Pub Date : 2018-03-05DOI: 10.1109/IWAT.2018.8379173
Yiting Liu, Y. Jiao, Z. Weng, C. Zhang, Huan Zhang
A circularly polarized dielectric resonator antenna (DRA) millimeter wave array (MMW) with cavity-backed substrate integrated waveguide (SIW) feeding is proposed. This antenna is excited by a coaxial probe. The implemented antenna exhibits a simulated gain of almost 16 dBi and good radiation efficiency of around 96% are also obtained. The best axial ratio is almost less than 0.5 dB. It shows a good performance in radiation pattern.
{"title":"A high-gain dielectric resonator antenna array fed by back-cavity","authors":"Yiting Liu, Y. Jiao, Z. Weng, C. Zhang, Huan Zhang","doi":"10.1109/IWAT.2018.8379173","DOIUrl":"https://doi.org/10.1109/IWAT.2018.8379173","url":null,"abstract":"A circularly polarized dielectric resonator antenna (DRA) millimeter wave array (MMW) with cavity-backed substrate integrated waveguide (SIW) feeding is proposed. This antenna is excited by a coaxial probe. The implemented antenna exhibits a simulated gain of almost 16 dBi and good radiation efficiency of around 96% are also obtained. The best axial ratio is almost less than 0.5 dB. It shows a good performance in radiation pattern.","PeriodicalId":212550,"journal":{"name":"2018 International Workshop on Antenna Technology (iWAT)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126551496","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 : 2018-03-05DOI: 10.1109/IWAT.2018.8379239
J. Yamamoto, T. Nishimura, T. Ohgane, Y. Ogawa, D. Takeda, Y. Kishiyama
The massive MIMO technology which generates many sharp beams is known as a promising technology to accommodate rapidly-increasing traffic in mobile radio. In massive MIMO systems, there have already been a number of papers on 2-step beamforming where precoding matrix is calculated in a limited beam space after beam selection. In such a case, it is very important to select proper beams. Then, the beam shape affects the system performance. In the paper, we evaluate the achievable throughput performance for different beam-shaping schemes: a discrete Fourier transform (DFT) beam and Chebyshev weighted beams. The simulation results show that the DFT beam is a good choice although the optimum beam depends on the channel situation.
{"title":"Performance evaluation on beam shapes of a large MIMO system","authors":"J. Yamamoto, T. Nishimura, T. Ohgane, Y. Ogawa, D. Takeda, Y. Kishiyama","doi":"10.1109/IWAT.2018.8379239","DOIUrl":"https://doi.org/10.1109/IWAT.2018.8379239","url":null,"abstract":"The massive MIMO technology which generates many sharp beams is known as a promising technology to accommodate rapidly-increasing traffic in mobile radio. In massive MIMO systems, there have already been a number of papers on 2-step beamforming where precoding matrix is calculated in a limited beam space after beam selection. In such a case, it is very important to select proper beams. Then, the beam shape affects the system performance. In the paper, we evaluate the achievable throughput performance for different beam-shaping schemes: a discrete Fourier transform (DFT) beam and Chebyshev weighted beams. The simulation results show that the DFT beam is a good choice although the optimum beam depends on the channel situation.","PeriodicalId":212550,"journal":{"name":"2018 International Workshop on Antenna Technology (iWAT)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134552318","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 : 2018-03-05DOI: 10.1109/IWAT.2018.8379198
M. Arsalan, Falin Wu
A novel implementation of a Pseudomorphic High Electron Mobility Transistor (pHEMT) Low Noise Amplifier (LNA) for use in satellite communications tracking receiver is presented in this paper. The proposed design is of a single stage LNA working between frequency range of 2000 MHz to 2200 MHz. The designed LNA exhibit a Noise Figure (NF) of 0.320 dB which is less than the available pHEMT S Band LNA designs along with a transducer gain greater than 10dB. The Voltage Standing Wave Ratio (VSWR) of the designed and simulated LNA is 1:1.324. Simulation and measurements are taken in Advanced System Design (ADS) software. The circuit is designed and simulated using FR4 PCB laminate.
