, this solution can be problematic due to the non-linear e?ects and high cost. Therefore, to solve this issue, we propose a new design of a 3×1 multimode interference (MMI) power combiner based on a slot waveguide structure that can utilize slot-waveguide technology for reducing losses. In this study, the full-vectorial beam propagation method (FV-BPM) was used to ?nd the optimal geometrical parameters of the MMI coupler, inputs/output taper, and the slot waveguide structure. Simulation results show that after light propagation of 9.82 μm the beam combiner e?ciency can reach 97.6 % working within the C-band range. Also, to reduce back re?ection losses an angled MMI was designed using a ?nite di?erence time domain (FDTD) method and results show a low back re?ection of 40 dB. This unique design can lead to an e?cient and compact combiner for multiple coherent sources that work with PIC chips.
关键词： Slot-waveguide,MMI,FDTD,FV-BPM,Power-combiner
更新于2025-09-23 15:19:57
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Multiport optical power splitter design based on coupled-mode theory
摘要： We proposed a multiport T-shaped 1 x 8 balanced optical power splitter design based on asymmetric vertical silicon slot waveguides working on the principle of coupled-mode theory (CMT). The scheme of the power splitter is unique which offers strong field confinement of TE-polarized light and delivers the light to four ports each on two opposite side of the chip. By shifting the slot towards the outer sideline of the bend, the bending losses are reduced to 80% as compared to standard symmetric slot waveguide.
关键词： coupled-mode theory,asymmetric vertical silicon slot waveguides,bending losses,TE-polarized light,optical power splitter
更新于2025-09-23 15:19:57
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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) - A Waveguide Bandpass Filter with High Selectivity Using Slot Excitation
摘要： Under the excitation of a pair of shifted inclined slots, TE101, TE011 and TM110 modes in a single rectangular cavity are excited, and exploited to form a passband of bandpass filter (BPF). The pair of slots are fed through microstrip lines at the input and output port. Based on the single triple-mode rectangular cavity, a dual-cavity BPF is designed, fabricated and measured to enhance the selectivity of filter by cascading two single ones. The BPF could achieve about 32 MHz bandwidth at center frequency of 2.98 GHz, and two transmission zeros (TZs) at 2.925 and 3.005 GHz, leading to the suppression outside passband larger than 50 dB in the vicinity of center frequency.
关键词： Waveguide,Slot Excitation,High Selectivity,Bandpass Filter
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE International Symposium on Phased Array System & Technology (PAST) - Waltham, MA, USA (2019.10.15-2019.10.18)] 2019 IEEE International Symposium on Phased Array System & Technology (PAST) - An Additively Manufactured, All-metallic Frequency-scaled Ultra-wide Spectrum Element (AM-FUSE) Active Electronically Scanned Array (AESA) for Space-borne Applications
摘要： A new breed of the Frequency-scaled, Ultra-wide Spectrum Element (FUSE) is built entirely from a single piece of metal using direct metal laser sintering (DMLS) for space-borne missions. An active electronically scanned array (AESA) was built that includes an 8x4 linearly polarized aperture and low-profile feed circuitry that has eight true-time delay units (TDU) to fit inside a 3U CubeSat. This AESA operates over 1.5 GHz – 6 GHz, scanning +/- 45 degrees in azimuth with a very low active voltage standing wave ratio (active VSWR). The weight of the array with its combiner and beamforming boards is less than 3 lbs.
关键词： wideband,tapered-slot,CubeSat,additive manufacturing,AESA,connector-less,phased arrays,Vivaldi,FUSE,Antennas,space missions
更新于2025-09-23 15:19:57
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Gain characteristics of the hybrid slot waveguide amplifiers integrated with NaYF <sub/>4</sub> :Er <sup>3+</sup> NPs-PMMA covalently linked nanocomposites
摘要： Waveguide amplifiers based on slot waveguide have enormous capacity due to their ability to confine light strongly to a narrow slot waveguide. NaYF4:Er3+ nanoparticles-polymeric methyl methacrylate covalently linked nanocomposites were synthesized and filled into the slot. The stability and the Er3+ concentration doped in this novel material were improved. The slot waveguide was designed accurately. The rigorous numerical method, full-vector finite difference method, was used to analyze the modal characteristics and optimize the slot combined with the maximum power confinement in the slot and the minimum effective mode area of the slot. A four-level spectroscopic model pumped at 1480 nm was presented. The rate equations and propagation equations were solved and the gain characteristics of the slot waveguide amplifier were numerically simulated. The primary parameters were optimized. A net gain of 5.78 dB was achieved when the signal power was 0.001 mW at 1530 nm, pump power was 20 mW, Er3+ concentration was 1.3 (cid:1) 1027 m(cid:3)3, and the waveguide length was 1.5 cm.
