Pub Date : 2001-10-21DOI: 10.1109/GAAS.2001.964357
N. Suematsu, S. Shinjo
Aiming for 2-5GHz band transceiver system on a chip, the integration of RF section has been developed by using conventional CMOS/BiCMOS (SiGeCMOS) process. The attempts to integrate power amplifiers (PA's) have been successful for low transmit power system such as Bluetooth, but these attempts are very limited due to the poor power handling capability of FET's in CMOS and the distortion characteristics of BJT's(HBT's) in BiCMOS. From the point of view of a circuit designer, this paper reviews the recent research activities of CMOS/BiCMOS PA's in Japan, and also describes the details of (1) the feasibility study of PA's using conventional CMOS process, and (2) the circuitry trials of distortion reduction for BJT(HBT) PA's.
{"title":"CMOS/BiCMOS power amplifier technology trend in Japan","authors":"N. Suematsu, S. Shinjo","doi":"10.1109/GAAS.2001.964357","DOIUrl":"https://doi.org/10.1109/GAAS.2001.964357","url":null,"abstract":"Aiming for 2-5GHz band transceiver system on a chip, the integration of RF section has been developed by using conventional CMOS/BiCMOS (SiGeCMOS) process. The attempts to integrate power amplifiers (PA's) have been successful for low transmit power system such as Bluetooth, but these attempts are very limited due to the poor power handling capability of FET's in CMOS and the distortion characteristics of BJT's(HBT's) in BiCMOS. From the point of view of a circuit designer, this paper reviews the recent research activities of CMOS/BiCMOS PA's in Japan, and also describes the details of (1) the feasibility study of PA's using conventional CMOS process, and (2) the circuitry trials of distortion reduction for BJT(HBT) PA's.","PeriodicalId":269944,"journal":{"name":"GaAs IC Symposium. IEEE Gallium Arsenide Integrated Circuit Symposium. 23rd Annual Technical Digest 2001 (Cat. No.01CH37191)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131322199","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 : 2001-10-21DOI: 10.1109/GAAS.2001.964340
T. Nakagawa, M. Kawashima, H. Hayashi, K. Araki
A wideband direct conversion receiver for multi-band applications is presented. The developed receiver consists of one quadrature downconverter, one low-noise amplifier (LNA), and two voltage-controlled oscillators (VCOs). The key component ICs are fabricated on GaAs and Si substrates. The receiver can receive three different frequency bands, i.e. the 900 MHz band, 1.9 GHz band, and 2.4 GHz band.
{"title":"A 0.9-2.5 GHz wideband direct conversion receiver for multi-band applications","authors":"T. Nakagawa, M. Kawashima, H. Hayashi, K. Araki","doi":"10.1109/GAAS.2001.964340","DOIUrl":"https://doi.org/10.1109/GAAS.2001.964340","url":null,"abstract":"A wideband direct conversion receiver for multi-band applications is presented. The developed receiver consists of one quadrature downconverter, one low-noise amplifier (LNA), and two voltage-controlled oscillators (VCOs). The key component ICs are fabricated on GaAs and Si substrates. The receiver can receive three different frequency bands, i.e. the 900 MHz band, 1.9 GHz band, and 2.4 GHz band.","PeriodicalId":269944,"journal":{"name":"GaAs IC Symposium. IEEE Gallium Arsenide Integrated Circuit Symposium. 23rd Annual Technical Digest 2001 (Cat. No.01CH37191)","volume":"43 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130499256","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 : 2001-10-21DOI: 10.1109/GAAS.2001.964367
Ryan Welch, Tom Jenkins, Bob Neidhard, Lois Kehias, Tony Quach, P. Watson, Rick Worley, Mike Barsky, Randy Sandhu, Mike Wojtowicz
This work reports on efforts to demonstrate AlGaN/GaN Low Noise Amplifiers (LNAs) in epitaxial material designed to build power transistors. The hybrid LNA circuit produced a noise figure of 3 dB, a gain of 8.5 dB, an input return loss of -6.5 dB and an output return loss of -9 dB at 4 GHz. Further, devices in an enhanced process have improved noise characteristics and more realizable match conditions. These device enhancements will enable robust X-band LNA demonstrations.