{"title":"An S band tracking receiver LNA for satellite communications","authors":"M. Arsalan, Falin Wu","doi":"10.1109/IWAT.2018.8379198","DOIUrl":"https://doi.org/10.1109/IWAT.2018.8379198","url":null,"abstract":"A novel implementation of a Pseudomorphic High Electron Mobility Transistor (pHEMT) Low Noise Amplifier (LNA) for use in satellite communications tracking receiver is presented in this paper. The proposed design is of a single stage LNA working between frequency range of 2000 MHz to 2200 MHz. The designed LNA exhibit a Noise Figure (NF) of 0.320 dB which is less than the available pHEMT S Band LNA designs along with a transducer gain greater than 10dB. The Voltage Standing Wave Ratio (VSWR) of the designed and simulated LNA is 1:1.324. Simulation and measurements are taken in Advanced System Design (ADS) software. The circuit is designed and simulated using FR4 PCB laminate.","PeriodicalId":212550,"journal":{"name":"2018 International Workshop on Antenna Technology (iWAT)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127423487","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 : 2018-03-05DOI: 10.1109/IWAT.2018.8379238
Lin Li, Xue-xia Yang, Ge-Liang Zhu, Hua-Wei Zhou
This paper proposes a compact high efficiency rectifying circuit with Class-F filter. The shunted diode topology structure is used to design the rectifying circuit with two-stage impedance match network. In order to reduce the power consumption on the diode, a Class-F filter consisting of two shunted microstrip lines has been added at the end of the diode. A cross-shaped microstrip stub works as DC-pass filter to reflect high harmonics and output stable DC voltage. The Class-F filter not only improves the conversion efficiency, but also makes the circuit structure more compact. According to the simulation results, the proposed circuit has a maximum conversion efficiency of 78% on 340Ω load at 11.2GHz when the input power is 19.5dBm. The RF-DC efficiencies are above 70% within 1.44GHz bandwidth from 10.4GHz to 11.84GHz. It is easy to be integrated with the receiving antenna and applied in the microwave power transmission system.
{"title":"A compact high-efficiency rectifying circuit with class-F filter","authors":"Lin Li, Xue-xia Yang, Ge-Liang Zhu, Hua-Wei Zhou","doi":"10.1109/IWAT.2018.8379238","DOIUrl":"https://doi.org/10.1109/IWAT.2018.8379238","url":null,"abstract":"This paper proposes a compact high efficiency rectifying circuit with Class-F filter. The shunted diode topology structure is used to design the rectifying circuit with two-stage impedance match network. In order to reduce the power consumption on the diode, a Class-F filter consisting of two shunted microstrip lines has been added at the end of the diode. A cross-shaped microstrip stub works as DC-pass filter to reflect high harmonics and output stable DC voltage. The Class-F filter not only improves the conversion efficiency, but also makes the circuit structure more compact. According to the simulation results, the proposed circuit has a maximum conversion efficiency of 78% on 340Ω load at 11.2GHz when the input power is 19.5dBm. The RF-DC efficiencies are above 70% within 1.44GHz bandwidth from 10.4GHz to 11.84GHz. It is easy to be integrated with the receiving antenna and applied in the microwave power transmission system.","PeriodicalId":212550,"journal":{"name":"2018 International Workshop on Antenna Technology (iWAT)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121800267","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 : 2018-03-05DOI: 10.1109/IWAT.2018.8379136
J. Schafer, D. Müller, T. Zwick, G. Eren, I. Kallfass
In this paper, we present the concept and experimental verification of a 240 GHz monolithic integrated frequency modulated continuous wave (FMCW) radar transmitter connected to a planar off-chip frequency scanning antenna. Different wire bond connection options are presented and compared. Simulation and measurement results for the interconnects as well as the overall system are presented. The system works at a center frequency of 240 GHz with a bandwidth of 20 GHz and has a scan range of 8o and a 3 dB-beamwidth of 4o.
