Pub Date : 2018-06-01DOI: 10.1109/MWSYM.2018.8439200
I. Sezgin, T. Eriksson, J. Gustavsson, C. Fager
Sigma-delta-over-fiber (SDoF) using high speed-low cost optical components for datacom enables high speed transmission at X-band. This paper examines the limitations of SDoF in terms of maximum frequencies and highest bit rates. Different modulation formats, symbol rates and carrier frequencies are investigated. A high speed 850 nm vertical-cavity surface-emiting-laser (VCSEL) is used as an optical source to transmit the optical signal over a 50 meter, OM4, multimode fiber (MMF). Error vector magnitude (EVM) less than 6% is achieved at a 12-GHz center frequency for a 8-Gbps QAM256 modulated signal.
{"title":"A Flexible Multi-Gbps Transmitter Using Ultra-High Speed Sigma- Delta-over- Fiber","authors":"I. Sezgin, T. Eriksson, J. Gustavsson, C. Fager","doi":"10.1109/MWSYM.2018.8439200","DOIUrl":"https://doi.org/10.1109/MWSYM.2018.8439200","url":null,"abstract":"Sigma-delta-over-fiber (SDoF) using high speed-low cost optical components for datacom enables high speed transmission at X-band. This paper examines the limitations of SDoF in terms of maximum frequencies and highest bit rates. Different modulation formats, symbol rates and carrier frequencies are investigated. A high speed 850 nm vertical-cavity surface-emiting-laser (VCSEL) is used as an optical source to transmit the optical signal over a 50 meter, OM4, multimode fiber (MMF). Error vector magnitude (EVM) less than 6% is achieved at a 12-GHz center frequency for a 8-Gbps QAM256 modulated signal.","PeriodicalId":6675,"journal":{"name":"2018 IEEE/MTT-S International Microwave Symposium - IMS","volume":"366 1","pages":"1195-1198"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76524731","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 : 2018-06-01DOI: 10.1109/MWSYM.2018.8439629
Ningning Yan, Kaixue Ma, Yun He, Ze Jian
A novel 24-GHz cavity backed slot antenna with out-of-phase power divider based on multilayer air-filled print circuit board (PCB) for automotive radar is presented. By etching the bow-tie slot and rectangular slot on the antenna element, the two resonant frequencies at 23.45GHz and 24.15GHz are stimulated. For the antenna element, the measured operating frequency band is 23–25.01GHz and the maximum measured gain is 7.0SdBi. And then, the antenna array with 16 antenna elements is proposed. The microstrip-to-slotline power divider with 180°phase difference is designed to compose the feeding network. According to the measured results of the antenna array, the impedance bandwidth is from 23.22-25.03GHz and the maximum gain is 14.83dBi. In addition, the front-back ratio (F/B) is larger than 25dB.
{"title":"A Novel 24-GHz Air-filled Cavity-backed Slot Antenna Array with Out-of-phase Power Divider for Automotive Radar System","authors":"Ningning Yan, Kaixue Ma, Yun He, Ze Jian","doi":"10.1109/MWSYM.2018.8439629","DOIUrl":"https://doi.org/10.1109/MWSYM.2018.8439629","url":null,"abstract":"A novel 24-GHz cavity backed slot antenna with out-of-phase power divider based on multilayer air-filled print circuit board (PCB) for automotive radar is presented. By etching the bow-tie slot and rectangular slot on the antenna element, the two resonant frequencies at 23.45GHz and 24.15GHz are stimulated. For the antenna element, the measured operating frequency band is 23–25.01GHz and the maximum measured gain is 7.0SdBi. And then, the antenna array with 16 antenna elements is proposed. The microstrip-to-slotline power divider with 180°phase difference is designed to compose the feeding network. According to the measured results of the antenna array, the impedance bandwidth is from 23.22-25.03GHz and the maximum gain is 14.83dBi. In addition, the front-back ratio (F/B) is larger than 25dB.","PeriodicalId":6675,"journal":{"name":"2018 IEEE/MTT-S International Microwave Symposium - IMS","volume":"55 1","pages":"1589-1592"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76651951","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 : 2018-06-01DOI: 10.1109/MWSYM.2018.8439847
W. Tsai, I. Ocket, Joren Vaes, M. Cauwe, Patrick Revnacrt, B. Nauwelaers
This paper demonstrates a D-band transition between a coplanar waveguide line and a rectangular dielectric waveguide> The transition uses an intermediate metallic waveguide partially implemented on printed circuit board (PCB) to enhance the coupling efficiency and to offer a solid assembly base. The transition was designed to convert the CPW mode to the $pmb{E_{11}^{y}}$ mode in a dielectric rectangular waveguide. In this paper we present the design, fabrication and measurement data, showing a 7 dB measured insertion loss for a back-to-back transition connected by a 80 mm long section of polystyrene, measured with GSG on-wafer probes.
