Pub Date : 2006-09-01DOI: 10.1109/EMICC.2006.282687
M. Sarfraz, M. Akkul
This paper describes the design of a 30W GaAs pHEMT PA (power amplifier) for WiMAX applications. The PA is realized on a CuW carrier with various ceramic matching components. The PA attained 10dB small signal gain and 30W CW output power with a drain efficiency of around 60% at a supply voltage of 12V. Under WiMAX 802.16-2004 OFDM modulation (3.5MHz BW, 64QAM sub carrier modulation and peak to average ratio of 10dB) the PA achieves better than 2% EVM (error vector magnitude), -45dBc ACPR (adjacent channel power ratio) at 34dBm (2.5W) Pavg (average output power) with 16% average drain efficiency in a frequency band of 3.3-3.7GHz
{"title":"30-Watt Power Amplifier for 3.5GHz WiMAX Base station Application","authors":"M. Sarfraz, M. Akkul","doi":"10.1109/EMICC.2006.282687","DOIUrl":"https://doi.org/10.1109/EMICC.2006.282687","url":null,"abstract":"This paper describes the design of a 30W GaAs pHEMT PA (power amplifier) for WiMAX applications. The PA is realized on a CuW carrier with various ceramic matching components. The PA attained 10dB small signal gain and 30W CW output power with a drain efficiency of around 60% at a supply voltage of 12V. Under WiMAX 802.16-2004 OFDM modulation (3.5MHz BW, 64QAM sub carrier modulation and peak to average ratio of 10dB) the PA achieves better than 2% EVM (error vector magnitude), -45dBc ACPR (adjacent channel power ratio) at 34dBm (2.5W) Pavg (average output power) with 16% average drain efficiency in a frequency band of 3.3-3.7GHz","PeriodicalId":269652,"journal":{"name":"2006 European Microwave Integrated Circuits Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124204185","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 : 2006-09-01DOI: 10.1109/EMICC.2006.282744
J. Stake, T. Bryllert, T. Arezoo Emadi, M. Sadeghi, J. Vukusic
We report on the design and MBE-growth of heterostructure barrier varactor (HBV) diode materials. The quality and performance of in-house HBV materials are presented. The design methodology and electro-thermal simulations of high power HBV multipliers for signal generation in the frequency range 100 - 300 GHz are also presented. Finally, a state-of-the-art tripler efficiency of 21% and a quintupler efficiency of 11% for W-band multipliers have been demonstrated
{"title":"High Efficiency HBV Multipliers","authors":"J. Stake, T. Bryllert, T. Arezoo Emadi, M. Sadeghi, J. Vukusic","doi":"10.1109/EMICC.2006.282744","DOIUrl":"https://doi.org/10.1109/EMICC.2006.282744","url":null,"abstract":"We report on the design and MBE-growth of heterostructure barrier varactor (HBV) diode materials. The quality and performance of in-house HBV materials are presented. The design methodology and electro-thermal simulations of high power HBV multipliers for signal generation in the frequency range 100 - 300 GHz are also presented. Finally, a state-of-the-art tripler efficiency of 21% and a quintupler efficiency of 11% for W-band multipliers have been demonstrated","PeriodicalId":269652,"journal":{"name":"2006 European Microwave Integrated Circuits Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126564143","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 : 2006-09-01DOI: 10.1109/EMICC.2006.282675
S. Rumer, M. Thornber
Recent advances in the design of digital signal processing (DSP) equipments have broadened the appeal of this technology to satellite customers. Each digital signal processor has up and down converters associated with it in order to interface with the rest of a payload RF subsystem, consequently the need for multi-channel frequency converters that can provide a low cost per channel solution is now of increasing importance. The subject of this paper is the design of such a multi channel down-converter that provides an L band to Baseband frequency conversion, which has typically 100-200 channels. The key factor in achieving the desired low cost per channel is the use of a multi layer, multi RF channel, high temperature cofired ceramic tile. This complex tile incorporates RF tracks as well as DC interconnections and local oscillator signal distribution. The module design presented in this paper uses 13 hybrids per RF channel, thus having 104 hybrids for a fully populated 8 channel down-converter module. This has been designed and developed by EADS Astrium UK as part of the next generation processor (NGP) development jointly funded with ESA