{"title":"Tx front end concept for FMCW radar with frequency scanning antenna at 240 GHz","authors":"J. Schafer, D. Müller, T. Zwick, G. Eren, I. Kallfass","doi":"10.1109/IWAT.2018.8379136","DOIUrl":"https://doi.org/10.1109/IWAT.2018.8379136","url":null,"abstract":"In this paper, we present the concept and experimental verification of a 240 GHz monolithic integrated frequency modulated continuous wave (FMCW) radar transmitter connected to a planar off-chip frequency scanning antenna. Different wire bond connection options are presented and compared. Simulation and measurement results for the interconnects as well as the overall system are presented. The system works at a center frequency of 240 GHz with a bandwidth of 20 GHz and has a scan range of 8o and a 3 dB-beamwidth of 4o.","PeriodicalId":212550,"journal":{"name":"2018 International Workshop on Antenna Technology (iWAT)","volume":"300 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122981245","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 : 2018-03-01DOI: 10.1109/IWAT.2018.8379144
Shuncheng Tian, Hao Xue, Long Li
A broadband two-layer transparent metamaterial unit is proposed as a absorber at X-band, Ku-band and K-band. The transparent soda-lime glass and indium tin oxide (ITO) film were used to design the transparent metamaterial absorber unit. In the case of both TE-polarization and TM-polarization, a high absorption, more than 90%, is shown in the frequency range of 8.1GHz to 28.7GHz. The thickness of the metamaterial absorber unit is 3.3mm. The metamaterial absorber unit has wide incident angle stability and high transparency. It can be widely used in all kinds of household appliances in order to reduce the electromagnetic radiation because the structure is transparent in the visible light band.
{"title":"An broadband transparent metamaterial absorber using an ITO resistive-film","authors":"Shuncheng Tian, Hao Xue, Long Li","doi":"10.1109/IWAT.2018.8379144","DOIUrl":"https://doi.org/10.1109/IWAT.2018.8379144","url":null,"abstract":"A broadband two-layer transparent metamaterial unit is proposed as a absorber at X-band, Ku-band and K-band. The transparent soda-lime glass and indium tin oxide (ITO) film were used to design the transparent metamaterial absorber unit. In the case of both TE-polarization and TM-polarization, a high absorption, more than 90%, is shown in the frequency range of 8.1GHz to 28.7GHz. The thickness of the metamaterial absorber unit is 3.3mm. The metamaterial absorber unit has wide incident angle stability and high transparency. It can be widely used in all kinds of household appliances in order to reduce the electromagnetic radiation because the structure is transparent in the visible light band.","PeriodicalId":212550,"journal":{"name":"2018 International Workshop on Antenna Technology (iWAT)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125163453","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 : 2018-03-01DOI: 10.1109/IWAT.2018.8379181
Zhentao Zhao, Q. Zeng
This paper presents the design and analysis of a dual-band planar inverted-F antenna (PIFA) with three resonance modes to satisfy the requirement for both TVWS and 2.4-GHz ISM applications. The third resonance mode is achieved by straightforwardly cutting a U-shaped slot on the inner patch of the PIFA around the feeding point while no parasitic element is required, thus the proposed antenna can be easily fabricated by folding a single copper sheet. Furthermore, the frequency of each resonance mode can be flexibly adjusted by tuning different dimension parameters so as to control the frequency and bandwidth (BW) of the two operating bands. The measured fractional BW of the two frequency bands are 54% (460–800 MHz) and 11.3% (2.34–2.62 GHz), respectively.