{"title":"Novel Broadband Transition for Rectangular Dielectric Waveguide to Planar Circuit Board at D Band","authors":"W. Tsai, I. Ocket, Joren Vaes, M. Cauwe, Patrick Revnacrt, B. Nauwelaers","doi":"10.1109/MWSYM.2018.8439847","DOIUrl":"https://doi.org/10.1109/MWSYM.2018.8439847","url":null,"abstract":"This paper demonstrates a D-band transition between a coplanar waveguide line and a rectangular dielectric waveguide> The transition uses an intermediate metallic waveguide partially implemented on printed circuit board (PCB) to enhance the coupling efficiency and to offer a solid assembly base. The transition was designed to convert the CPW mode to the $pmb{E_{11}^{y}}$ mode in a dielectric rectangular waveguide. In this paper we present the design, fabrication and measurement data, showing a 7 dB measured insertion loss for a back-to-back transition connected by a 80 mm long section of polystyrene, measured with GSG on-wafer probes.","PeriodicalId":6675,"journal":{"name":"2018 IEEE/MTT-S International Microwave Symposium - IMS","volume":"50 1","pages":"386-389"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76682380","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 : 2018-06-01DOI: 10.1109/MWSYM.2018.8439592
T. Canning, Bjoern Herrmann, Haedong Jang, Z. Mokhti, Richard Wilson
This work introduces a new method for selecting the optimal Doherty power amplifier (PA) asymmetry ratio considering both the Doherty topology limitations, and the limitations of the transistor technology. The method is scalable with Doherty complexity and is technology agnostic. An example Doherty is also briefly shown which supports this new method, with excellent alignment shown between measured and predicted performance.
{"title":"A Novel Approach to Selecting Doherty Amplifier Asymmetry","authors":"T. Canning, Bjoern Herrmann, Haedong Jang, Z. Mokhti, Richard Wilson","doi":"10.1109/MWSYM.2018.8439592","DOIUrl":"https://doi.org/10.1109/MWSYM.2018.8439592","url":null,"abstract":"This work introduces a new method for selecting the optimal Doherty power amplifier (PA) asymmetry ratio considering both the Doherty topology limitations, and the limitations of the transistor technology. The method is scalable with Doherty complexity and is technology agnostic. An example Doherty is also briefly shown which supports this new method, with excellent alignment shown between measured and predicted performance.","PeriodicalId":6675,"journal":{"name":"2018 IEEE/MTT-S International Microwave Symposium - IMS","volume":"355 1","pages":"469-472"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76494267","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 : 2018-06-01DOI: 10.1109/MWSYM.2018.8439391
L. John, M. Ohlrogge, S. Wagner, C. Friesicke, A. Tessmann, A. Leuther, T. Zwick
An in situ load-pull MMIC with preamplifier and tunable output matching network in a 35 nm InAlAs/InGaAs technology is presented in this paper. The load impedance tuning is realized using an open-circuit stub network with shunt-FETs. The tunable load impedance range and the large-signal characterization of a 2×15 μm device is demonstrated at 300 GHz. With this MMIC the unique characterization and large-signal model validation of mHEMT devices at sub-mm wave frequencies is possible. The total chip area required for large-signal characterization of a single device is 1850 μm × 400 μm.