{"title":"A Multi Channel Down-converter Module Exploiting Recent Advances in Multi layer RF Packaging Techniques","authors":"S. Rumer, M. Thornber","doi":"10.1109/EMICC.2006.282675","DOIUrl":"https://doi.org/10.1109/EMICC.2006.282675","url":null,"abstract":"Recent advances in the design of digital signal processing (DSP) equipments have broadened the appeal of this technology to satellite customers. Each digital signal processor has up and down converters associated with it in order to interface with the rest of a payload RF subsystem, consequently the need for multi-channel frequency converters that can provide a low cost per channel solution is now of increasing importance. The subject of this paper is the design of such a multi channel down-converter that provides an L band to Baseband frequency conversion, which has typically 100-200 channels. The key factor in achieving the desired low cost per channel is the use of a multi layer, multi RF channel, high temperature cofired ceramic tile. This complex tile incorporates RF tracks as well as DC interconnections and local oscillator signal distribution. The module design presented in this paper uses 13 hybrids per RF channel, thus having 104 hybrids for a fully populated 8 channel down-converter module. This has been designed and developed by EADS Astrium UK as part of the next generation processor (NGP) development jointly funded with ESA","PeriodicalId":269652,"journal":{"name":"2006 European Microwave Integrated Circuits Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128931536","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 : 2006-09-01DOI: 10.1109/EMICC.2006.282787
F. V. van Vliet, A. de Boer, G.C. Visser
This paper presents very recent achievements in the silicon implementation of phase and amplitude control for active electronically steered arrays. The IC combines 6-bit amplitude control with more than 20 dB amplitude range, including control logic and series-to-parallel converters. The IC is a step forward in lowering active array cost and presents a small IC area with a high phase accuracy and dynamic range
{"title":"S-Band Sige Phase and Amplitude Control MMIC","authors":"F. V. van Vliet, A. de Boer, G.C. Visser","doi":"10.1109/EMICC.2006.282787","DOIUrl":"https://doi.org/10.1109/EMICC.2006.282787","url":null,"abstract":"This paper presents very recent achievements in the silicon implementation of phase and amplitude control for active electronically steered arrays. The IC combines 6-bit amplitude control with more than 20 dB amplitude range, including control logic and series-to-parallel converters. The IC is a step forward in lowering active array cost and presents a small IC area with a high phase accuracy and dynamic range","PeriodicalId":269652,"journal":{"name":"2006 European Microwave Integrated Circuits Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131085611","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 : 2006-09-01DOI: 10.1109/EMICC.2006.282685
Guogong Wang, Hao-Chih Yuan, Z. Ma
The influence of interconnect parasitics on the lateral scaling of emitter stripe width of large-area SiGe power heterojunction bipolar transistors (HBTs) are analytically studied and experimentally verified. It is found that, due to the increased parasitics along with the increase of device area, the maximum oscillation frequency (fmax ) of a power SiGe HBT cannot be improved monotonically with the shrinking of the emitter stripe width, which is different from the downscaling of the low-power (few emitter stripes) counterparts. Instead, the emitter stripe width of large-area devices ought to be appropriately up-scaled, relative to that of low-power devices, in order to optimize the RF performance of large-area SiGe power HBTs. It is also found that the influences of interconnect parasitics on the fmax and the power gain (Gmax) for common-emitter (CE) and for common-base (CB) SiGe power HBTs are different