{"title":"Design and analysis of a dual-band folded PIFA for TVWS and 2.4-GHz ISM applications","authors":"Zhentao Zhao, Q. Zeng","doi":"10.1109/IWAT.2018.8379181","DOIUrl":"https://doi.org/10.1109/IWAT.2018.8379181","url":null,"abstract":"This paper presents the design and analysis of a dual-band planar inverted-F antenna (PIFA) with three resonance modes to satisfy the requirement for both TVWS and 2.4-GHz ISM applications. The third resonance mode is achieved by straightforwardly cutting a U-shaped slot on the inner patch of the PIFA around the feeding point while no parasitic element is required, thus the proposed antenna can be easily fabricated by folding a single copper sheet. Furthermore, the frequency of each resonance mode can be flexibly adjusted by tuning different dimension parameters so as to control the frequency and bandwidth (BW) of the two operating bands. The measured fractional BW of the two frequency bands are 54% (460–800 MHz) and 11.3% (2.34–2.62 GHz), respectively.","PeriodicalId":212550,"journal":{"name":"2018 International Workshop on Antenna Technology (iWAT)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125376532","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 : 2018-03-01DOI: 10.1109/IWAT.2018.8379130
Jun Li, Yejun He
In this paper, a novel planar inverted-F antenna (PIFA) operating at six bands (GSM850, GSM900, DCS1800, PCS1900, UMTS2100, LTE2300) is proposed. By adding a parasitic element and two slots in the patch of basic PIFA, the bandwidth on the upper frequency band can be improved to cover more communication systems. All the simulated and measured results show that the proposed PIFA possesses −6dB bandwidth 185 MHz (805 MHz to 990 MHz) at the lower frequency band and 815 MHz (1705 MHz to 2520 MHz) at the upper frequency band. Moreover, the proposed antenna exhibits good performance of total radiated power (TRP), (18 ∼28 dBm) and total isotropic sensitivity (TIS), (−91 ∼−107 dBm), under the free space environment. Thus, the novel PIFA is suitable for 2G/3G/LTE mobile communication systems.
{"title":"A novel planar inverted-F antenna for 2G/3G/LTE systems","authors":"Jun Li, Yejun He","doi":"10.1109/IWAT.2018.8379130","DOIUrl":"https://doi.org/10.1109/IWAT.2018.8379130","url":null,"abstract":"In this paper, a novel planar inverted-F antenna (PIFA) operating at six bands (GSM850, GSM900, DCS1800, PCS1900, UMTS2100, LTE2300) is proposed. By adding a parasitic element and two slots in the patch of basic PIFA, the bandwidth on the upper frequency band can be improved to cover more communication systems. All the simulated and measured results show that the proposed PIFA possesses −6dB bandwidth 185 MHz (805 MHz to 990 MHz) at the lower frequency band and 815 MHz (1705 MHz to 2520 MHz) at the upper frequency band. Moreover, the proposed antenna exhibits good performance of total radiated power (TRP), (18 ∼28 dBm) and total isotropic sensitivity (TIS), (−91 ∼−107 dBm), under the free space environment. Thus, the novel PIFA is suitable for 2G/3G/LTE mobile communication systems.","PeriodicalId":212550,"journal":{"name":"2018 International Workshop on Antenna Technology (iWAT)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126852853","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 : 2018-03-01DOI: 10.1109/IWAT.2018.8379179
Qian Meng, Wanchen Yang, W. Che, Siou-Li Chen, Chenyu Zhou
A novel low-profile dual-circularly polarized metasurface antenna with wideband and widebeam circular polarization (CP) radiations is proposed. It is constructed by an array of polarization-rotation metasurface (PRMS) cells and fed by a new cross aperture with four narrow slots in the ground plane. Due to the polarization-rotation property of the PRMS structure, a pair of linear-polarization (LP) aperture-coupling feedings can respectively inspire left-hand and right-hand CP (LHCP, RHCP) radiations. Furthermore, the proposed antenna has a compact structure with a low profile of 0.07λ0 at 5 GHz. Simulated results show that the 10-dB impedance bandwidths for LHCP and RHCP states are respectively 36.0% (3.78–5.58 GHz) and 24.6% (4.26–5.44 GHz). The 3-dB axial ratio (AR) bandwidth for the LHCP state is 17.4% (4.19–5.42 GHz) with large 3-dB AR beamwidths of 103.22° and 55.65° in the xoz and yoz planes, while for the RHCP state, the AR bandwidth is 17.0% (4.50–5.35 GHz) with large beamwidths of 77.93° and 99.67° at the two planes. In addition, the polarization isolation within the two AR bands is over 15 dB.