{"title":"In situ Load- Pull MMIC for Large-Signal Characterization of mHEMT Devices at Submillimeter- Wave Frequencies","authors":"L. John, M. Ohlrogge, S. Wagner, C. Friesicke, A. Tessmann, A. Leuther, T. Zwick","doi":"10.1109/MWSYM.2018.8439391","DOIUrl":"https://doi.org/10.1109/MWSYM.2018.8439391","url":null,"abstract":"An in situ load-pull MMIC with preamplifier and tunable output matching network in a 35 nm InAlAs/InGaAs technology is presented in this paper. The load impedance tuning is realized using an open-circuit stub network with shunt-FETs. The tunable load impedance range and the large-signal characterization of a 2×15 μm device is demonstrated at 300 GHz. With this MMIC the unique characterization and large-signal model validation of mHEMT devices at sub-mm wave frequencies is possible. The total chip area required for large-signal characterization of a single device is 1850 μm × 400 μm.","PeriodicalId":6675,"journal":{"name":"2018 IEEE/MTT-S International Microwave Symposium - IMS","volume":"18 1","pages":"761-764"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76843593","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 : 2018-06-01DOI: 10.1109/MWSYM.2018.8439517
J. Dunworth, B. Ku, Yu-Chin Ou, D. Lu, P. Mouat, A. Homayoun, K. Chakraborty, Andrew Arnett, Gang Liu, T. Segoria, J. Lerdworatawee, Joung Won Park, Hyun-Chul Park, H. Hedayati, A. Tassoudji, Keith Douglas, V. Aparin
A 28GHz phased array transceiver with RF/IF conversion in 28nm bulk CMOS supports up to 12 antenna elements each on 2 MIMO layers. The transceiver is targeted for small antenna arrays in mobile user equipment, implements an AMPM compensated PA, passive 3b phase shifters and supports tiling to extend the antenna array size for prototype basestation applications. Radiated results are presented for both UE and basestation size arrays.
{"title":"28GHz Phased Array Transceiver in 28nm Bulk CMOS for 5G Prototype User Equipment and Base Stations","authors":"J. Dunworth, B. Ku, Yu-Chin Ou, D. Lu, P. Mouat, A. Homayoun, K. Chakraborty, Andrew Arnett, Gang Liu, T. Segoria, J. Lerdworatawee, Joung Won Park, Hyun-Chul Park, H. Hedayati, A. Tassoudji, Keith Douglas, V. Aparin","doi":"10.1109/MWSYM.2018.8439517","DOIUrl":"https://doi.org/10.1109/MWSYM.2018.8439517","url":null,"abstract":"A 28GHz phased array transceiver with RF/IF conversion in 28nm bulk CMOS supports up to 12 antenna elements each on 2 MIMO layers. The transceiver is targeted for small antenna arrays in mobile user equipment, implements an AMPM compensated PA, passive 3b phase shifters and supports tiling to extend the antenna array size for prototype basestation applications. Radiated results are presented for both UE and basestation size arrays.","PeriodicalId":6675,"journal":{"name":"2018 IEEE/MTT-S International Microwave Symposium - IMS","volume":"71 1","pages":"1330-1333"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75725302","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 : 2018-06-01DOI: 10.1109/MWSYM.2018.8439133
R. Reese, M. Jost, E. Polat, M. Nickel, R. Jakoby, H. Maune
This work presents a compact and lightweight dielectric waveguide (DW) switch at W-band, which uses liquid crystal (LC) technology for tuning multimode interference (MMI). The device, designed for 85 to 105 GHz, is based on the interference pattern also known as self-imaging, which occurs due to a higher order mode propagation in a multimode waveguide. If the multimode waveguide is asymmetrically excited, a phase shift difference arises between two occurring field maxima. By placing LC in the region of one field maximum the phase shift can be adjusted by means of the tunable permittivity. This allows to control the interference pattern and therefore the position of the field maximum at the output of the multimode waveguide, where single mode DWs are connected. In the measurements, a port isolation of 40 dB at 94 GHz was achieved, while the other switching configuration shows a port isolation of 10 dB at 110 GHz. For both cases, the input reflection is below −15 dB over the whole frequency range.
