Pub Date : 2018-04-05DOI: 10.1109/WMCAS.2018.8400638
Salahuddin Tariq, D. Psychoudakis, O. Eliezer, F. Khan
A proposed antenna system for a 5th generation millimeter wave radio that employs digital beamforming is demonstrated and its measured performance is compared with simulated results. The design approach, based on a pair of identical antenna arrays that are placed in proximity to one another, violates rules of traditional beamforming antenna array design to avoid the high-complexity associated with the calibration and to simplify over-the-air (OTA) testing. The antenna arrays are realized on a multi-layer printed-circuit board (PCB) alongside the radio circuitry, and they rely on a low-loss top-layer dielectric material (Rogers 4350).
{"title":"A new approach to antenna beamforming for millimeter-wave fifth generation (5G) systems","authors":"Salahuddin Tariq, D. Psychoudakis, O. Eliezer, F. Khan","doi":"10.1109/WMCAS.2018.8400638","DOIUrl":"https://doi.org/10.1109/WMCAS.2018.8400638","url":null,"abstract":"A proposed antenna system for a 5th generation millimeter wave radio that employs digital beamforming is demonstrated and its measured performance is compared with simulated results. The design approach, based on a pair of identical antenna arrays that are placed in proximity to one another, violates rules of traditional beamforming antenna array design to avoid the high-complexity associated with the calibration and to simplify over-the-air (OTA) testing. The antenna arrays are realized on a multi-layer printed-circuit board (PCB) alongside the radio circuitry, and they rely on a low-loss top-layer dielectric material (Rogers 4350).","PeriodicalId":254840,"journal":{"name":"2018 Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125526022","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 : 2018-04-05DOI: 10.1109/WMCAS.2018.8400640
Salahuddin Tariq
High gain, large radiating structures such as multi-element antenna arrays and reflectarrays are finding an increasing number of applications to fulfil the demands of higher capacity and better coverage. For large reflectarrays, number of elements may be more than a thousand. Before fabrication, we need to model of whole reflectarray assembly in simulation software to predict its performance. Problematic part is that dimension of each element may be different, and it becomes extremely cumbersome to draw all the elements manually. To circumvent the problem, we have laid out step by step procedure that how Visual Basic (VB) code can be effectively integrated with HFSS to automate the drawing procedure of reflectarrays. As per user need, this VB script can also be extended to carry out further iterations and modifications in the design for tuning and optimization.
{"title":"Automation of reflectarrays in HFSS using visual basic scripting","authors":"Salahuddin Tariq","doi":"10.1109/WMCAS.2018.8400640","DOIUrl":"https://doi.org/10.1109/WMCAS.2018.8400640","url":null,"abstract":"High gain, large radiating structures such as multi-element antenna arrays and reflectarrays are finding an increasing number of applications to fulfil the demands of higher capacity and better coverage. For large reflectarrays, number of elements may be more than a thousand. Before fabrication, we need to model of whole reflectarray assembly in simulation software to predict its performance. Problematic part is that dimension of each element may be different, and it becomes extremely cumbersome to draw all the elements manually. To circumvent the problem, we have laid out step by step procedure that how Visual Basic (VB) code can be effectively integrated with HFSS to automate the drawing procedure of reflectarrays. As per user need, this VB script can also be extended to carry out further iterations and modifications in the design for tuning and optimization.","PeriodicalId":254840,"journal":{"name":"2018 Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133770895","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 : 2018-04-05DOI: 10.1109/WMCAS.2018.8400648
N. Tasneem, Saket R. Suri, Fana Mahbub
The area of applications for wireless power transmission is increasing rapidly, so is the need for designing efficient rectifiers to convert an AC voltage signal to a DC voltage to deliver to the load. In a wireless power transfer module, rectifier, being one of the most important components, needs to be designed in an optimized manner to provide high DC output voltage with a high efficiency from a low RF input power. In this paper, a 10-stage rectifier design using Schottky diodes and poly2 over poly capacitors in 0.5 μm standard CMOS process is presented. Simulation results show that the rectifier can convert an RF signal with an input voltage of as low as 100 mV at 7.2 MHz frequency to an output voltage of 160 mVDc. It achieves 1.55 Vdc signal for an input ac signal of 200 mV. This performance verifies the integration of the rectifier to the wireless power transfer module that would improve the overall power conversion efficiency.