{"title":"Novel wideband low-profile dual-circularly polarized metasurface antenna","authors":"Qian Meng, Wanchen Yang, W. Che, Siou-Li Chen, Chenyu Zhou","doi":"10.1109/IWAT.2018.8379179","DOIUrl":"https://doi.org/10.1109/IWAT.2018.8379179","url":null,"abstract":"A novel low-profile dual-circularly polarized metasurface antenna with wideband and widebeam circular polarization (CP) radiations is proposed. It is constructed by an array of polarization-rotation metasurface (PRMS) cells and fed by a new cross aperture with four narrow slots in the ground plane. Due to the polarization-rotation property of the PRMS structure, a pair of linear-polarization (LP) aperture-coupling feedings can respectively inspire left-hand and right-hand CP (LHCP, RHCP) radiations. Furthermore, the proposed antenna has a compact structure with a low profile of 0.07λ0 at 5 GHz. Simulated results show that the 10-dB impedance bandwidths for LHCP and RHCP states are respectively 36.0% (3.78–5.58 GHz) and 24.6% (4.26–5.44 GHz). The 3-dB axial ratio (AR) bandwidth for the LHCP state is 17.4% (4.19–5.42 GHz) with large 3-dB AR beamwidths of 103.22° and 55.65° in the xoz and yoz planes, while for the RHCP state, the AR bandwidth is 17.0% (4.50–5.35 GHz) with large beamwidths of 77.93° and 99.67° at the two planes. In addition, the polarization isolation within the two AR bands is over 15 dB.","PeriodicalId":212550,"journal":{"name":"2018 International Workshop on Antenna Technology (iWAT)","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115087264","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 : 2018-03-01DOI: 10.1109/IWAT.2018.8379230
Yan Zhang, Jinhao Wang, T. Dong, Jie Yin
In this paper, a new type of frequency and polarization reconfigurable FSS (Frequency selective surface) is designed. By using liquid crystal material, the frequency of the FSS can be reconfigured. The dipole sub-module is used. The upper and lower dipoles separated by the dielectric substrate are orthogonal to each other. The adjacent short-term dipole passes PIN diodes connected, and the switch of the dipoles controls the polarization selection of FSS in the passband. The experimental results show that the FSS can select the TE and TM waves, and the polarization selection and reconfiguration characteristics are obvious.
{"title":"A frequency and polarization reconfigurable frequency selective surface based on liquid crystal","authors":"Yan Zhang, Jinhao Wang, T. Dong, Jie Yin","doi":"10.1109/IWAT.2018.8379230","DOIUrl":"https://doi.org/10.1109/IWAT.2018.8379230","url":null,"abstract":"In this paper, a new type of frequency and polarization reconfigurable FSS (Frequency selective surface) is designed. By using liquid crystal material, the frequency of the FSS can be reconfigured. The dipole sub-module is used. The upper and lower dipoles separated by the dielectric substrate are orthogonal to each other. The adjacent short-term dipole passes PIN diodes connected, and the switch of the dipoles controls the polarization selection of FSS in the passband. The experimental results show that the FSS can select the TE and TM waves, and the polarization selection and reconfiguration characteristics are obvious.","PeriodicalId":212550,"journal":{"name":"2018 International Workshop on Antenna Technology (iWAT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129572501","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}
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