Design of a low-loss microstrip diplexer with a compact size based on coupled meandrous open-loop resonators

An equalizer based on multilayered half mode substrate integrated waveguide (HMSIW) structures with highQ-factor, low loss, and compact size is proposed for the first time. Resonant cavities distributing in the upper substrate and the bottom substrate, with the middle substrate layer which works as the transmission line together, constitute a multilayer structure. The design method and theoretical analysis are summarized first. The mode analysis, simulated results, and measured results are all provided. The measured results show a good performance and are in agreement with the simulated results, and the maximum attenuation slope reaches −16 dB over 12.5 GHz~14.5 GHz. With the use of absorbing pillars, the attenuation andQvalue can be tuned more easily than the other planar equalizers. Compared with the SIW equalizer, the size of this structure reduces by 50%. Furthermore, this structure is suitable for the miniaturization development of equalizers.

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A Low-Loss Self-Packaged Magic-T With Compact Size Using SISL Technology

IEEE Microwave and Wireless Components Letters ◽

10.1109/lmwc.2017.2766566 ◽

2018 ◽

Vol 28 (1) ◽

pp. 13-15 ◽

Cited By ~ 3

Author(s):

Yongqiang Wang ◽

Kaixue Ma ◽

Shouxian Mou

Keyword(s):

Low Loss ◽

Compact Size

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Progress of liquid crystal adaptive optics for applications in ground-based telescopes

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa841 ◽

2020 ◽

Vol 494 (3) ◽

pp. 3536-3540

Author(s):

Xingyun Zhang ◽

Zhaoliang Cao ◽

Quanquan Mu ◽

Dayu Li ◽

Zenghui Peng ◽

...

Keyword(s):

Energy Efficiency ◽

Liquid Crystal ◽

Adaptive Optics ◽

Low Cost ◽

Response Speed ◽

Open Loop ◽

Loop Control ◽

Compact Size ◽

Control Scheme ◽

Resolution Imaging

ABSTRACT Liquid crystal (LC) adaptive optics systems (AOS) can potentially be used in ground-based large aperture telescopes, because of their high spatial resolution, low cost and compact size. However, their disadvantages, such as low energy efficiency and slow response speed, still hinder their application. In this paper, we demonstrate solutions to these problems. With newly synthesized fast nematic LC material and using an overdriving technique, the response time of a LC wavefront corrector was reduced to 0.75 ms. Under an open-loop control scheme, a novel optical system was designed to improve the energy efficiency of LC AOS. With those problems resolved, a LC AOS was built for a 1.23-m telescope. This system has a disturbance rejection bandwidth of 80 Hz, and could fully use the energy of 400–900 nm wavebands. Observation results showed that the diffraction limit resolution imaging of the telescope could be obtained after correction, which indicates that the LC AOS is ready to be used in ground-based telescopes for visible waveband imaging.

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The Design of New Structures of Planar Diplexers Using Microstrip Resonators

Advances in Wireless Technologies and Telecommunication - Handbook of Research on Advanced Trends in Microwave and Communication Engineering ◽

10.4018/978-1-5225-0773-4.ch006 ◽

2017 ◽

pp. 170-204

Author(s):

Abdessamed Chinig ◽

Ahmed Errkik ◽

Abdelali Tajmouati ◽

Hamid Bennis ◽

Jamal Zbitou ◽

...

Keyword(s):

Ground Plane ◽

Open Loop ◽

Analytic Method ◽

Input Output ◽

The Third ◽

Full Wave ◽

Compact Size ◽

Microstrip Resonators ◽

Band Pass ◽

Interesting Solution

In this chapter, three planar diplexers based on microstrip resonators are presented. An overview on diplexers is introduced. Then, two designed and fabricated microstrip diplexers with compact size and good performances are exposed. The first diplexer is designed using open loop resonators while the second circuit is achieved based on triangular loop resonators. The third structure represents a compact diplexer designed by using a pair of H-shaped resonators coupled with a coupling patch and two Input/Output (I/O) feed lines. The incorporated slots in the ground plane of the proposed circuit allow the control of the resonant frequencies and enhance its electrical performances. Furthermore, the introduction of these slots represents an interesting solution to miniaturize the microwave filter and diplexer. An analytic method is applied to extract the equivalent LC model of the band pass filters and diplexer. A full wave electromagnetic Analysis is achieved to evaluate the electrical performances of the proposed diplexers by using ADS and CST-MWS.

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A Dual-Fuzzy Pressure Compensation Based Symmetric Control Scheme of Single-Rod Electro-Hydraulic Actuator

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.816-817.379 ◽

2013 ◽

Vol 816-817 ◽

pp. 379-384

Author(s):

Li Peng Wang ◽

Jun Zheng Wang ◽

Yu Dong He ◽

Jiang Bo Zhao

Keyword(s):

Fast Response ◽

Open Loop ◽

Hydraulic Actuator ◽

Fuzzy Pid Controller ◽

Control Precision ◽

Compact Size ◽

Control Scheme ◽

Pressure Feedback ◽

Pressure Compensation ◽

Feedback Algorithm

In hydraulic robots, single-rod electro-hydraulic actuator is widely employed for fast response, small size-to-power ratio, large output force and compact size. The differences of open loop gains and other parameters make the dynamic characteristics of two moving directions asymmetric in symmetric valve controlled asymmetric cylinder system. To ensure robots moving smoothly and improve control precision, a novel pressure compensation based symmetric control scheme is proposed. Pressure feedback algorithm is mathematically proved feasible. Therefore, a displacement and pressure signals fused fuzzy PID controller is designed. Simulation results verify the feasibility and validity for compensating the asymmetric problems.

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An Ultra-Compact Design of Plasmonic Memristor with Low Loss and High Extinction Efficiency Based on Enhanced Interaction between Filament and Concentrated Plasmon

Photonics ◽

10.3390/photonics8100437 ◽

2021 ◽

Vol 8 (10) ◽

pp. 437

Author(s):

Ye Tian ◽

Saiwen Zhang ◽

Weishi Tan

Keyword(s):

Numerical Simulation ◽

Low Loss ◽

Switching Device ◽

Extinction Efficiency ◽

Vertical Coupling ◽

Compact Size ◽

Telecommunication Wavelength ◽

Numerical Design ◽

Low Insertion Loss ◽

Compact Design

We present a numerical design of the plasmonic memristive switching device operated at the telecommunication wavelength of 1.55 μm, which consists of a triangle-shaped metal taper mounted on top of a Si waveguide, with rational doping in the area below the apex of the taper. This device can achieve optimal vertical coupling of light energy from the Si waveguide to the plasmonic region and, at the same time, focus the plasmon into the apex of the metal taper. Moreover, the area with concentrated plasmon is overlapped with that where the memristive switching occurs, due to the formation/removal of the metallic nano-filament. As a result, the highly distinct transmission induced by the switching of the plasmonic memristor can be produced because of the maximized interactions between the filament and the plasmon. Our numerical simulation shows that the device hasa compact size (610 nm), low insertion loss (~1 dB), and high extinction efficiency (4.6 dB/μm). Additionally, we point out that stabilizing the size of the filament is critical to improve the operation repeatability of the plasmonic memristive switching device.

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