{"title":"Influence of Interconnect Parasitics on the Lateral Scaling of SiGe Power HBTs","authors":"Guogong Wang, Hao-Chih Yuan, Z. Ma","doi":"10.1109/EMICC.2006.282685","DOIUrl":"https://doi.org/10.1109/EMICC.2006.282685","url":null,"abstract":"The influence of interconnect parasitics on the lateral scaling of emitter stripe width of large-area SiGe power heterojunction bipolar transistors (HBTs) are analytically studied and experimentally verified. It is found that, due to the increased parasitics along with the increase of device area, the maximum oscillation frequency (fmax ) of a power SiGe HBT cannot be improved monotonically with the shrinking of the emitter stripe width, which is different from the downscaling of the low-power (few emitter stripes) counterparts. Instead, the emitter stripe width of large-area devices ought to be appropriately up-scaled, relative to that of low-power devices, in order to optimize the RF performance of large-area SiGe power HBTs. It is also found that the influences of interconnect parasitics on the fmax and the power gain (Gmax) for common-emitter (CE) and for common-base (CB) SiGe power HBTs are different","PeriodicalId":269652,"journal":{"name":"2006 European Microwave Integrated Circuits Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132179676","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 : 2006-09-01DOI: 10.1109/EMICC.2006.282801
D. Resca, A. Santarelli, A. Raffo, R. Cignani, G. Vannini, F. Filicori, A. Cidronali
Electron device modelling at very high frequencies needs, as a preliminary step, the identification of suitable parasitic elements mainly describing the passive structure used for accessing the intrinsic device. However, when dealing with device modelling at millimetre-wave frequencies conventional lumped parasitic networks necessarily become less adequate in describing inherently distributed parasitic phenomena. In this paper, a distributed approach is adopted for the modelling of the parasitic network and a new identification procedure, based on electromagnetic simulation and conventional S-parameter measurements, is proposed. The intrinsic device, obtained after de-embedding from the distributed parasitic network, is particularly suitable for the extraction of accurate nonlinear models. Preliminary validation results are provided in the paper
{"title":"A distributed approach for millimetre-wave electron device modelling","authors":"D. Resca, A. Santarelli, A. Raffo, R. Cignani, G. Vannini, F. Filicori, A. Cidronali","doi":"10.1109/EMICC.2006.282801","DOIUrl":"https://doi.org/10.1109/EMICC.2006.282801","url":null,"abstract":"Electron device modelling at very high frequencies needs, as a preliminary step, the identification of suitable parasitic elements mainly describing the passive structure used for accessing the intrinsic device. However, when dealing with device modelling at millimetre-wave frequencies conventional lumped parasitic networks necessarily become less adequate in describing inherently distributed parasitic phenomena. In this paper, a distributed approach is adopted for the modelling of the parasitic network and a new identification procedure, based on electromagnetic simulation and conventional S-parameter measurements, is proposed. The intrinsic device, obtained after de-embedding from the distributed parasitic network, is particularly suitable for the extraction of accurate nonlinear models. Preliminary validation results are provided in the paper","PeriodicalId":269652,"journal":{"name":"2006 European Microwave Integrated Circuits Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128833039","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 : 2006-09-01DOI: 10.1109/EMICC.2006.282660
D. An, Bok-Hyung Lee, B. Lim, Mun-Kyo Lee, Sungchan Kim, Hyun‐Chang Park, J. Rhee
We present the high performance 94 GHz resistive mixer including IF amplifier using 0.1 mum metamorphic HEMT. For 94 GHz resistive mixer, the metamorphic HEMT of excellent characteristics was developed. The circuit performance of resistive mixer with IF amplifier shows conversion gain of 1.3 dB at LO power of 7 dBm. In this work, we fabricated the resistive mixer which has high performance using metamorphic HEMT. The fabricated resistive mixer shows the superior conversion gain than that of previous reported results
