Pub Date : 2020-07-05DOI: 10.1109/IEEECONF35879.2020.9329715
Shaker Alkaraki, J. Kelly, C. Parini, Yue Gao, S. Stremsdoerfer, E. Gayets
This paper presents a 3D printed antenna for X-band applications. The antenna is compact and it has high measured gain performance with high aperture efficiency over wide bandwidth covers 5 GHz. The proposed antenna consists of two layers stacked on top of each other, where the top layer is the radiating structure. The radiating structure consists of central slots surrounded by corrugations and cavity to improve the gain of the antenna. The proposed antenna is directive, compact and with high aperture efficiency performance. The antenna has a peak measured gain of 18.7 dBi at 11.3 GHz with a peak aperture efficiency of 56.6%.
{"title":"High Gain 3D Printed Antenna with Corrugations and High Aperture Efficiency Performance","authors":"Shaker Alkaraki, J. Kelly, C. Parini, Yue Gao, S. Stremsdoerfer, E. Gayets","doi":"10.1109/IEEECONF35879.2020.9329715","DOIUrl":"https://doi.org/10.1109/IEEECONF35879.2020.9329715","url":null,"abstract":"This paper presents a 3D printed antenna for X-band applications. The antenna is compact and it has high measured gain performance with high aperture efficiency over wide bandwidth covers 5 GHz. The proposed antenna consists of two layers stacked on top of each other, where the top layer is the radiating structure. The radiating structure consists of central slots surrounded by corrugations and cavity to improve the gain of the antenna. The proposed antenna is directive, compact and with high aperture efficiency performance. The antenna has a peak measured gain of 18.7 dBi at 11.3 GHz with a peak aperture efficiency of 56.6%.","PeriodicalId":135770,"journal":{"name":"2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128188159","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 : 2020-07-05DOI: 10.1109/IEEECONF35879.2020.9329969
H. Abedi, G. Shaker
Extensive research has been conducted on millimeter wave (mm-wave) chipset solutions led to reduction in size and cost while adding sensitivity and accuracy. Recent 79GHz chipset solutions using antenna-in package approach were developed for various applications with a wide beamwidth and low gain. However, for some applications such as multiple people vital sings detection and corridor gait monitoring, there is still a need to achieve higher gain with thinner beamwidth, to increase the signal-to-noise ratio (SNR) and the transmit/receive range of the system, mitigate the reflection from surrounding objects as well as reduce multi-path effects. The use of a lens is an appealing solution since it could improve the system performances while using existing chipset solution. Using low cost and rapid manufacturing 3D printing technology, we designed and fabricated a dielectric lens antenna for a 79GHz MIMO radar. Compared with the system without lens, the full-wave simulation demonstrated a 14dB improvement in gain which is in good agreement with measurement results.
{"title":"Low-Cost 3D printed Dielectric Hyperbolic Lens Antenna for Beam Focusing and Steering of a 79GHz MIMO Radar","authors":"H. Abedi, G. Shaker","doi":"10.1109/IEEECONF35879.2020.9329969","DOIUrl":"https://doi.org/10.1109/IEEECONF35879.2020.9329969","url":null,"abstract":"Extensive research has been conducted on millimeter wave (mm-wave) chipset solutions led to reduction in size and cost while adding sensitivity and accuracy. Recent 79GHz chipset solutions using antenna-in package approach were developed for various applications with a wide beamwidth and low gain. However, for some applications such as multiple people vital sings detection and corridor gait monitoring, there is still a need to achieve higher gain with thinner beamwidth, to increase the signal-to-noise ratio (SNR) and the transmit/receive range of the system, mitigate the reflection from surrounding objects as well as reduce multi-path effects. The use of a lens is an appealing solution since it could improve the system performances while using existing chipset solution. Using low cost and rapid manufacturing 3D printing technology, we designed and fabricated a dielectric lens antenna for a 79GHz MIMO radar. Compared with the system without lens, the full-wave simulation demonstrated a 14dB improvement in gain which is in good agreement with measurement results.","PeriodicalId":135770,"journal":{"name":"2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121789135","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 : 2020-07-05DOI: 10.1109/IEEECONF35879.2020.9330347
Meng Guo, Wei Wang, Jing Wang, Yuchen Tong
During the vehicle millimeter-wave radar application, the envelope signal would be continuously reflected between the bumper and radar, which causes the misjudgment in the direction of arrival (DoA). Thereby it is essential to improve the resolution through scattering the reflected envelope signal. Assuming the bumper installed in front of the radar, then the key of resolution enhancement resides in the backward scattering, or to say, the monostatic radar cross-section (RCS) reduction. This paper presents a hollow substrate with square unit cells, which form an artificial magnetic conductor (AMC) combining with the grounded substrate. Notably based on the array, we shaped the empty part for RCS reduction, also for low side-lobe.