{"title":"Low noise hybrid amplifier using AlGaN/GaN power HEMT devices","authors":"Ryan Welch, Tom Jenkins, Bob Neidhard, Lois Kehias, Tony Quach, P. Watson, Rick Worley, Mike Barsky, Randy Sandhu, Mike Wojtowicz","doi":"10.1109/GAAS.2001.964367","DOIUrl":"https://doi.org/10.1109/GAAS.2001.964367","url":null,"abstract":"This work reports on efforts to demonstrate AlGaN/GaN Low Noise Amplifiers (LNAs) in epitaxial material designed to build power transistors. The hybrid LNA circuit produced a noise figure of 3 dB, a gain of 8.5 dB, an input return loss of -6.5 dB and an output return loss of -9 dB at 4 GHz. Further, devices in an enhanced process have improved noise characteristics and more realizable match conditions. These device enhancements will enable robust X-band LNA demonstrations.","PeriodicalId":269944,"journal":{"name":"GaAs IC Symposium. IEEE Gallium Arsenide Integrated Circuit Symposium. 23rd Annual Technical Digest 2001 (Cat. No.01CH37191)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125198880","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 : 2001-10-21DOI: 10.1109/GAAS.2001.964380
T. Quach, P. Watson, W. Okamura, E. Kaneshiro, A. Gutierrez-Aitken, T. Block, J. Eldredge, T. Jenkins, L. Kehias, A. Oki, D. Sawdai, R. Welch, R. Worley
We report on a broadband high efficiency power amplifier using Indium Phosphide (InP) double heterojunction bipolar transistor (DHBT) technology. The amplifier demonstrated a record bandwidth for a class-E power amplifier at X-band. This circuit achieved 49-58% PAE, 18.5-23.9 dBm output power, and 9.6-10.5 dB gain across 9-11 GHz.
{"title":"Broadband class-E power amplifier for space radar application","authors":"T. Quach, P. Watson, W. Okamura, E. Kaneshiro, A. Gutierrez-Aitken, T. Block, J. Eldredge, T. Jenkins, L. Kehias, A. Oki, D. Sawdai, R. Welch, R. Worley","doi":"10.1109/GAAS.2001.964380","DOIUrl":"https://doi.org/10.1109/GAAS.2001.964380","url":null,"abstract":"We report on a broadband high efficiency power amplifier using Indium Phosphide (InP) double heterojunction bipolar transistor (DHBT) technology. The amplifier demonstrated a record bandwidth for a class-E power amplifier at X-band. This circuit achieved 49-58% PAE, 18.5-23.9 dBm output power, and 9.6-10.5 dB gain across 9-11 GHz.","PeriodicalId":269944,"journal":{"name":"GaAs IC Symposium. IEEE Gallium Arsenide Integrated Circuit Symposium. 23rd Annual Technical Digest 2001 (Cat. No.01CH37191)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115498677","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 : 2001-10-21DOI: 10.1109/GAAS.2001.964392
H. Chiu, Shih-Cheng Yang, Y. Chan
A high power-added efficiency Al/sub 0.5/Ga/sub 0.5/As/InGaAs enhancement-mode pHEMTs with benzocyclobutene (BCB) passivated layer are fabricated and characterized. This passivation technology takes advantages of the low dielectric permittivity (2.7) and a low loss tangent (0.0008), which simplifies the passivation process for microwave power device. In this work, we not only suppress the drain-source breakdown voltage but also improve the device power performance under a high input power swing by using a BCB passivation layer. The passivated 1.0 /spl mu/m-long gate pHEMTs exhibit a higher off-state performance than unpassivated ones. The maximum output power under a 2.4 GHz operation is 118 mW/mm, with a linear power gain of 11.1 dB, and a power-added efficiency of 60%. These characteristics demonstrate a great potential for BCB passivated E-mode pHEMTs on the large-signal microwave power device applications.
