An in-line coaxial-to-circular waveguide transition at X band

AbstractA wideband transition from the coaxial TEM mode to the TM01 mode of the circular waveguide with in-line input-output architecture is proposed in this paper. The transition employs multi-stage stepped impedance transformer to achieve wideband responses. Both mode transition and impedance matching characteristics are discussed in the paper. A demonstrator is developed and validated experimentally. As compared with some recently published reports, a better performance is observed. Moreover, the developed transition could facilitate the mechanical fabrication more easily. It can be found wide applications such as the circular waveguide based slot array antenna, the nondestructive detection, cracks inside the conductive pipes, and so on.

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An In-Line Coaxial-to-Waveguide Transition for Q-Band Single-Feed-Per-Beam Antenna Systems

Applied Sciences ◽

10.3390/app11062524 ◽

2021 ◽

Vol 11 (6) ◽

pp. 2524

Author(s):

Marco Simone ◽

Alessandro Fanti ◽

Matteo Bruno Lodi ◽

Tonino Pisanu ◽

Giuseppe Mazzarella

Keyword(s):

Return Loss ◽

Transverse Section ◽

Impedance Matching ◽

Coaxial Cable ◽

Scattering Parameters ◽

High Frequencies ◽

Waveguide Transition ◽

Tem Mode ◽

Parameters Analysis ◽

Space Occupation

An in-line transition between a coaxial cable and rectangular waveguide operating in Q-band (33–50 GHz) is presented. The aim of the work is to minimize the modifications in the waveguide to the strictly necessary to overcome the manufacturing issues due to the high frequencies involved. In addition, the transition is compact and it does not increase the space occupation on the transverse section, this suggests its application in horn antennas clusters arrangement. The operating principle consists of both a modal conversion and an impedance matching between the devices. The modal conversion is realized in an intermediate region, where the coaxial penetrates in the waveguide: the device geometry is designed so that the electric field in the transition is a trade-off between the TEM mode of the coaxial and the TE10 of the guide. A shaped waveguide backshort and a reactive air gap in the coaxial cable co-participate to achieve the matching. An optimized Chebyshev stepped transformer completes the transition to fulfil the impedance mismatch with the full waveguide. The design issues and technological aspects are considered. The influences of the feeding pin misalignment, the presence of groove is included in the analysis and these practical aspects are discussed and numerically validated via the scattering parameters analysis of the proposed design. The return loss is higher than 25 dB over the whole Q-band.

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Design, optimization and development of X-band microstrip patch antenna array for high gain, low sidelobes and impedance matching

2008 Second International Conference on Electrical Engineering ◽

10.1109/icee.2008.4553908 ◽

2008 ◽

Author(s):

Ghulam Ahmad

Keyword(s):

Design Optimization ◽

Antenna Array ◽

Patch Antenna ◽

Impedance Matching ◽

High Gain ◽

Microstrip Patch Antenna ◽

Microstrip Patch ◽

X Band

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Multi-Stage System Identification of a Gas Turbine

Volume 6: Ceramics; Controls, Diagnostics and Instrumentation; Education; Manufacturing Materials and Metallurgy ◽

10.1115/gt2017-64777 ◽

2017 ◽

Author(s):

Amit Pandey ◽

Maurício de Oliveira ◽

Chad M. Holcomb

Keyword(s):

Gas Turbine ◽

Closed Loop ◽

Open Loop ◽

Loop System ◽

Closed Loop Control ◽

Input Output ◽

Open Loop System ◽

Loop Control ◽

Multi Stage ◽

Identification Techniques

Several techniques have recently been proposed to identify open-loop system models from input-output data obtained while the plant is operating under closed-loop control. So called multi-stage identification techniques are particularly useful in industrial applications where obtaining input-output information in the absence of closed-loop control is often difficult. These open-loop system models can then be employed in the design of more sophisticated closed-loop controllers. This paper introduces a methodology to identify linear open-loop models of gas turbine engines using a multi-stage identification procedure. The procedure utilizes closed-loop data to identify a closed-loop sensitivity function in the first stage and extracts the open-loop plant model in the second stage. The closed-loop data can be obtained by any sufficiently informative experiment from a plant in operation or simulation. We present simulation results here. This is the logical process to follow since using experimentation is often prohibitively expensive and unpractical. Both identification stages use standard open-loop identification techniques. We then propose a series of techniques to validate the accuracy of the identified models against first principles simulations in both the time and frequency domains. Finally, the potential to use these models for control design is discussed.