{"title":"A Dielectric Waveguide Switch based on Tunable Multimode Interference at W-band","authors":"R. Reese, M. Jost, E. Polat, M. Nickel, R. Jakoby, H. Maune","doi":"10.1109/MWSYM.2018.8439133","DOIUrl":"https://doi.org/10.1109/MWSYM.2018.8439133","url":null,"abstract":"This work presents a compact and lightweight dielectric waveguide (DW) switch at W-band, which uses liquid crystal (LC) technology for tuning multimode interference (MMI). The device, designed for 85 to 105 GHz, is based on the interference pattern also known as self-imaging, which occurs due to a higher order mode propagation in a multimode waveguide. If the multimode waveguide is asymmetrically excited, a phase shift difference arises between two occurring field maxima. By placing LC in the region of one field maximum the phase shift can be adjusted by means of the tunable permittivity. This allows to control the interference pattern and therefore the position of the field maximum at the output of the multimode waveguide, where single mode DWs are connected. In the measurements, a port isolation of 40 dB at 94 GHz was achieved, while the other switching configuration shows a port isolation of 10 dB at 110 GHz. For both cases, the input reflection is below −15 dB over the whole frequency range.","PeriodicalId":6675,"journal":{"name":"2018 IEEE/MTT-S International Microwave Symposium - IMS","volume":"22 1","pages":"179-182"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80095484","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 : 2018-06-01DOI: 10.1109/MWSYM.2018.8439603
Harikesh, A. Basu, M. Abegaonkar, S. Koul
In this paper, a simple direct demodulation Doppler radar is proposed to detect the respiration rate through the wall using Hilbert vibration decomposition (HVD) at 2.4 GHz. For through the wall detection of the human subject, the measurements are taken by varying the respiration rate, with different positions of human subject with respect to the radar and different background behind the human subject. This method is suitable for the detection of human subject in natural calamities or disasters. Using this method, through the wall respiration rate of human subject can be detected up to 2–3 meter.
{"title":"Through The Wall Respiration Rate Detection Using Hilbert Vibrational Decomposition","authors":"Harikesh, A. Basu, M. Abegaonkar, S. Koul","doi":"10.1109/MWSYM.2018.8439603","DOIUrl":"https://doi.org/10.1109/MWSYM.2018.8439603","url":null,"abstract":"In this paper, a simple direct demodulation Doppler radar is proposed to detect the respiration rate through the wall using Hilbert vibration decomposition (HVD) at 2.4 GHz. For through the wall detection of the human subject, the measurements are taken by varying the respiration rate, with different positions of human subject with respect to the radar and different background behind the human subject. This method is suitable for the detection of human subject in natural calamities or disasters. Using this method, through the wall respiration rate of human subject can be detected up to 2–3 meter.","PeriodicalId":6675,"journal":{"name":"2018 IEEE/MTT-S International Microwave Symposium - IMS","volume":"17 1","pages":"961-963"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81651407","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 : 2018-06-01DOI: 10.1109/MWSYM.2018.8439287
M. Bertrand, Em Pistone, G. Acri, D. Kaddour, F. Podevin, V. Puyal, S. Wipf, C. Wipf, M. Wietstruck, M. Kaynak, P. Ferrari
This paper presents D-band mm-wave SIWs, which are embedded in a high-resistivity silicon interposer. Thanks to the interposer thickness equal to $pmb{70 mu} mathbf{m}$, high-performance SIW were obtained, with measured attenuation constant between 0.4 and 0.6 dB/mm from 110 GHz to 170 GHz. These first results pave the way for the realization of high performance passive circuits and antennas embedded in the interposer. Also, by using a fully shielded waveguide highly insensitive to adj acent wave-guiding and radiating structures, this topology provides significant advantages for packaging solutions at mm-wave frequencies. Such a functionalized interposer could offer lower cost, higher electrical performance as compared to standard CMOS technologies.
