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oe1(光电查) - 科学论文

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出版时间
  • 2018
研究主题
  • Schottky diodes
  • frequency multipliers
  • submillimeter-wave technology
  • terahertz technology.
  • Submillimeter-wave sources
应用领域
  • Optoelectronic Information Science and Engineering
机构单位
  • California Institute of Technology
201 条数据
?? 中文（中国） ▾

  • Substrate-Integrated-Waveguide Power Dividers: An Overview of the Current Technology

    摘要： Power dividers are important components of microwave/millimeter wave (mm-wave) circuit design. This article provides a comprehensive review of the state-of-the-art substrate-integrated-waveguide (SIW) power dividers/combiners. SIW technology converts waveguide-like structures into planar form, compensates for the drawbacks of microstrip structures at higher-frequency circuit designs, and minimizes production complexity and costs compared to conventional waveguide structures. An overview of how traditional dividers have progressively adopted the SIW technique is presented and a comparative performance analysis of the divider types and practical paradigm show the future potential of SIW technology.

    关键词： microwave,power dividers,Substrate-integrated-waveguide (SIW),circuit design,millimeter wave

    更新于2025-09-12 10:27:22

  • [IEEE 2019 IEEE/MTT-S International Microwave Symposium - IMS 2019 - Boston, MA, USA (2019.6.2-2019.6.7)] 2019 IEEE MTT-S International Microwave Symposium (IMS) - Liquid Crystal Phase Shifter Based on Nonradiative Dielectric Waveguide Topology at W-Band

    摘要： This paper presents a continuously tunable nonradiative dielectric waveguide (NRD) phase shifter based on liquid crystal (LC) technology at W-band. LC is inserted in the NRD’s dielectric core to obtain tunability. Compared to other dielectric waveguides, which are prone to radiation losses, the NRD is radiation free even at bends and discontinuities. A maximum differential phase shift of 280? was achieved with an electric biasing voltage of ±150 V, accompanied with insertion losses between 2.9 dB to 4.9 dB, resulting in a maximum Figure-of-Merit of 85 ?/dB.

    关键词： millimeter wave devices,tunable circuits and devices,phase shifter,Liquid crystal,nonradiative dielectric waveguide

    更新于2025-09-12 10:27:22

  • [IEEE 2019 IEEE/MTT-S International Microwave Symposium - IMS 2019 - Boston, MA, USA (2019.6.2-2019.6.7)] 2019 IEEE MTT-S International Microwave Symposium (IMS) - W-band Finite Ground Coplanar Waveguide (FG-CPW) using Laser Enhanced Direct-Print Additive Manufacturing (LE-DPAM)

    摘要： Design, fabrication, and measurement of finite ground coplanar waveguides (FG-CPWs) operating up to 110 GHz is demonstrated using additive manufacturing (AM) technology. FG-CPWs were fabricated using laser enhanced direct-print additive manufacturing, where laser-machining at 355 nm or 1064 nm wavelength was employed along with fused deposition modeling and micro-dispensing in a single digital manufacturing platform. This approach provides high dimensional accuracy that is required by mm-wave packaging systems. The characterization of laser machining at wavelengths of both 355 nm and 1064 nm was examined with specific focus on the feature size and dimensional accuracy. Several FG-CPW designs for 50 and 60 ohms are characterized and compared against a FG-CPW line on a commercially available calibration substrate. Attenuation as low as ~0.3 dB/mm at 110 GHz is achieved. To the best of the authors’ knowledge, this is the first reported experimental result for transmission lines at W-band using laser enhanced direct-print additive manufacturing (LE-DPAM).

