Pub Date : 2022-05-09DOI: 10.1109/mms55062.2022.9825601
Ayse Müge Zobu, B. Dagdeviren, Gün Demirbaü, Bahadir Can Kocaoglu, Engin Gürhan
This paper proposes an antenna array with a feeding network to obtain low side lobe levels. The design procedure for a feeding network which uses Dolph-Tschebyscheff distributed coefficients is presented in this paper. The Dolph- Tschebyscheff coefficients has been calculated to get −20 dB side lobe level. The shunt connected series feeding network has been designed according to coefficients. By adding delay lines to the output of the feeding network, the radiation pattern of the antenna has been directed to the desired angle. It is observed that the side lobe level has been reduced to −15 dB. The proposed feeding network can help to reduce the side lobe level of linear antenna arrays.
{"title":"Low Sidelobe Level Antenna Array with Amplitude Tapering","authors":"Ayse Müge Zobu, B. Dagdeviren, Gün Demirbaü, Bahadir Can Kocaoglu, Engin Gürhan","doi":"10.1109/mms55062.2022.9825601","DOIUrl":"https://doi.org/10.1109/mms55062.2022.9825601","url":null,"abstract":"This paper proposes an antenna array with a feeding network to obtain low side lobe levels. The design procedure for a feeding network which uses Dolph-Tschebyscheff distributed coefficients is presented in this paper. The Dolph- Tschebyscheff coefficients has been calculated to get −20 dB side lobe level. The shunt connected series feeding network has been designed according to coefficients. By adding delay lines to the output of the feeding network, the radiation pattern of the antenna has been directed to the desired angle. It is observed that the side lobe level has been reduced to −15 dB. The proposed feeding network can help to reduce the side lobe level of linear antenna arrays.","PeriodicalId":124088,"journal":{"name":"2022 Microwave Mediterranean Symposium (MMS)","volume":"417 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131725083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-09DOI: 10.1109/mms55062.2022.9825590
M. Margalef-Rovira, N. Defrance, G. Ducournau
This work presents an overview of the current state-of-the-art Power Amplifiers and Low-Noise amplifiers in the 40–75 GHz frequency band (i.e., V -band). These RF blocks are critical for the development of future LEO constellations that have recently begun to target these frequencies. Special attention is brought to GaAs, GaN, SiGe, FDSOI and classical CMOS technologies. The aim of the paper is to give a clear overview of the attainable performances with each technology as well as their relative trade-offs.
{"title":"SiGe Circuits for Future LEO Constellations","authors":"M. Margalef-Rovira, N. Defrance, G. Ducournau","doi":"10.1109/mms55062.2022.9825590","DOIUrl":"https://doi.org/10.1109/mms55062.2022.9825590","url":null,"abstract":"This work presents an overview of the current state-of-the-art Power Amplifiers and Low-Noise amplifiers in the 40–75 GHz frequency band (i.e., V -band). These RF blocks are critical for the development of future LEO constellations that have recently begun to target these frequencies. Special attention is brought to GaAs, GaN, SiGe, FDSOI and classical CMOS technologies. The aim of the paper is to give a clear overview of the attainable performances with each technology as well as their relative trade-offs.","PeriodicalId":124088,"journal":{"name":"2022 Microwave Mediterranean Symposium (MMS)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134288673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-09DOI: 10.1109/mms55062.2022.9825522
Stela Furxhi, Simone De Marzi, R. Giofré, P. Colantonio
This work discusses the design and the expected results of two stacked-cells implemented in a $0.15 mu mathrm{m}$ gate-length Gallium Nitride (GaN) Monolithic Microwave Integrated Circuit (MMIC) technology for K-band power applications. Both cells are based on the same overall active periphery but one exploits a self-bias (SeB) approach for the common gate device, whereas the other is biased on a more traditional independent bias routing (SaB). Moreover, with respect to the traditional approach, in both cells the common source device is split in two in order to reduce the parasitic contribution and also to obtain a more compact and easy to implement overall stacked cell. The main goal of this paper is to provide a fair comparison between SeB and SaB stacked cells, by highlighting pros and cons of both approaches in terms of linear and nonlinear performances.