{"title":"Low Side-lobe, RCS Reduction Microstrip Antenna Array for 24 GHz Vehicle Millimetre Wave Radar","authors":"Meng Guo, Wei Wang, Jing Wang, Yuchen Tong","doi":"10.1109/IEEECONF35879.2020.9330347","DOIUrl":"https://doi.org/10.1109/IEEECONF35879.2020.9330347","url":null,"abstract":"During the vehicle millimeter-wave radar application, the envelope signal would be continuously reflected between the bumper and radar, which causes the misjudgment in the direction of arrival (DoA). Thereby it is essential to improve the resolution through scattering the reflected envelope signal. Assuming the bumper installed in front of the radar, then the key of resolution enhancement resides in the backward scattering, or to say, the monostatic radar cross-section (RCS) reduction. This paper presents a hollow substrate with square unit cells, which form an artificial magnetic conductor (AMC) combining with the grounded substrate. Notably based on the array, we shaped the empty part for RCS reduction, also for low side-lobe.","PeriodicalId":135770,"journal":{"name":"2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115855368","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 : 2020-07-05DOI: 10.1109/IEEECONF35879.2020.9329734
Junda Ye, Siyu Lin
The Finite State Markov Channel (FSMC) has been commonly adopted in wireless communication system optimization and protocol design, as it provides a simple mathematical processing for the performance analysis. While the literature about FSMC modeling in time domain are abundant, FSMC models describing channel fading in frequency domain are few and lack the support of measurements. In this paper, we develop an FSMC model for the vehicular channel based on real field measurements obtained from Beijing-Tianjin highway scenario. We discuss the varieties of the steady state probability and temporary skip probability in different locations. The conclusion of this paper can be used in the future FSMC modeling in frequency domain.
有限状态马尔可夫信道(Finite State Markov Channel, FSMC)为无线通信系统的性能分析提供了一种简单的数学处理方法，在无线通信系统优化和协议设计中被广泛采用。虽然时域FSMC建模的文献很多，但在频域描述信道衰落的FSMC模型很少，而且缺乏测量的支持。本文基于京津高速公路现场实测数据，建立了车辆通道的FSMC模型。讨论了稳态概率和暂跳概率在不同位置的变化。本文的结论可为未来的FSMC频域建模提供参考。
{"title":"Finite State Markov Modeling of Wideband Vehicular Channel","authors":"Junda Ye, Siyu Lin","doi":"10.1109/IEEECONF35879.2020.9329734","DOIUrl":"https://doi.org/10.1109/IEEECONF35879.2020.9329734","url":null,"abstract":"The Finite State Markov Channel (FSMC) has been commonly adopted in wireless communication system optimization and protocol design, as it provides a simple mathematical processing for the performance analysis. While the literature about FSMC modeling in time domain are abundant, FSMC models describing channel fading in frequency domain are few and lack the support of measurements. In this paper, we develop an FSMC model for the vehicular channel based on real field measurements obtained from Beijing-Tianjin highway scenario. We discuss the varieties of the steady state probability and temporary skip probability in different locations. The conclusion of this paper can be used in the future FSMC modeling in frequency domain.","PeriodicalId":135770,"journal":{"name":"2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115984062","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 : 2020-07-05DOI: 10.1109/IEEECONF35879.2020.9329878
Brian Guiana, A. Zadehgol
A 1D Gaussian expression is derived and used as the 1D E/H incident field in the TF/SF formulation to efficiently generate plane waves in 1D, 2D, and 3D FDTD simulations. The analytic expression is simple, and it eliminates the need for computational resources to store and compute the E/H-field incident arrays and their associated absorbing boundaries. FDTD simulation results at the magic time-step in 1D, 2D, and 3D FDTD show good correlation between plane waves generated by the 1D analytic Gaussian function vs. those generated by 1D FDTD incident arrays.