采用苯并环丁烯(BCB)钝化层制备了高功率增效Al/sub 0.5/Ga/sub 0.5/As/InGaAs增强模式pHEMTs并进行了表征。该钝化技术利用低介电常数(2.7)和低损耗正切(0.0008)的优点，简化了微波功率器件的钝化过程。在这项工作中，我们不仅抑制了漏源击穿电压，而且通过使用BCB钝化层提高了器件在高输入功率摆幅下的功率性能。钝化后的1.0 /spl μ l /m长的栅极phemt比未钝化的栅极phemt表现出更高的非稳态性能。2.4 GHz工作下的最大输出功率为118 mW/mm，线性功率增益为11.1 dB，功率附加效率为60%。这些特性证明了BCB钝化e模phemt在大信号微波功率器件上的巨大应用潜力。
{"title":"Low-k BCB passivated Al/sub 0.5/Ga/sub 0.5/As/In/sub 0.15/Ga/sub 0.85/As enhancement-mode pHEMTs","authors":"H. Chiu, Shih-Cheng Yang, Y. Chan","doi":"10.1109/GAAS.2001.964392","DOIUrl":"https://doi.org/10.1109/GAAS.2001.964392","url":null,"abstract":"A high power-added efficiency Al/sub 0.5/Ga/sub 0.5/As/InGaAs enhancement-mode pHEMTs with benzocyclobutene (BCB) passivated layer are fabricated and characterized. This passivation technology takes advantages of the low dielectric permittivity (2.7) and a low loss tangent (0.0008), which simplifies the passivation process for microwave power device. In this work, we not only suppress the drain-source breakdown voltage but also improve the device power performance under a high input power swing by using a BCB passivation layer. The passivated 1.0 /spl mu/m-long gate pHEMTs exhibit a higher off-state performance than unpassivated ones. The maximum output power under a 2.4 GHz operation is 118 mW/mm, with a linear power gain of 11.1 dB, and a power-added efficiency of 60%. These characteristics demonstrate a great potential for BCB passivated E-mode pHEMTs on the large-signal microwave power device applications.","PeriodicalId":269944,"journal":{"name":"GaAs IC Symposium. IEEE Gallium Arsenide Integrated Circuit Symposium. 23rd Annual Technical Digest 2001 (Cat. No.01CH37191)","volume":"129 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126865747","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 : 2001-10-21DOI: 10.1109/GAAS.2001.964334
P.M. Smith, K. Nichols, W. Kong, L. MtPleasant, D. Pritchard, R. Lender, J. Fisher, R. Actis, D. Dugas, D. Meharry, A. Swanson
This paper presents an overview of the rapid progress being made in the development of InP HEMT devices and circuits for high frequency analog applications. Although widespread use of InP HEMTs has to date been limited by their comparatively high cost, commercialization now appears to be inevitable due to recent progress on two parallel fronts-the development of metamorphic HEMTs (MHEMTs) and the scaling of InP substrates to larger sizes (4- and 6-inch).