本工作讨论了两个堆叠单元的设计和预期结果，实现在$0.15 mu mathrm{m}$门长氮化镓(GaN)单片微波集成电路(MMIC)技术中，用于k波段功率应用。两个单元都基于相同的整体有源外围，但其中一个利用自偏置(SeB)方法用于公共栅极器件，而另一个则采用更传统的独立偏置路由(SaB)。此外，与传统方法相比，在两个单元中，为了减少寄生贡献，也为了获得更紧凑和易于实现的整体堆叠单元，公共源器件被分成两部分。本文的主要目标是通过突出两种方法在线性和非线性性能方面的优缺点，提供SeB和SaB堆叠单元之间的公平比较。
{"title":"GaN Stacked Cells for Power Applications in K-Band: A Comparative Study","authors":"Stela Furxhi, Simone De Marzi, R. Giofré, P. Colantonio","doi":"10.1109/mms55062.2022.9825522","DOIUrl":"https://doi.org/10.1109/mms55062.2022.9825522","url":null,"abstract":"This work discusses the design and the expected results of two stacked-cells implemented in a $0.15 mu mathrm{m}$ gate-length Gallium Nitride (GaN) Monolithic Microwave Integrated Circuit (MMIC) technology for K-band power applications. Both cells are based on the same overall active periphery but one exploits a self-bias (SeB) approach for the common gate device, whereas the other is biased on a more traditional independent bias routing (SaB). Moreover, with respect to the traditional approach, in both cells the common source device is split in two in order to reduce the parasitic contribution and also to obtain a more compact and easy to implement overall stacked cell. The main goal of this paper is to provide a fair comparison between SeB and SaB stacked cells, by highlighting pros and cons of both approaches in terms of linear and nonlinear performances.","PeriodicalId":124088,"journal":{"name":"2022 Microwave Mediterranean Symposium (MMS)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132055795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-09DOI: 10.1109/mms55062.2022.9825544
A. Morini, M. Farina, M. Guglielmi, P. M. Iglesias, P. Angeletti
The Generalized Reflect Thru Line (GTRL) calibration technique is used for the measurement of a waveguide devices operating in a multioctave band region. In this contribution some preliminary results are shown concerning measurements done up to the third harmonic, where up to four modes are above cutoff.
{"title":"Generalized Thru-Reflect-Line Calibration for the Measurement of Waveguide Devices up to the third Harmonic: First Results","authors":"A. Morini, M. Farina, M. Guglielmi, P. M. Iglesias, P. Angeletti","doi":"10.1109/mms55062.2022.9825544","DOIUrl":"https://doi.org/10.1109/mms55062.2022.9825544","url":null,"abstract":"The Generalized Reflect Thru Line (GTRL) calibration technique is used for the measurement of a waveguide devices operating in a multioctave band region. In this contribution some preliminary results are shown concerning measurements done up to the third harmonic, where up to four modes are above cutoff.","PeriodicalId":124088,"journal":{"name":"2022 Microwave Mediterranean Symposium (MMS)","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121425155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-09DOI: 10.1109/mms55062.2022.9825570
A. Mahmoud, M. Del Mastro, T. Potelon, R. Sauleau, M. Ettorre
A low-profile antenna for satellite communications (SatCom) applications is presented here. The antenna covers the entire K/Ka frequency bands from 19 GHz to 31 GHz with a reflection coefficient better than −10 dB, corresponding to a relative bandwidth of more than 50%. A continuous transverse stub (CTS) antenna array is chosen as a radiating aperture for its very wideband performance. The radiating aperture is fed by a pillbox quasi-optical beamformer. The full antenna is realized in printed circuit board (PCB) technology by stacking several dielectric layers without any buried or blind vias in the full stack-up. Multiple horns are placed along the focal plane of the pillbox coupler to achieve beam-scanning in elevation. ± 25°. The peak value of the realized gain is 19 dBi and radiation efficiency equals 50%.