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A 19-Way Isolated Power Divider Via the TE/sub 01/ Circular Waveguide Mode Transition

10.1109/mwsym.1986.1132234 ◽

2005 ◽

Cited By ~ 4

Author(s):

M.H. Chen

Keyword(s):

Waveguide Mode ◽

Circular Waveguide ◽

Power Divider ◽

Mode Transition

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The comparison of gains prescribed for digital behind-the-ear hearing aids using the manufacturer-specific and conventional prescriptive formulas

Auditory and Vestibular Research ◽

10.18502/avr.v30i2.6097 ◽

2021 ◽

Author(s):

Shahin Shyekhaghaei ◽

Seyyed Jalal Sameni ◽

Nariman Rahbar

Keyword(s):

Hearing Loss ◽

Hearing Aids ◽

Input Output ◽

Frequency Range ◽

Sensation Level ◽

Input Intensity ◽

Multi Stage ◽

Significant Difference ◽

Different Levels ◽

Frequency Intensity

Background and Aim: There are several prescriptive formulas for covering a variety of hearing loss, each of which applies relatively different amplifications at different frequencies. This study aims to compare the gains prescribed for digital behind-the-ear (BTE) hearing aids by the Desired Sensation Level Multi-Stage [Input/Output] (DSLm[I/O]), National Acoustic Laboratories-non linear2 (NAL-NL2) and manufacturer-specific formulas at different levels of input intensity. Methods: The gain values in 12-channel BTE hearing aids prepared from four companies (Oticon, Phonak, ReSound and Siemens) were measured at three levels of input intensity (45, 65, and 85 dB SPL) and at a frequency range of 250−8000 Hz for two moderately severe flat and mild sloping to severe hearing losses by using the DSLm[I/O], NAL-NL2 and manufacturerspecific formulas in the Frye FP35 test box. Results: There was no significant difference between the four selected hearing aids in terms of prescribed gain values using the prescriptive formulas (p > 0.05). Conclusion: The DSLm[I/O] formula prescribes higher gain in the 12-channel BTE hearing aids from Oticon, Phonak and Siemens companies at all input intensities and frequencies for moderately severe flat and mild sloping to severe hearing losses compared to the NAL-NL2 formula and manufacturer-specific formulas (Voice Aligned Compression (VAC), Adaptive Phonak, Connexx Fit and audiogram+). Keywords: National acoustic laboratories-non linear2; desired sensation level multi-stage [input/output]; gain; frequency; intensity levels

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Response of silicon detecting chip to X-band electromagnetic wave modes in circular waveguide

High Power Laser and Particle Beams ◽

10.3788/hplpb20142610.103001 ◽

2014 ◽

Vol 26 (10) ◽

pp. 103001

Author(s):

王光强 Wang Guangqiang ◽

王建国 Wang Jianguo ◽

朱湘琴 Zhu Xiangqin ◽

王雪锋 Wang Xuefeng ◽

李爽 Li Shuang

Keyword(s):

Electromagnetic Wave ◽

Circular Waveguide ◽

X Band ◽

Wave Modes

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Tuning the impedance matching characteristics of microwave absorbing paint in X-band using copper particles and polypyrrole coating

Materials Research Bulletin ◽

10.1016/j.materresbull.2020.110780 ◽

2020 ◽

Vol 125 ◽

pp. 110780 ◽

Cited By ~ 1

Author(s):

Qiang Gu ◽

Mojtaba Jafarian ◽

Seyyed Salman Seyyed Afghahi ◽

Yomen Atassi ◽

Rama Al-Qassar

Keyword(s):

Impedance Matching ◽

Copper Particles ◽

X Band ◽

Microwave Absorbing

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Wideband Gysel HMSIW power divider with high power-handling capability

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078717001568 ◽

2018 ◽

Vol 10 (3) ◽

pp. 308-312

Author(s):

Kaijun Song ◽

Te Kong ◽

Yu Zhu ◽

Hongxing Xu ◽

Lifei Jiang ◽

...

Keyword(s):

High Power ◽

Reasonable Agreement ◽

Impedance Matching ◽

Power Divider ◽

Mode Analysis ◽

Analysis Method ◽

Input Output ◽

Output Impedance ◽

Power Handling ◽

Power Handling Capability

AbstractA novel Gysel power divider with high power-handling capability based on half-mode substrate integrated waveguide (HMSIW) has been presented in this paper. A HMSIW ring is used and good input/output impedance matching is achieved based on HMSIW-microstrip taper transition. Two microstrip stubs are introduced in HMSIW ring to assemble two isolation resistors to improve the isolation between the output ports. The even- and odd-mode analysis method is used for the presented circuit. A prototype of the presented power divider is designed, fabricated, and measured. The measured results show a reasonable agreement with the simulated ones.

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