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Design,fabrication,and cold test of an s-band high-gradient accelerating structure for compact proton therapy facility

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Nuclear science and Techniques 2021年第4期32卷 38-48页

作者： Yu Zhang Wen-Cheng Fang Xiao-Xia Huang Jian-Hao Tan Cheng Wang Chao-Peng Wang Zhen-Tang Zhao shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of sciences Beijing 100049China shanghaiTech University Shanghai 201210China shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

An s-band high-gradient accelerating structure is designed for a proton therapy linear accelerator(linac)to accommodate the new development of compact,singleroom facilities and ultra-high dose rate(FLAsH)*** optimize the design,an efficient optimization scheme is applied to improve the simulation *** s-band accelerating structure with 2856 MHz is designed with a low beta of 0.38,which is a difficult structure to achieve for a linac accelerating proton particles from 70 to 250 MeV,as a high gradient up to 50 MV/m is required.A special design involving a dual-feed coupler eliminates the dipole field *** paper presents all the details pertaining to the design,fabrication,and cold test results of the s-band high-gradient accelerating structure.

关键词： s-band High gradient Accelerating structure Compact single-room facility Dual-feed coupler Cold test

Design of broadband class-F power amplifier with high-order harmonic suppression for s-band application

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Journal of semiconductors 2015年第12期36卷 119-123页

作者：林俊明章国豪郑耀华李思臻张志浩陈思弟 Guangdong University of Technology

A broadband class-F power amplifier for an s-band handset device is integrated on a 330.82 mm^3 die using an In Ga /GaAs HBT process. With LC serial harmonic traps immersed into the broadband output matching circuit, good harmonic suppression performance can be achieved. A pure resistive impedance of the matching circuit, but near zero at second and infinite at third harmonic frequency, which enhances the efficiency, is obtained across 1.8–2.5 GHz. Tested with a continuous wave（CW） signal, the PA delivers an output power of 34 dBm and achieves a PAE of 57% at 2 GHz. In addition, excellent harmonic suppression levels of less than –53 dBc across the second to fifth harmonic are obtained.

关键词： s-band power amplifier broadband class-F harmonic suppression InGaP/GaAs HBT

RF design of an s-band spherical cavity pulse compressor

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Radiation Detection Technology and Methods 2017年第2期1卷 57-64页

作者： Jie Lei Xiang He Mi Hou Guan shu Guo-Xi Pei Xiao-Ping Li Hui Wang Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of science Beijing 100049China

The pulse compressor plays an important role in accelerators by enhancing the RF peak *** s-band(2856 MHz)spherical cavity pulse compressor consisting of a special 3 dB coupler and a single spherical energy storage cavity has been developed in Institute of High Energy *** special 3 dB coupler converts the TE10 mode in rectangular waveguide to two polarization degenerated TE11 modes in cylindrical *** is also a circular polarizer and its general scattering matrix is given for the first *** magnitude and the phase difference of the two TE11 modes are−3.016,−3.005 dB and 90.02◦in HFss,while it is−3.01,−3.01 dB and 89.79◦in *** simulated s parameters show agreement with the general scattering *** TE114 mode with an unloaded Q factor of 190,000 has been chosen to resonate in the spherical *** energy multiplication factor of 1.75 and a peak power gain of 5.75 were obtained for the whole pulse compressor,which agrees with the design requirements.A good pulse compression performance is also proved by the CsT time-domain *** addition,the scheme for tuning and detuning is designed and given in *** to the traditional sLED type,the spherical cavity pulse compressor uses only one spherical cavity to realize the pulse compression,which makes it compact as a whole.