关键词： NaYF4:Er3+ NPs-PMMA,slot waveguide,erbium-doped polymer waveguide amplifier,full-vector finite difference method,gain characteristics
更新于2025-09-23 15:19:57
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Device performance of standard strip, slot and hybrid plasmonic ??-ring resonator: a comparative study
摘要： In this paper, we presented three μ-ring resonator structures based on the standard strip, slot and hybrid plasmonic waveguides based on the SOI platform. A standard strip waveguide is formed by depositing a silicon core on a silica substrate. Whereas the slot waveguide is tailored by keeping a narrow air gap between two silicon strip waveguides. Finally, the hybrid plasmonic waveguide is composed of Metal-Air-Silicon structure, where the E-field is significantly enhanced in the narrow air gap. The ring radius is kept at 1.5 μm for the three designs. The transmission spectrum and E-field distribution of these structures are simulated using the finite element method (FEM). Silicon strip waveguide-based ring resonators are easy to fabricate but their sensitivity is quite low as compared to the other two designs. μ-ring resonator based on hybrid plasmonic waveguide shows the best sensitivity of 333.3 nm/RIU. While, slot waveguide based μ-ring resonator showed the best performance in the quality factor, the figure of merits and limit of detection. We believe that this comparative study will facilitate the researchers to choose the suitable waveguide design for ring resonators depending on their preferred application and fabrication technology available.
关键词： Conventional ring resonator,hybrid plasmonic ring resonator,sensitivity,figure of merit,limit of detection,Q-factor,slot ring resonator
更新于2025-09-23 15:19:57
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Beam Splitting of a Novel Triple-Beam Slot Antenna Array Based on Radial Gap Waveguide
摘要： We present a phenomenon of beam splitting caused by asymmetric boundaries. We design and manufacture a novel triple-beam slot antenna array working at X-band to verify this phenomenon and show its potential applications. The corporate-feed slot antenna is based on a radial ridge gap waveguide (RGW) power divider, and is excited by a central coaxial connector. To achieve good efficiency, a radial SMA-RGW transition structure is proposed. Six different symmetrical and asymmetrical triple-beam RGW slot antenna arrays are mentioned in this paper. Among them, two symmetrical and one asymmetrical triple-beam RGW slot antenna arrays are fabricated and measured, and the measured results have good agreement with full-wave simulations, demonstrating stable performance of the proposed antenna array. Compared with the traditional slot antenna array, the proposal is capable of generating any number of beams in theory, especially odd beams, and each beam can be individually designed. The proposed shared-aperture radial multi-beam antenna can achieve simultaneously multi-directional coverage. It can meet the needs of multi-target tracking and imaging in blind spot detection and collision warning scenarios of the vehicular radar system. It also has potential value to satisfy the need of large-scale users connection in the wide-area continuous coverage scenario of the fifth generation communication system.
关键词： Beam splitting,slot antenna array,radial feeding network,ridge gap waveguide
更新于2025-09-23 15:19:57
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[IEEE 2018 IEEE Asia-Pacific Conference on Antennas and Propagation (APCAP) - Auckland (2018.8.5-2018.8.8)] 2018 IEEE Asia-Pacific Conference on Antennas and Propagation (APCAP) - A Miniaturized Double-Vivaldi Antenna With Improved Gain Based on a Novel Metasurface
摘要： A miniaturized double-Vivaldi antenna (DVA) with high gain based on metasurface (MS) is proposed. A pair of defected ground slots (DGS) are added to the edges of the antenna to extend the low-end frequency limitation from 2.15 GHz to 1 GHz. Then, the gain of DVA is improved obviously in a wide frequency band by the inclusion of a MS in the aperture. The novel unit cell of the MS in our design is a two-stub-loaded split-ring resonator (TSLSRR), which has compact size, wide frequency band, and low-return loss. Finally, to verify the designed methods, DVA, DVA with DGS (DVA-DGS), DVA with DGS and MS (DVA-DGS-MS) ware successfully designed, and it show an overall size of 80 mm × 150 mm × 1 mm.
关键词： wideband and low-return loss metasurface,Double-Vivaldi antenna,high-gain,defected ground slot
更新于2025-09-19 17:15:36
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[IEEE 2018 XXIIIrd International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory (DIPED) - Tbilisi (2018.9.24-2018.9.27)] 2018 XXIIIrd International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory (DIPED) - An UWB Antenna Design Having Band-Reject Characteristic by Y-Shaped Strip
摘要： In this study, a new UWB antenna design that shows the band-notched characteristic for UWB application has been designed. To model the antenna, a Hyperbolic-Perforated (HP) method based on two parasitic patches and a parasitic slot (62) is used. As a result, a frequency response is obtained in the band range of 3.1-10.6 GHz for UWB systems. Based on the results, it further refines the core findings, significance of the research, and suggestions for future studies.
关键词： band-notched characteristic,UWB antenna,Hyperbolic-Perforated method,parasitic patches,parasitic slot
更新于2025-09-19 17:15:36