无线电力传输的应用领域正在迅速增加，因此需要设计高效的整流器来将交流电压信号转换为直流电压以传递给负载。在无线电源传输模块中，整流器作为最重要的器件之一，需要进行优化设计，以在较低的射频输入功率下提供高效率的高直流输出电压。本文提出了一种采用肖特基二极管和poly2 over poly电容器，采用0.5 μm标准CMOS工艺的10级整流器设计。仿真结果表明，该整流器可将输入电压低至100 mV、频率为7.2 MHz的射频信号转换为输出电压为160 mVDc的信号。在输入200 mV的交流信号下实现1.55 Vdc的信号。这一性能验证了整流器与无线电力传输模块的集成，将提高整体电力转换效率。
{"title":"A low-power CMOS voltage boosting rectifier for wireless power transfer applications","authors":"N. Tasneem, Saket R. Suri, Fana Mahbub","doi":"10.1109/WMCAS.2018.8400648","DOIUrl":"https://doi.org/10.1109/WMCAS.2018.8400648","url":null,"abstract":"The area of applications for wireless power transmission is increasing rapidly, so is the need for designing efficient rectifiers to convert an AC voltage signal to a DC voltage to deliver to the load. In a wireless power transfer module, rectifier, being one of the most important components, needs to be designed in an optimized manner to provide high DC output voltage with a high efficiency from a low RF input power. In this paper, a 10-stage rectifier design using Schottky diodes and poly2 over poly capacitors in 0.5 μm standard CMOS process is presented. Simulation results show that the rectifier can convert an RF signal with an input voltage of as low as 100 mV at 7.2 MHz frequency to an output voltage of 160 mVDc. It achieves 1.55 Vdc signal for an input ac signal of 200 mV. This performance verifies the integration of the rectifier to the wireless power transfer module that would improve the overall power conversion efficiency.","PeriodicalId":254840,"journal":{"name":"2018 Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122578941","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}
This paper presents a simultaneous noise and distortion canceling low noise amplifier (LNA) for high-frequency ultrasound imaging applications. A feedforward noise canceling technique is developed to achieve both low noise figure (NF) and good input impedance matching (S11). The LNA also exploits the complementary characteristics of NMOS and PMOS transistors to cancel the second-order harmonic for linearity enhancement. The proposed LNA is designed in a 0.18 μm CMOS technology and exhibits a 6 dB NF and a 10 dB total harmonic distortion (THD) improvements. The LNA is specifically designed for 30–120 MHz high-frequency ultrasound transducers. At 30 MHz, the LNA achieves a NF of 2.1 dB, a voltage gain of 19 dB, and a THD of 60 dB under 1 mV peak-to-peak input. The core circuit draws 10 mA current from a 1.8 V supply.
{"title":"A wideband complementary noise and distortion canceling LNA for high-frequency ultrasound imaging applications","authors":"Yuxuan Tang, Yulang Feng, Q. Fan, Cheng Fang, Jun Zou, Jinghong Chen","doi":"10.1109/WMCAS.2018.8400635","DOIUrl":"https://doi.org/10.1109/WMCAS.2018.8400635","url":null,"abstract":"This paper presents a simultaneous noise and distortion canceling low noise amplifier (LNA) for high-frequency ultrasound imaging applications. A feedforward noise canceling technique is developed to achieve both low noise figure (NF) and good input impedance matching (S11). The LNA also exploits the complementary characteristics of NMOS and PMOS transistors to cancel the second-order harmonic for linearity enhancement. The proposed LNA is designed in a 0.18 μm CMOS technology and exhibits a 6 dB NF and a 10 dB total harmonic distortion (THD) improvements. The LNA is specifically designed for 30–120 MHz high-frequency ultrasound transducers. At 30 MHz, the LNA achieves a NF of 2.1 dB, a voltage gain of 19 dB, and a THD of 60 dB under 1 mV peak-to-peak input. The core circuit draws 10 mA current from a 1.8 V supply.","PeriodicalId":254840,"journal":{"name":"2018 Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127060534","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 : 2018-04-05DOI: 10.1109/WMCAS.2018.8400627
George Lee, B. Garner, Yang Li
Understanding how electromagnetic waves propagate on the human body is important for deployment of wireless on-body sensor systems. The aim of this study is to apply a developing simulation framework combining measurement and simulation techniques to analyze on-body wave propagation during motions involving the lower limbs.