关键词： s-band 3 dB coupler spherical storage cavity Pulse compressor Circular polarizer

Design and cold test of an s-band waveguide dual circular polarizer

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Radiation Detection Technology and Methods 2017年第2期1卷 117-123页

作者： Jie Lei Xiang He Guo-Xi Pei Mi Hou Hui Wang Jian-Bing Zhao Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of sciences Beijing 100049China

Purpose An s-band dual circular polarizer has been designed and tested with low power in the paper,which will be applied in a spherical cavity pulse *** converts the TE10 mode in rectangular waveguide into two polarization degenerated TE11 modes in cylindrical *** The general scattering matrix of the dual circular polarizer has been deduced based on the properties of the passive microwave network,which is suitable for the usual 3 dB coupler,as well as the left/right hand circular *** on the 3D code software CsT,the dual circular polarizer was numerically ***,two prototypes have been manufactured and tested with the vector network analyzer(VNA).Results The simulation results show that the magnitudes and phase difference of the two TE11 modes are dB and 89.79 degrees,*** cold test results show good agreement with CsT simulation.−3.0103/−3.0104 Conclusion The method of analyzing the relationship between the voltage standing wave ratio(VsWR)and the errors of the magnitudes and phase difference of the two TE11 modes was given,which can be used to qualitatively analyze the properties of the circular *** s-band waveguide dual circular polarizer can be applied in the pulse compressor,phase shifter or other frequency bands.

关键词： s-band Dual circular polarizer scattering matrix Pulse compressor Phase shifter

Radio-frequency design and commissioning of a flexible waveguide for high-vacuum s-band applications

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Radiation Detection Technology and Methods 2020年第2期4卷 250-254页

作者： Xiang He Jian-she Cao Bing-Lin Deng Jing-Dong Liu Nan Gan Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

Purpose Flexible waveguides,which allow for greater deformation as compared to traditional hard waveguides,are highly useful for simplifying waveguide system ***,the peak powers of these waveguides have been limited to several megawatts in non-vacuum ***,a novel flexible waveguide was developed for the s-band(2856 MHz)with the aim of facilitating the interconnection of two hard *** The flexible waveguide was composed of brass,and its surface was plated with oxygen-free high-conductivity copper for brazing with stainless steel flanges in a vacuum *** connecting the stainless steel flanges together,it can be applied to a high-vacuum *** The prototype exhibited good measurement results in low-power microwave tests;the results of a 72-h vacuum leak test showed satisfactory vacuum performance as well,and no obvious surface collapse was ***-power microwave commissioning was conducted between June and July 2019;the waveguide showed a maximum average power of approximately 2.7 *** Unfortunately,the prototype was damaged after reaching that power level,which indicates the need for further optimization of the fabrication *** our experiment,it is clear that the flexible waveguide cannot be used in large accelerators because of its average power limit.

关键词： s-band Flexible waveguide High vacuum Microwave commissioning

suppression of Log-Normal Distributed Weather Clutter Observed by an s-band Radar

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Wireless Engineering and Technology 2013年第3期4卷 125-133页

作者： shuji sayama seishiro Ishii Department of Communications Engineering National Defense Academy Yokosuka Japan Department of Information Networks Sendai National College of Technology Sendai Japan.

We have observed weather clutter containing targets (ships) using an s-band radar with a frequency 3.05 GHz, a beam width 1.8°, and a pulsewidth 0.5 μs. To investigate the weather clutter amplitude statistics, we introduce the Akaike Information Criterion (AIC). We have found that the weather clutter amplitudes obey the log-normal, Weibull, and log-Weibull distributions with the shape parameters of 0.308 to 0.470, 4.42 to 4.51, and 15.91 to 16.44, respectively, for small data within the beam width of an antenna. We have proposed the log-normal/CFAR circuit modified a Cell-Averaging (CA) LOG/CFAR circuit. It is found that weather clutter is suppressed with improvement of 51.58 dB by log-normal/CFAR. As a result, we have showed that weather clutter observed by s-band radar does not obey the Rayleigh distribution and our log-normal/CFAR circuit has an effect on suppression of clutter and detection of target, while conventional LOG/CFAR circuit does not. In addition, if our circuit can be realized, we will have an advantage economically.