{"title":"Mutli-layer CTS antenna array in PCB technology for SatCom applications","authors":"A. Mahmoud, M. Del Mastro, T. Potelon, R. Sauleau, M. Ettorre","doi":"10.1109/mms55062.2022.9825570","DOIUrl":"https://doi.org/10.1109/mms55062.2022.9825570","url":null,"abstract":"A low-profile antenna for satellite communications (SatCom) applications is presented here. The antenna covers the entire K/Ka frequency bands from 19 GHz to 31 GHz with a reflection coefficient better than −10 dB, corresponding to a relative bandwidth of more than 50%. A continuous transverse stub (CTS) antenna array is chosen as a radiating aperture for its very wideband performance. The radiating aperture is fed by a pillbox quasi-optical beamformer. The full antenna is realized in printed circuit board (PCB) technology by stacking several dielectric layers without any buried or blind vias in the full stack-up. Multiple horns are placed along the focal plane of the pillbox coupler to achieve beam-scanning in elevation. ± 25°. The peak value of the realized gain is 19 dBi and radiation efficiency equals 50%.","PeriodicalId":124088,"journal":{"name":"2022 Microwave Mediterranean Symposium (MMS)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128845411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-09DOI: 10.1109/mms55062.2022.9825622
M. Barbuto, A. Alú, F. Bilotti, A. Toscano
Reconfigurability is a key property of modern communication systems, which need to adapt in real-time to changing environments and different operative conditions. Although several approaches to tailor the response of an electromagnetic system have been proposed, the quest for a complete and simple reconfigurable strategy is still far to be solved. Indeed, the possibility to tailor the response of the system typically involves a huge number of control lines and, thus, some critical issues for the practical implementation of the final design. In this framework, we discuss here the possibility of exploiting composite vortex theory for manipulating the response of reflective and radiating systems. In particular, by acting on a limited number of knobs, i.e. the relative amplitude and phase of two superimposed vortex modes, we show that both the radiating properties of patch antennas and the scattering pattern of reflective surfaces can be easily controlled.
{"title":"Designing Reconfigurable Reflective and Radiating Structures by Exploiting Composite Vortex Theory","authors":"M. Barbuto, A. Alú, F. Bilotti, A. Toscano","doi":"10.1109/mms55062.2022.9825622","DOIUrl":"https://doi.org/10.1109/mms55062.2022.9825622","url":null,"abstract":"Reconfigurability is a key property of modern communication systems, which need to adapt in real-time to changing environments and different operative conditions. Although several approaches to tailor the response of an electromagnetic system have been proposed, the quest for a complete and simple reconfigurable strategy is still far to be solved. Indeed, the possibility to tailor the response of the system typically involves a huge number of control lines and, thus, some critical issues for the practical implementation of the final design. In this framework, we discuss here the possibility of exploiting composite vortex theory for manipulating the response of reflective and radiating systems. In particular, by acting on a limited number of knobs, i.e. the relative amplitude and phase of two superimposed vortex modes, we show that both the radiating properties of patch antennas and the scattering pattern of reflective surfaces can be easily controlled.","PeriodicalId":124088,"journal":{"name":"2022 Microwave Mediterranean Symposium (MMS)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129047169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-09DOI: 10.1109/mms55062.2022.9825614
P. Njogu, B. Sanz-Izquierdo, S. Jun, Zhijiao Chen, S. Gao
A 3D printed antenna embedded in a 3D printed ring for 5G millimeter wave applications is proposed. Two additive manufacturing (AM) methods have been combined in a single machine to develop the structure. Fused filament fabrication (FFF) was used to make the substrate of the antenna and supporting ring while direct write with conductive paste was used to create the antenna radiator. Polylactic acid (PLA) plastic was used in the development of the dielectric layers while the metallic patch of the radiator was created using silver paste. Reflection coefficient and radiation pattern of the ring antenna were tested in free space and worn on a hand phantom. The hand phantom was developed using pork sausages placed inside a thin glove. The design and simulations were carried out in CST Microwave StudioTM. Measured results show consistency with the simulated results. The antenna operates satisfactorily at the proposed 5G millimeter wave communication band. This work aims to demonstrate a concept of millimeter wave 3D printed ring antennas and the development and use of sausage-based hand phantoms for antenna measurements.