{"title":"High Performance 94 GHz Resistive Mixer Using GaAs Metamorphic HEMT Technology","authors":"D. An, Bok-Hyung Lee, B. Lim, Mun-Kyo Lee, Sungchan Kim, Hyun‐Chang Park, J. Rhee","doi":"10.1109/EMICC.2006.282660","DOIUrl":"https://doi.org/10.1109/EMICC.2006.282660","url":null,"abstract":"We present the high performance 94 GHz resistive mixer including IF amplifier using 0.1 mum metamorphic HEMT. For 94 GHz resistive mixer, the metamorphic HEMT of excellent characteristics was developed. The circuit performance of resistive mixer with IF amplifier shows conversion gain of 1.3 dB at LO power of 7 dBm. In this work, we fabricated the resistive mixer which has high performance using metamorphic HEMT. The fabricated resistive mixer shows the superior conversion gain than that of previous reported results","PeriodicalId":269652,"journal":{"name":"2006 European Microwave Integrated Circuits Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120806961","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 : 2006-09-01DOI: 10.1109/EUMC.2006.281015
F. Han, J. Wu, T. Horng
A Volterra series analysis is presented to study the package and printed circuit board (PCB) effects on the linearity of two W-CDMA upconverter MMIC designs. The first design adopts a recently popular micromixer with class-AB input stage. The second design is based on a commonly used Gilbert mixer with emitter degeneration. Both upconverter MMICs are designed to have the same adjacent channel power ratio (ACPR) in the chip-level simulation. After fabrication, packaging and testing on PCB, the micromixer-based design consumes less direct current but causes more degradation in the ACPR performance due to the influence of package and PCB when compared to the Gilbert mixer-based design. The analysis indicates that the micromixer-based upconverter MMIC is rather susceptible to the parasitic effects from the ground interconnect, and therefore it needs a better package solution with a lower ground inductance for practical use
{"title":"A Rigorous Comparison of Package and PCB Effects on Micromixer- and Gilbert Mixer-Based Upconverter MMICs","authors":"F. Han, J. Wu, T. Horng","doi":"10.1109/EUMC.2006.281015","DOIUrl":"https://doi.org/10.1109/EUMC.2006.281015","url":null,"abstract":"A Volterra series analysis is presented to study the package and printed circuit board (PCB) effects on the linearity of two W-CDMA upconverter MMIC designs. The first design adopts a recently popular micromixer with class-AB input stage. The second design is based on a commonly used Gilbert mixer with emitter degeneration. Both upconverter MMICs are designed to have the same adjacent channel power ratio (ACPR) in the chip-level simulation. After fabrication, packaging and testing on PCB, the micromixer-based design consumes less direct current but causes more degradation in the ACPR performance due to the influence of package and PCB when compared to the Gilbert mixer-based design. The analysis indicates that the micromixer-based upconverter MMIC is rather susceptible to the parasitic effects from the ground interconnect, and therefore it needs a better package solution with a lower ground inductance for practical use","PeriodicalId":269652,"journal":{"name":"2006 European Microwave Integrated Circuits Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129833391","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 : 2006-09-01DOI: 10.1109/EMICC.2006.282659
Sungchan Kim, D. An, Bok-Hyung Lee, Mun-Kyo Lee, D. Shin, J. Rhee