    关键词： transmission lines,W-band,laser machining,additive manufacturing,FG-CPW,millimeter wave,3D Printing,110 GHz

    更新于2025-09-12 10:27:22

  • [IEEE 2019 IEEE/MTT-S International Microwave Symposium - IMS 2019 - Boston, MA, USA (2019.6.2-2019.6.7)] 2019 IEEE MTT-S International Microwave Symposium (IMS) - Miniaturized Quartz Waveguide Filter using Double-Folded Structure

    摘要： A miniaturized 28 GHz quartz waveguide band-pass filter using a double-folded structure has been developed. The double-folded structure is used for a footprint reduction less than half of a current single-folded quartz waveguide filter. Some analyses using EM simulation were carried out for studying an electromagnetic coupling between the waveguide resonators. For the double-folded structure, an inductive coupling is appropriate for a main coupling in the vertical direction. The fabricated filter, an 8-pole Chebyshev BPF, has a size of 6.9 × 7.2 × 3.1 mm3 and measured insertion loss was very low such as 0.74 dB which is same as the current single-folded type. Besides, an 8-pole quasi-elliptic BPF was simulated and its attenuation performance was remarkably improved.

    关键词： TE mode,cross-coupling,double-folded waveguide filter,millimeter wave,transmission zero,quartz

    更新于2025-09-12 10:27:22

  • Transmission characteristics of photonic crystal waveguide with array square Al2O3 rods lattice in millimeter wave

    摘要： In this work, the transmission characteristics of a millimeter wave photonic crystal waveguide formed by square lattice Al2O3 ceramic rods array are numerically and experimentally investigated. Based on the numerical simulations of photonic crystals, the corresponding experiments are performed, which are consistent with the numerical results. The transmission efficiency of photonic crystal waveguide with three-dimensional model is studied using finite element method. The measured transmission efficiency of the prototype photonic crystal waveguide is better than ?1.5 dB in frequency range 23.6–29.8 GHz. Since the designed photonic crystal waveguide is wide band, low loss and easy integration; it is potential to be applied in millimeter communication systems.

    关键词： Defects,Millimeter wave,Photonic crystal structure

    更新于2025-09-11 14:15:04

  • Air-Filled Substrate Integrated Waveguide Fed Magneto-Electric Dipole Antenna Array for Millimeter-Wave Applications

    摘要： A substrate integrated magneto-electric (ME) dipole antenna array with an improved radiation efficiency is presented in the 28-GHz band. A novel full-corporate air-filled substrate integrated waveguide (SIW) feed network with low losses is designed and realized by utilizing the low-cost printed circuit board (PCB) facilities. Different from most previous millimeter-wave planar arrays consisting of 2 × 2 sub-arrays, an SIW fed sub-array with a larger size of 2 × 4 is investigated to simplify the configuration of the major portion of the array feed network, which is of importance to the successful realization of the air-filled SIW feed network. An 8 × 8 array prototype with a four-layered geometry is fabricated and measured to verify the design. The array has an impedance bandwidth of 25.9%, a gain up to 26 dBi and stable radiation patterns over the operating band. Benefitted from the absence of the significant dielectric loss in the feed network, a high antenna efficiency of 80% is also achieved. The proposed design provides an effective method to improve the achievable gain and efficiency characteristics of the substrate-integrated arrays with a large size that are attractive for millimeter-wave wireless applications.

    关键词： feed network,Antenna array,aperture-coupled magneto-electric (ME) dipole antenna,dielectric loss,millimeter-wave,air-filled substrate integrated waveguide (SIW)

    更新于2025-09-11 14:15:04

  • Liquid Crystal Based Dielectric Waveguide Phase Shifters for Phased Arrays at W-Band

    摘要： In this work, the feasibility of microwave liquid crystal based dielectric waveguide phased shifters is investigated in a phased rod antenna array for the ?rst time. For this, a 1 × 4 rod antenna array is designed including the phase shifters as well as a cascaded E-plane power divider network. As core elements, the phase shifter are designed as continuously tunable subwavelength ?bers, partially ?lled with a newly speci?cally synthesized microwave liquid crystal, exhibiting a maximum FoM 145?/dB at 102.5 GHz. As proof-of-concept, a simpli?ed electric biasing network is developed, demonstrating its beam steering capability by changing the scanning angle between 0?, ?25? and +15? with three different voltage distributions. The antenna array is well matched throughout the complete W-band with a input re?ection below ?10 dB. The measured antenna gain is between 11.5 to 9.1 dBi at 85 GHz accompanied with a side lobe level between ?12 to ?7 dB, depending on the steering con?guration.