{"title":"Advances in InP HEMT technology for high frequency applications","authors":"P.M. Smith, K. Nichols, W. Kong, L. MtPleasant, D. Pritchard, R. Lender, J. Fisher, R. Actis, D. Dugas, D. Meharry, A. Swanson","doi":"10.1109/GAAS.2001.964334","DOIUrl":"https://doi.org/10.1109/GAAS.2001.964334","url":null,"abstract":"This paper presents an overview of the rapid progress being made in the development of InP HEMT devices and circuits for high frequency analog applications. Although widespread use of InP HEMTs has to date been limited by their comparatively high cost, commercialization now appears to be inevitable due to recent progress on two parallel fronts-the development of metamorphic HEMTs (MHEMTs) and the scaling of InP substrates to larger sizes (4- and 6-inch).","PeriodicalId":269944,"journal":{"name":"GaAs IC Symposium. IEEE Gallium Arsenide Integrated Circuit Symposium. 23rd Annual Technical Digest 2001 (Cat. No.01CH37191)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131432134","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 : 2001-10-21DOI: 10.1109/GAAS.2001.964379
R. Tayrani
This paper describes what is believed to be the first successful design and fabrication of a broadband monolithic high efficiency class-E driver amplifier that operates at X-band and employs a 0.3 /spl mu/m /spl times/600 /spl mu/m pHEMT device. The amplifier's measured performance shows a peak Power Added Efficiency (PAE) of 63% at 10.6 GHz and a constant output power of greater than 24 dBm together with a gain of 10 dB over 9-11 GHz.
{"title":"A monolithic X-band class-E power amplifier","authors":"R. Tayrani","doi":"10.1109/GAAS.2001.964379","DOIUrl":"https://doi.org/10.1109/GAAS.2001.964379","url":null,"abstract":"This paper describes what is believed to be the first successful design and fabrication of a broadband monolithic high efficiency class-E driver amplifier that operates at X-band and employs a 0.3 /spl mu/m /spl times/600 /spl mu/m pHEMT device. The amplifier's measured performance shows a peak Power Added Efficiency (PAE) of 63% at 10.6 GHz and a constant output power of greater than 24 dBm together with a gain of 10 dB over 9-11 GHz.","PeriodicalId":269944,"journal":{"name":"GaAs IC Symposium. IEEE Gallium Arsenide Integrated Circuit Symposium. 23rd Annual Technical Digest 2001 (Cat. No.01CH37191)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114764353","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 : 2001-10-21DOI: 10.1109/GAAS.2001.964335
H. Darabi, S. Khorram, E. Chien, M. Pan, S. Wu, S. Moloudi, J. Leete, J. Rael, M. Syed, R. Lee, P. Kilcoyne, B. Ibrahim, M. Rofougaran, A. Rofougaran
Bluetooth is a communication protocol enabling low-cost, short-range radio links between mobile phones, mobile PCs, and other portable devices. The Bluetooth standard specifies a 2.4 GHz; frequency-hopped, spread-spectrum system that supports a data rate of 1 Mb/s. This paper describes a low-cost, low-power, and highly integrated solution for 2.4 GHz short-range radio applications, such as Bluetooth.
{"title":"A fully integrated transceiver for Bluetooth","authors":"H. Darabi, S. Khorram, E. Chien, M. Pan, S. Wu, S. Moloudi, J. Leete, J. Rael, M. Syed, R. Lee, P. Kilcoyne, B. Ibrahim, M. Rofougaran, A. Rofougaran","doi":"10.1109/GAAS.2001.964335","DOIUrl":"https://doi.org/10.1109/GAAS.2001.964335","url":null,"abstract":"Bluetooth is a communication protocol enabling low-cost, short-range radio links between mobile phones, mobile PCs, and other portable devices. The Bluetooth standard specifies a 2.4 GHz; frequency-hopped, spread-spectrum system that supports a data rate of 1 Mb/s. This paper describes a low-cost, low-power, and highly integrated solution for 2.4 GHz short-range radio applications, such as Bluetooth.","PeriodicalId":269944,"journal":{"name":"GaAs IC Symposium. IEEE Gallium Arsenide Integrated Circuit Symposium. 23rd Annual Technical Digest 2001 (Cat. No.01CH37191)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122924651","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 : 2001-10-21DOI: 10.1109/GAAS.2001.964385
E. Gebara, S. Nuttinck, M. R. Murti, D. Heo, M. Harris, J. Laskar
We present a complete on-wafer characterization of a GaAs power MESFET (L/sub g/=0.6 /spl mu/m, W/sub g/=300 /spl mu/m) at various temperature of operation. DC-IV, small-signal, power and noise parameters measurements are achieved at temperatures from 18 K to 300 K. The transition between small-signal and large-signal mode of operation is studied, highlighting the importance of load-pull measurements, and the caution that must be considered when applying small-signal results to large-signal mode of operation. Power measurements were achieved at an optimal bias condition to take into account the positive Temperature Coefficient (TC) that the On Breakdown Voltage exhibits. Results demonstrate performance improvements, when the device operates at reduced lattice temperature, in output power, power-added efficiency, intermodulation products and noise parameters. This analysis technique provides a path for developing robust temperature dependent large-signal models.