关键词： CFAR s-band Radar Weather Clutter Log-Normal Distribution

study on MsK modulation for s-band

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Study on MSK modulation for S-band

Design and Modeling of s band Circular Patch and Ka band Horn Antenna, Integration with Future Multifunctional Radio over Fiber Network

第四届中国卫星导航学术年会

作者： Wang Fengjiao Li Rui, Zeng Dazhi school of Information and Electronics Beijing Institute of Technology

With the development of global navigation satellite system （GNss）, the number of signals transmitted in L-band has been increasing. Exploiting new frequency bands for radio navigation satellite service （RNss） is quite necessary. s-band has received widely attention since the performance of positioning and timing will be benefited significantly by joint positioning of s-band and L-band. The minimum shift keying-binary offset carrier （MsK-BOC） modulation was proposed to be used for Beidou-2 s-band here. The compatibility between Beidou-2 and Beidou-1/Globalstar system was firstly evaluated, and then signal’s code tracking error and multipath error envelope were analyzed. Results indicate that the performance in terms of compatibility and tracking precision of MsK-BOC modulation in s-band is good. The research will provide an instructive reference for the signal design and engineering implementation of Beidou-2.

关键词： s-band MsK modulation compatibility interference code tracking precision

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Open Journal of Antennas and Propagation 2017年第3期5卷 121-131页

作者： Rao Kashif Oluwole John Famoriji Fujiang Lin Department of Electronic science and Technology University of Science and Technology of China Anhui China

Radio over Fiber is an integration of microwave and optical fiber technologies having numerous benefits. RoF technology can give a scope of advantages including the capacity for backing multiple radio services and standards. In coming future, there is need of integrated wireless service with high speed satellite broadband and multifunctional indoor/outdoor antennas. Radio over fiber is one of the most favorite candidates to meet all these requirements of future multifunctional integrated wireless communication. Due to planer profile, small size and low cost patch antennas are most favorite to use for multi- frequency applications. In this paper, we present system level design for future multifunctional radio over fiber network. Under FTTH (Fiber To The Home) technology, it will be possible to use multi-frequency applications on single fiber medium. Firstly, we designed s band circular patch antenna (2.5 GHz) and Ka band (29 GHz) horn antenna. Circular patch antenna performance is estimated with different substrate height. After getting s parameters and far-field results, we did modeling of Radio over Fiber system over (10 Km) with same parameters from antenna results.

关键词： Radio over Fiber s-band Ka-band March Zehnder Modulator CW Laser

Double-E-Triple-H-shaped NRI-Metamaterial for Dual-band Microwave sensing Applications

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Computers, Materials & Continua 2022年第6期71卷 5817-5836页

作者： shafayat Hossain Md.Iquebal Hossain Patwary sikder sunbeam Islam sultan Mahmud Norbahiah Binti Misran Ali F.Almutairi Mohammad Tariqul Islam Department of Electrical&Electronics Engineering International Islamic University Chittagong4318ChittagongBangladesh Department of Electrical Electronic and Systems EngineeringFaculty of Engineering and Built EnvironmentUniversiti Kebangsaan MalaysiaBangiSelangor43600Malaysia Electrical Engineering Department Kuwait UniversityKuwait City13060Kuwait

This paper presents a new Double-E-Triple-H-shaped NRI(negative refractive index)metamaterial(MM)for dual-band microwave sensing ***,a horizontal H-shaped metal structure is enclosed by two face-to-face E-shaped metal *** double-E-H-shaped design is also encased by two vertical H-shaped structures along with some copper ***,the Double-E-Triple-H-shaped configuration is *** popular substrate materials of Rogers RO 3010 and FR-4 were adopted for analyzing the characteristics of the unit *** proposed structure exhibits transmission resonance inside the s-band with NRI and ENG(Epsilon Negative)metamaterial properties,and inside the C-band with ENG and MNG(Mu Negative)metamaterial properties.A good effective medium ratio(EMR)of 8.06 indicates the compactness and effectiveness of the proposed *** analysis has been done by changing the thickness of the substrate material as well and a significant change in the effective medium ratio is *** validity of the proposed structure is confirmed by an equivalent circuit *** simulated result agrees well with the calculated *** exploring microwave sensing applications of the proposed unit cell,permittivity and pressure sensitivity performance were investigated in different simulation *** compact size,effective parameters,high sensitivity and a good EMR represent the proposed metamaterial as a promising solution for s-band and C-band microwave sensing applications.

关键词： Metamaterial NRI MNG ENG dual-band sensing s-band C-band