{"title":"3D Printed Millimeter wave Antenna Integrated into a Ring for 5G Applications","authors":"P. Njogu, B. Sanz-Izquierdo, S. Jun, Zhijiao Chen, S. Gao","doi":"10.1109/mms55062.2022.9825614","DOIUrl":"https://doi.org/10.1109/mms55062.2022.9825614","url":null,"abstract":"A 3D printed antenna embedded in a 3D printed ring for 5G millimeter wave applications is proposed. Two additive manufacturing (AM) methods have been combined in a single machine to develop the structure. Fused filament fabrication (FFF) was used to make the substrate of the antenna and supporting ring while direct write with conductive paste was used to create the antenna radiator. Polylactic acid (PLA) plastic was used in the development of the dielectric layers while the metallic patch of the radiator was created using silver paste. Reflection coefficient and radiation pattern of the ring antenna were tested in free space and worn on a hand phantom. The hand phantom was developed using pork sausages placed inside a thin glove. The design and simulations were carried out in CST Microwave StudioTM. Measured results show consistency with the simulated results. The antenna operates satisfactorily at the proposed 5G millimeter wave communication band. This work aims to demonstrate a concept of millimeter wave 3D printed ring antennas and the development and use of sausage-based hand phantoms for antenna measurements.","PeriodicalId":124088,"journal":{"name":"2022 Microwave Mediterranean Symposium (MMS)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115936493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-09DOI: 10.1109/mms55062.2022.9825569
Rahul Yadav, S. Preu, A. Penirschke
Terahertz (THz) domain is quickly developing with various applications such as beam diagnostics at particle accelerators, spectroscopy, communications, space science, etc. However, often requiring fast intermediate frequency (IF) electronics. We present the design of a double mirror stub (DMS) based a planar broadband bias tee having an isolation port S31 with 14.45 GHz bandwidth below −10 dB and S33 with 13.1 GHz bandwidth above −2 dB. CST simulation and measured results are in very good agreement. The bias tee will be a part of a new generation of on-chip THz detectors based on zero-bias Schottky diode and high electron mobility field effect transistor (HEMT).
{"title":"A Double Mirror Stub Design of Broadband Planar Bias Tee for System on Chip Integration","authors":"Rahul Yadav, S. Preu, A. Penirschke","doi":"10.1109/mms55062.2022.9825569","DOIUrl":"https://doi.org/10.1109/mms55062.2022.9825569","url":null,"abstract":"Terahertz (THz) domain is quickly developing with various applications such as beam diagnostics at particle accelerators, spectroscopy, communications, space science, etc. However, often requiring fast intermediate frequency (IF) electronics. We present the design of a double mirror stub (DMS) based a planar broadband bias tee having an isolation port S31 with 14.45 GHz bandwidth below −10 dB and S33 with 13.1 GHz bandwidth above −2 dB. CST simulation and measured results are in very good agreement. The bias tee will be a part of a new generation of on-chip THz detectors based on zero-bias Schottky diode and high electron mobility field effect transistor (HEMT).","PeriodicalId":124088,"journal":{"name":"2022 Microwave Mediterranean Symposium (MMS)","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117174036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-09DOI: 10.1109/mms55062.2022.9825589
S. Kılınç, Malik Ehsan Ejaz, S. Yarman, S. Ozoguz, S. Srivastava, Edmond Nurellari
Generation of proper source/load pull impedances for a selected active device is essential to design an RF power amplifier for optimum gain and power added efficiency. As they are obtained, these impedances may not be realizable network functions over the desired frequency band to yield the input and the output matching networks for the amplifier. Therefore, in this paper, we introduce a useful method to test if the generated source and load pull data are realizable. The proposed technique is employed to test the given source and load pull impedance data obtained from the 45W-GaN power transistor of Wolfspeed “CG2H40045” over 0.8-3.8 GHz bandwidth.