{"title":"Temperature-dependent small-signal and power and noise characterization of GaAs power FETs","authors":"E. Gebara, S. Nuttinck, M. R. Murti, D. Heo, M. Harris, J. Laskar","doi":"10.1109/GAAS.2001.964385","DOIUrl":"https://doi.org/10.1109/GAAS.2001.964385","url":null,"abstract":"We present a complete on-wafer characterization of a GaAs power MESFET (L/sub g/=0.6 /spl mu/m, W/sub g/=300 /spl mu/m) at various temperature of operation. DC-IV, small-signal, power and noise parameters measurements are achieved at temperatures from 18 K to 300 K. The transition between small-signal and large-signal mode of operation is studied, highlighting the importance of load-pull measurements, and the caution that must be considered when applying small-signal results to large-signal mode of operation. Power measurements were achieved at an optimal bias condition to take into account the positive Temperature Coefficient (TC) that the On Breakdown Voltage exhibits. Results demonstrate performance improvements, when the device operates at reduced lattice temperature, in output power, power-added efficiency, intermodulation products and noise parameters. This analysis technique provides a path for developing robust temperature dependent large-signal models.","PeriodicalId":269944,"journal":{"name":"GaAs IC Symposium. IEEE Gallium Arsenide Integrated Circuit Symposium. 23rd Annual Technical Digest 2001 (Cat. No.01CH37191)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127831903","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 : 2001-10-21DOI: 10.1109/GAAS.2001.964346
B. Mayampurath, A. Wu, A. Armstrong
A 12-channel, 2.5 Gb/s, receiver IC for parallel optical interconnect is described. Each channel contains a Metal-Semiconductor-Metal Photodetector (MSM PD), Transimpedance Amplifier (TIA), Limiting Amplifier (LA), Output Buffer (OB) and Loss of Signal Detector (LOS). The chip was designed and fabricated in a 0.4 /spl mu/m GaAs MESFET process. Using a 3.3 V power supply, the chip typically consumes 600 mA, and each channel provides 400 mV differential outputs for input optical power more than -20 dBm. Typical single channel sensitivity is -19.5 dBm. Details of the chip design and layout and measured results are presented.
{"title":"A 12-channel 2.5 Gb/s receiver IC for parallel optical interconnect","authors":"B. Mayampurath, A. Wu, A. Armstrong","doi":"10.1109/GAAS.2001.964346","DOIUrl":"https://doi.org/10.1109/GAAS.2001.964346","url":null,"abstract":"A 12-channel, 2.5 Gb/s, receiver IC for parallel optical interconnect is described. Each channel contains a Metal-Semiconductor-Metal Photodetector (MSM PD), Transimpedance Amplifier (TIA), Limiting Amplifier (LA), Output Buffer (OB) and Loss of Signal Detector (LOS). The chip was designed and fabricated in a 0.4 /spl mu/m GaAs MESFET process. Using a 3.3 V power supply, the chip typically consumes 600 mA, and each channel provides 400 mV differential outputs for input optical power more than -20 dBm. Typical single channel sensitivity is -19.5 dBm. Details of the chip design and layout and measured results are presented.","PeriodicalId":269944,"journal":{"name":"GaAs IC Symposium. IEEE Gallium Arsenide Integrated Circuit Symposium. 23rd Annual Technical Digest 2001 (Cat. No.01CH37191)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130451068","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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