In this paper, millimeter-wave coplanar high gain and wideband cascode amplifiers based on metamorphic high electron mobility transistor (MHEMT) were designed and fabricated. The fabricated 100 nm gate length MHEMT devices exhibit DC characteristics with a drain current density of 471 mA/mm and an extrinsic transconductance of 845 mS/mm. The current gain cutoff frequency (fT) and the maximum oscillation frequency (fmax) are 193 GHz and 325 GHz, respectively. The matching circuit of cascode amplifier was designed for wideband characteristics using CPW (coplanar waveguide) transmission line. The one-stage amplifier showed a very wide 3 dB bandwidth of 37 GHz from 31.3 GHz to 68.3 GHz. The average S21 gain was 9.7 dB in band, with the maximum gain of 11.3 dB at 40 GHz. The two-stage amplifier had a 3 dB bandwidth of 29.5 GHz from 32.5 GHz to 62.0 GHz. The two-stage amplifier showed an excellent gain characteristic with average S21 gain of 20.4 dB in band and the maximum gain of 22.3 dB at 36.5 GHz. To our knowledge, these results have higher gain-per-stage with wider bandwidth than some other millimeter-wave amplifiers
{"title":"Wideband and High Gain Cascode Amplifier using Metamorphic HEMT for Millimeter-wave Applications","authors":"Sungchan Kim, D. An, Bok-Hyung Lee, Mun-Kyo Lee, D. Shin, J. Rhee","doi":"10.1109/EMICC.2006.282659","DOIUrl":"https://doi.org/10.1109/EMICC.2006.282659","url":null,"abstract":"In this paper, millimeter-wave coplanar high gain and wideband cascode amplifiers based on metamorphic high electron mobility transistor (MHEMT) were designed and fabricated. The fabricated 100 nm gate length MHEMT devices exhibit DC characteristics with a drain current density of 471 mA/mm and an extrinsic transconductance of 845 mS/mm. The current gain cutoff frequency (fT) and the maximum oscillation frequency (fmax) are 193 GHz and 325 GHz, respectively. The matching circuit of cascode amplifier was designed for wideband characteristics using CPW (coplanar waveguide) transmission line. The one-stage amplifier showed a very wide 3 dB bandwidth of 37 GHz from 31.3 GHz to 68.3 GHz. The average S21 gain was 9.7 dB in band, with the maximum gain of 11.3 dB at 40 GHz. The two-stage amplifier had a 3 dB bandwidth of 29.5 GHz from 32.5 GHz to 62.0 GHz. The two-stage amplifier showed an excellent gain characteristic with average S21 gain of 20.4 dB in band and the maximum gain of 22.3 dB at 36.5 GHz. To our knowledge, these results have higher gain-per-stage with wider bandwidth than some other millimeter-wave amplifiers","PeriodicalId":269652,"journal":{"name":"2006 European Microwave Integrated Circuits Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122278804","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 : 2006-09-01DOI: 10.1109/EMICC.2006.282794
A. Bessemoulin, Y. Suh, D. Richardson, S. Mahon, J. Harvey
This paper presents the performance of a 0.5-Watt Ku-band power amplifier MMIC in low cost surface mount quad flat non-leaded packages (QFN). Depending on the technology used (molded or air-cavity QFN packages), the packaged 2-stage amplifier exhibits high-gain ranging from 18- to 20 dB at Ku-band, with more than 27-dBm (500-mW) CW output power, and up to 29-dBm in saturation (800 mW) at 13.75-14.5 GHz. With a die area of only 1.5 mm2 and QFN packages being 3 mm × 3 mm, these results represents the highest output power levels reported to date for amplifier MMICs packaged in the smallest outline
{"title":"A Compact 500-mW Ku-band Power Amplifier MMIC in 3×3-mm2 Quad Flat (QFN) Packages","authors":"A. Bessemoulin, Y. Suh, D. Richardson, S. Mahon, J. Harvey","doi":"10.1109/EMICC.2006.282794","DOIUrl":"https://doi.org/10.1109/EMICC.2006.282794","url":null,"abstract":"This paper presents the performance of a 0.5-Watt Ku-band power amplifier MMIC in low cost surface mount quad flat non-leaded packages (QFN). Depending on the technology used (molded or air-cavity QFN packages), the packaged 2-stage amplifier exhibits high-gain ranging from 18- to 20 dB at Ku-band, with more than 27-dBm (500-mW) CW output power, and up to 29-dBm in saturation (800 mW) at 13.75-14.5 GHz. With a die area of only 1.5 mm2 and QFN packages being 3 mm × 3 mm, these results represents the highest output power levels reported to date for amplifier MMICs packaged in the smallest outline","PeriodicalId":269652,"journal":{"name":"2006 European Microwave Integrated Circuits Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126681490","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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