{"title":"A 1D Gaussian Function for Efficient Generation of Plane Waves in 1D, 2D, and 3D FDTD","authors":"Brian Guiana, A. Zadehgol","doi":"10.1109/IEEECONF35879.2020.9329878","DOIUrl":"https://doi.org/10.1109/IEEECONF35879.2020.9329878","url":null,"abstract":"A 1D Gaussian expression is derived and used as the 1D E/H incident field in the TF/SF formulation to efficiently generate plane waves in 1D, 2D, and 3D FDTD simulations. The analytic expression is simple, and it eliminates the need for computational resources to store and compute the E/H-field incident arrays and their associated absorbing boundaries. FDTD simulation results at the magic time-step in 1D, 2D, and 3D FDTD show good correlation between plane waves generated by the 1D analytic Gaussian function vs. those generated by 1D FDTD incident arrays.","PeriodicalId":135770,"journal":{"name":"2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113937638","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 : 2020-07-05DOI: 10.1109/IEEECONF35879.2020.9330359
Qiang Sun, Y. Ban, Ji-wei Lian, Xiao-Fei Li
A new array formation method for millimeter-wave (mm-wave) transverse slot scanning array antenna is proposed, which can effectively solve the grating lobes problem caused by the traditional array formation method. To verify the array formation method, a mm-wave scanning array antenna at 30GHz is designed, which consists of a traditional substrate integrated waveguide (SIW) 4 x 4 Butler Matrix (BM) feed network and 16 transverse slot elements. The distance between adjacent transverse slot elements is equal to half waveguide wavelength, and the transverse slot array antenna uses the metal cylinder matching method to improve the effective bandwidth of the array antenna, a −10dB impedance bandwidth (BW) of scanning array antenna from 28.9 to 31.04 GHz is simulated. The peak broadside gain of the array antenna is 13.7dB. This type of transverse slot scanning array antenna will have many applications in the future 5G mm-wave band.
{"title":"A New Array Formation Method for Millimeter-wave Transverse Slot Scanning Array Antenna","authors":"Qiang Sun, Y. Ban, Ji-wei Lian, Xiao-Fei Li","doi":"10.1109/IEEECONF35879.2020.9330359","DOIUrl":"https://doi.org/10.1109/IEEECONF35879.2020.9330359","url":null,"abstract":"A new array formation method for millimeter-wave (mm-wave) transverse slot scanning array antenna is proposed, which can effectively solve the grating lobes problem caused by the traditional array formation method. To verify the array formation method, a mm-wave scanning array antenna at 30GHz is designed, which consists of a traditional substrate integrated waveguide (SIW) 4 x 4 Butler Matrix (BM) feed network and 16 transverse slot elements. The distance between adjacent transverse slot elements is equal to half waveguide wavelength, and the transverse slot array antenna uses the metal cylinder matching method to improve the effective bandwidth of the array antenna, a −10dB impedance bandwidth (BW) of scanning array antenna from 28.9 to 31.04 GHz is simulated. The peak broadside gain of the array antenna is 13.7dB. This type of transverse slot scanning array antenna will have many applications in the future 5G mm-wave band.","PeriodicalId":135770,"journal":{"name":"2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131388558","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 : 2020-07-05DOI: 10.1109/IEEECONF35879.2020.9329548
D. Singh, K. R. Jha, S. Sharma
A compact flexible conformal antenna for multiband applications is proposed. The antenna is useful for the wide range of applications such as the IoT, Wi-Fi, Bluetooth, and ISM band. With a −6 dB impedance bandwidth, the antenna covers frequency bands from 0.773 −0.883 GHz, 2.1 – 2.7 GHz and 5.2 – 6.4 GHz. The antenna is designed on a flexible Acrylic sheet which makes it suitable for the conformal applications. The scheme to integrate the antenna to the IoT devices is also proposed. Additional results would be shown during the symposium.
{"title":"Low Cost Flexible Antenna for IoT Applications","authors":"D. Singh, K. R. Jha, S. Sharma","doi":"10.1109/IEEECONF35879.2020.9329548","DOIUrl":"https://doi.org/10.1109/IEEECONF35879.2020.9329548","url":null,"abstract":"A compact flexible conformal antenna for multiband applications is proposed. The antenna is useful for the wide range of applications such as the IoT, Wi-Fi, Bluetooth, and ISM band. With a −6 dB impedance bandwidth, the antenna covers frequency bands from 0.773 −0.883 GHz, 2.1 – 2.7 GHz and 5.2 – 6.4 GHz. The antenna is designed on a flexible Acrylic sheet which makes it suitable for the conformal applications. The scheme to integrate the antenna to the IoT devices is also proposed. Additional results would be shown during the symposium.","PeriodicalId":135770,"journal":{"name":"2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131465260","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 : 2020-07-05DOI: 10.1109/IEEECONF35879.2020.9329938
P. Nikitin, John Kim, K. Rao
In this paper, we explain how to design a UHF RFID tag antenna for ARC requirements, which are industry tag certification specifications. We focus on a $50 text{mm}times 30 text{mm}$ tag design that passes specs A through I. We explain how to model tag performance on complicated items that are part of ARC specs (such as jeans), and present modeling and simulation results which are in good agreement with measured data.