{"title":"A Realizability Test as Applied on the Generated Source/Load-Pull Data","authors":"S. Kılınç, Malik Ehsan Ejaz, S. Yarman, S. Ozoguz, S. Srivastava, Edmond Nurellari","doi":"10.1109/mms55062.2022.9825589","DOIUrl":"https://doi.org/10.1109/mms55062.2022.9825589","url":null,"abstract":"Generation of proper source/load pull impedances for a selected active device is essential to design an RF power amplifier for optimum gain and power added efficiency. As they are obtained, these impedances may not be realizable network functions over the desired frequency band to yield the input and the output matching networks for the amplifier. Therefore, in this paper, we introduce a useful method to test if the generated source and load pull data are realizable. The proposed technique is employed to test the given source and load pull impedance data obtained from the 45W-GaN power transistor of Wolfspeed “CG2H40045” over 0.8-3.8 GHz bandwidth.","PeriodicalId":124088,"journal":{"name":"2022 Microwave Mediterranean Symposium (MMS)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115458419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-09DOI: 10.1109/mms55062.2022.9825573
I. Marasco, G. Niro, F. Rizzi, A. D’orazio, M. de Vittorio, M. Grande
Planar Inverted-F antennas (PIFAs), due to their planar topology and compact dimensions combined with multi-band working frequencies, are becoming increasingly popular in the scientific community and the technology industry places so much emphasis on them. The design and the fabrication of PIFAs on innovative substrates become crucial to facilitate their integration in wireless sensor network systems and to enhance the connectivity of Internet of Healthcare Things (IoHT) network nodes. In this work we propose the fabrication and characterization of a compact (13×26 mm2) PIF A placed on a flexible 250 um-thick Polyethylene Naphthalate (PEN) substrate working in both the sub-6GHz and 6GHz bands of 5G spectrum. The antenna has been realized by means of a multi-material 3D printer, NanoDimension's Dragonfly LTM. The use of the 3D printer entails the rapid prototyping and increases the scalability of the process.
{"title":"Dual band flexible Planar Inverted-F antenna for Internet of Healthcare Things applications","authors":"I. Marasco, G. Niro, F. Rizzi, A. D’orazio, M. de Vittorio, M. Grande","doi":"10.1109/mms55062.2022.9825573","DOIUrl":"https://doi.org/10.1109/mms55062.2022.9825573","url":null,"abstract":"Planar Inverted-F antennas (PIFAs), due to their planar topology and compact dimensions combined with multi-band working frequencies, are becoming increasingly popular in the scientific community and the technology industry places so much emphasis on them. The design and the fabrication of PIFAs on innovative substrates become crucial to facilitate their integration in wireless sensor network systems and to enhance the connectivity of Internet of Healthcare Things (IoHT) network nodes. In this work we propose the fabrication and characterization of a compact (13×26 mm2) PIF A placed on a flexible 250 um-thick Polyethylene Naphthalate (PEN) substrate working in both the sub-6GHz and 6GHz bands of 5G spectrum. The antenna has been realized by means of a multi-material 3D printer, NanoDimension's Dragonfly LTM. The use of the 3D printer entails the rapid prototyping and increases the scalability of the process.","PeriodicalId":124088,"journal":{"name":"2022 Microwave Mediterranean Symposium (MMS)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115593309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：