{"title":"Substrate Integrated Waveguides for mm-wave Functionalized Silicon Interposer","authors":"M. Bertrand, Em Pistone, G. Acri, D. Kaddour, F. Podevin, V. Puyal, S. Wipf, C. Wipf, M. Wietstruck, M. Kaynak, P. Ferrari","doi":"10.1109/MWSYM.2018.8439287","DOIUrl":"https://doi.org/10.1109/MWSYM.2018.8439287","url":null,"abstract":"This paper presents D-band mm-wave SIWs, which are embedded in a high-resistivity silicon interposer. Thanks to the interposer thickness equal to $pmb{70 mu} mathbf{m}$, high-performance SIW were obtained, with measured attenuation constant between 0.4 and 0.6 dB/mm from 110 GHz to 170 GHz. These first results pave the way for the realization of high performance passive circuits and antennas embedded in the interposer. Also, by using a fully shielded waveguide highly insensitive to adj acent wave-guiding and radiating structures, this topology provides significant advantages for packaging solutions at mm-wave frequencies. Such a functionalized interposer could offer lower cost, higher electrical performance as compared to standard CMOS technologies.","PeriodicalId":6675,"journal":{"name":"2018 IEEE/MTT-S International Microwave Symposium - IMS","volume":"96 1","pages":"875-878"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82769484","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 : 2018-06-01DOI: 10.1109/MWSYM.2018.8439653
E. Naglich, Sanghoon Shin, Spencer O. Albright
Ahstract- The integration of a resonant power sensor, switch driver circuit, and switchable bandstop filter is shown in this paper. The co-design of these circuits enable a switchable bandstop filter that autonomously responds to an unexpected above-threshold interfering signal within its bandwidth in orders of magnitude less time than conventional switchable or tunable bandstop filters. In contrast to limiter circuits that are based on PIN diodes that are switched by RF power, the proposed autonomously-switchable bandstop filter has high linearity in all states. A third-order suspended-stripline prototype switchable bandstop filter with a second-order resonant power sensor was fabricated and measured to test the technique at 2.15 GHz. Within 14–22.2 ns of the arrival of an above-threshold interfering signal, the fabricated driver circuit switches a bandstop filter with 18 dB attenuation and an OIP3 value of over 38 dBm.
{"title":"Autonomously-Switchable Bandstop Filters with Integrated Sensor and Driver Circuitry","authors":"E. Naglich, Sanghoon Shin, Spencer O. Albright","doi":"10.1109/MWSYM.2018.8439653","DOIUrl":"https://doi.org/10.1109/MWSYM.2018.8439653","url":null,"abstract":"Ahstract- The integration of a resonant power sensor, switch driver circuit, and switchable bandstop filter is shown in this paper. The co-design of these circuits enable a switchable bandstop filter that autonomously responds to an unexpected above-threshold interfering signal within its bandwidth in orders of magnitude less time than conventional switchable or tunable bandstop filters. In contrast to limiter circuits that are based on PIN diodes that are switched by RF power, the proposed autonomously-switchable bandstop filter has high linearity in all states. A third-order suspended-stripline prototype switchable bandstop filter with a second-order resonant power sensor was fabricated and measured to test the technique at 2.15 GHz. Within 14–22.2 ns of the arrival of an above-threshold interfering signal, the fabricated driver circuit switches a bandstop filter with 18 dB attenuation and an OIP3 value of over 38 dBm.","PeriodicalId":6675,"journal":{"name":"2018 IEEE/MTT-S International Microwave Symposium - IMS","volume":"23 1","pages":"394-396"},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79655398","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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