{"title":"RFID Tag Antenna Design for ARC Specs","authors":"P. Nikitin, John Kim, K. Rao","doi":"10.1109/IEEECONF35879.2020.9329938","DOIUrl":"https://doi.org/10.1109/IEEECONF35879.2020.9329938","url":null,"abstract":"In this paper, we explain how to design a UHF RFID tag antenna for ARC requirements, which are industry tag certification specifications. We focus on a $50 text{mm}times 30 text{mm}$ tag design that passes specs A through I. We explain how to model tag performance on complicated items that are part of ARC specs (such as jeans), and present modeling and simulation results which are in good agreement with measured data.","PeriodicalId":135770,"journal":{"name":"2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131981001","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 : 2020-07-05DOI: 10.1109/IEEECONF35879.2020.9329615
Junhui Peng, H. Cao, Decheng Wu, Zhiwei Sun, Jin Fan
In this paper, a novel approach of surface damage localization for the Five hundred meters Aperture Spherical radio Telescope (FAST) based on the focal-field distribution (FFD) is proposed. Firstly, according to the structure of the FAST, we model the FAST with surface damage caused by down-tied cables fatigue fractures. Then the FFD with different damage locations obtained by simulation are collected to form a full FFD feature database. Finally, the received signals of the FAST array feeds with surface damage is matched with the database to obtain the damage location. Simulation results show that the matching algorithm can effectively estimate the damage location.
{"title":"A Novel Method of Surface Damage Localization for FAST Active-reflector","authors":"Junhui Peng, H. Cao, Decheng Wu, Zhiwei Sun, Jin Fan","doi":"10.1109/IEEECONF35879.2020.9329615","DOIUrl":"https://doi.org/10.1109/IEEECONF35879.2020.9329615","url":null,"abstract":"In this paper, a novel approach of surface damage localization for the Five hundred meters Aperture Spherical radio Telescope (FAST) based on the focal-field distribution (FFD) is proposed. Firstly, according to the structure of the FAST, we model the FAST with surface damage caused by down-tied cables fatigue fractures. Then the FFD with different damage locations obtained by simulation are collected to form a full FFD feature database. Finally, the received signals of the FAST array feeds with surface damage is matched with the database to obtain the damage location. Simulation results show that the matching algorithm can effectively estimate the damage location.","PeriodicalId":135770,"journal":{"name":"2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132214881","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 : 2020-07-05DOI: 10.1109/IEEECONF35879.2020.9330380
Ge Zhao, Jing Rui Wang, Xu Shi, M. Tong
Ahstract-A dualband rectangular dielectric resonator antenna (DRA) with a circular patch over a metasurface for achieving circularly polarized radiation is proposed. The proposed antenna is comprised of a substrate with ground plane, a rectangular dielectric resonator (DR), a metasurface, a circle patch, and a coaxial probe. The metasurface upon the substrate can realize the circular polarization. The circle patch upon the rectangular DR can increase the reflection coefficient and realize the dual-band working mode. Simulation results show that the proposed DRA has a dual band of operating frequency which is 24.7% (4.23 GHz - 5.42 GHz) and 8.5% (5.60 GHz - 6.10 GHz), respectively. Also, the antenna has a circular polarization in the frequency range 5.60 GHz - 6.10 GHz and it could be widely used for 5G wireless communication. The antenna proposed in this paper has achieved dualband and circular polarization of dielectric resonator antenna simultaneously.
{"title":"A Dualband Dielectric Resonator Antenna over a Metasurface with Circular Polarization","authors":"Ge Zhao, Jing Rui Wang, Xu Shi, M. Tong","doi":"10.1109/IEEECONF35879.2020.9330380","DOIUrl":"https://doi.org/10.1109/IEEECONF35879.2020.9330380","url":null,"abstract":"Ahstract-A dualband rectangular dielectric resonator antenna (DRA) with a circular patch over a metasurface for achieving circularly polarized radiation is proposed. The proposed antenna is comprised of a substrate with ground plane, a rectangular dielectric resonator (DR), a metasurface, a circle patch, and a coaxial probe. The metasurface upon the substrate can realize the circular polarization. The circle patch upon the rectangular DR can increase the reflection coefficient and realize the dual-band working mode. Simulation results show that the proposed DRA has a dual band of operating frequency which is 24.7% (4.23 GHz - 5.42 GHz) and 8.5% (5.60 GHz - 6.10 GHz), respectively. Also, the antenna has a circular polarization in the frequency range 5.60 GHz - 6.10 GHz and it could be widely used for 5G wireless communication. The antenna proposed in this paper has achieved dualband and circular polarization of dielectric resonator antenna simultaneously.","PeriodicalId":135770,"journal":{"name":"2020 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132229157","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：