    关键词： dielectric waveguide,millimeter wave devices,Phased array,microwave liquid crystal

    更新于2025-09-11 14:15:04

  • Cross-Configuration Substrate Integrated Waveguide Beamforming Network for 1D and 2D Beam Patterns

    摘要： This paper presents the simulated and measured results of a dual-layer substrate integrated waveguide (SIW) beamforming network utilizing an 8 × 8 cross-con?guration Butler matrix over a frequency range of 28.5 to 31.5 GHz. By arranging the input ports on the bottom SIW layer and employing dual-layer passband ?lters as a detachment point, the top SIW layer can be interchanged with the purpose of exploring one-dimensional and two-dimensional broadside beam patterns. Although Butler matrices are not typically utilized for beamforming in this con?guration, two examples of interchangeable top layer arrays are demonstrated; the ?rst being a 2 × 8 slot antenna array for 1-D scanning, and the second being a 2 × 4 center-slot array for 2-D scanning. Each of the beamforming network’s simulated and measured 10 dB bandwidth is demonstrated over a range of 28.5 to 31.5 GHz. Additional design details and dimensions are speci?ed for the aforementioned passband ?lter transitions, as well as for each of the slot antenna arrays.

    关键词： millimeter-wave,dual-layer SIW ?lters,slot antenna array,Butler matrix,substrate integrated waveguide (SIW)

    更新于2025-09-11 14:15:04

  • [IEEE 2019 IEEE Research and Applications of Photonics in Defense Conference (RAPID) - Miramar Beach, FL, USA (2019.8.19-2019.8.21)] 2019 IEEE Research and Applications of Photonics in Defense Conference (RAPID) - Study of 90-GHz Phased Array Antenna System Based on Chromatic Dispersion Effect in the Optical Fiber

    摘要： Phased array antenna system is evaluated in the 90-GHz band using fiber-dispersion-based true time delay. Phase differences are induced by transmission of the optical fiber, without any additional equipment. Beam steering angle with a range of 5 degrees is successfully demonstrated with four horn-antenna elements.

    关键词： phased array antenna,radio over fiber,fiber chromatic dispersion,millimeter-wave

    更新于2025-09-11 14:15:04

  • Long-Pulse Uncooled Copper Magnet for Gyrotron

    摘要： The operation of a gyrotron requires a strong, stable magnetic ?eld over time. Working in the CW mode requires complex/cryogen solenoid cooling systems. Working in the pulse mode is possible with a simple solenoid, but only for short pulses, typically up to 50 μs. In this article, an intermediate working point for the gyrotron is presented: a pulsed gyrotron with a simple uncooled solenoid, which is capable of producing relatively long pulses of ～10 ms. To power a longer pulse with a simple solenoid, a super-capacitor (SC)-based system has been designed, which enables the extension of the operation of pulsed gyrotrons to tens of milliseconds, while keeping the system simplicity, without a cooling system for the solenoid. The setup was realized and a 27-ms current pulse of 1.1 kA was obtained through a gyrotron with a simple copper solenoid with a stability of ～0.3%. A 5-kW/10-ms radiation pulse at 28 GHz was measured from the gyrotron. This setup enables the use of a rather simple solenoid and a gyrotron and still obtains a rather long radiation pulse. This concept may open a new regime for pulsed gyrotrons.

    关键词： Gyrotron,long pulse,magnetic ?eld,solenoid,millimeter wave

    更新于2025-09-11 14:15:04