{"title":"Simulation of dynamic electromagnetic wave propagation on humans: Lower body analysis","authors":"George Lee, B. Garner, Yang Li","doi":"10.1109/WMCAS.2018.8400627","DOIUrl":"https://doi.org/10.1109/WMCAS.2018.8400627","url":null,"abstract":"Understanding how electromagnetic waves propagate on the human body is important for deployment of wireless on-body sensor systems. The aim of this study is to apply a developing simulation framework combining measurement and simulation techniques to analyze on-body wave propagation during motions involving the lower limbs.","PeriodicalId":254840,"journal":{"name":"2018 Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122989580","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 : 2018-04-05DOI: 10.1109/WMCAS.2018.8400620
D. Biswas, M. Sinclair, J. Hyde, I. Mahbub
Optogenetics is the control and monitoring of genetically modified neurons that are responsive to light. It has opened the door for neuroscience research by providing a means to understand the neural circuit dysfunctions such as mood disorders, addiction, and Parkinson's disease. With the growing demand for biomedical implants, the need for a wireless power transfer (WPT) module is also increasing. An essential part of optogenetic implants is the power source of the device. A wireless optogenetic implant requires enough voltage and current to power an LED to stimulate the neurons. In this paper, a WPT module with a transmitter and a compact receiver module are presented. The receiver module contains a miniaturized 6 × 6 mm2 receiver antenna, a Schottky diode, and a mini-LED. The proposed WPT scheme utilizes near-field communication and inductive power transmission at 7.15 MHz frequency. Simulation results using High Frequency Structure Simulator (HFSS) show that the receiver antenna achieves up to a −15.37 dB return loss (Sii) at the resonating frequency. The fabricated WPT system transfers 500 mVpp to the receiver module at 5 mm distance for an input power of 0 dBm. The received power is rectified to provide an average 200 mV DC to turn on a mini-LED. The preliminary simulation and measurement results of the proposed WPT module show a better prospect for future optogenetics based applications.
{"title":"An NFC (near-field communication) based wireless power transfer system design with miniaturized receiver coil for optogenetic implants","authors":"D. Biswas, M. Sinclair, J. Hyde, I. Mahbub","doi":"10.1109/WMCAS.2018.8400620","DOIUrl":"https://doi.org/10.1109/WMCAS.2018.8400620","url":null,"abstract":"Optogenetics is the control and monitoring of genetically modified neurons that are responsive to light. It has opened the door for neuroscience research by providing a means to understand the neural circuit dysfunctions such as mood disorders, addiction, and Parkinson's disease. With the growing demand for biomedical implants, the need for a wireless power transfer (WPT) module is also increasing. An essential part of optogenetic implants is the power source of the device. A wireless optogenetic implant requires enough voltage and current to power an LED to stimulate the neurons. In this paper, a WPT module with a transmitter and a compact receiver module are presented. The receiver module contains a miniaturized 6 × 6 mm2 receiver antenna, a Schottky diode, and a mini-LED. The proposed WPT scheme utilizes near-field communication and inductive power transmission at 7.15 MHz frequency. Simulation results using High Frequency Structure Simulator (HFSS) show that the receiver antenna achieves up to a −15.37 dB return loss (Sii) at the resonating frequency. The fabricated WPT system transfers 500 mVpp to the receiver module at 5 mm distance for an input power of 0 dBm. The received power is rectified to provide an average 200 mV DC to turn on a mini-LED. The preliminary simulation and measurement results of the proposed WPT module show a better prospect for future optogenetics based applications.","PeriodicalId":254840,"journal":{"name":"2018 Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133215573","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 : 2018-04-01DOI: 10.1109/WMCAS.2018.8400651
Lucilia Hays, Austin Egbert, Zachary Hays, C. Baylis, R. Marks, Christopher Kappelmann, E. Viveiros
Frequency-agile wireless transmitters require tunable power amplifiers that can reconfigure to maximize gain, efficiency, and spectral performance at changing operating frequencies and spectral output requirements. However, stability of the amplifier must be maintained through the reconfiguration process. This paper presents a method for predicting potential instability during a real-time load impedance gain optimization. For each candidate load reflection coefficient, gain is measured at each of four neighboring points, and the acceleration of the gain is calculated. When the acceleration becomes positive, the likelihood of potential instability is detected, and the optimization is terminated to achieve high gain while remaining stable. This method is demonstrated for two different devices in simulation and measurement. While initially innovated for application in reconfigurable devices, this method is also expected to be useful in maintaining stability during bench-top load-pull measurements.
{"title":"Real-time instability detection for a reconfigurable power amplifier","authors":"Lucilia Hays, Austin Egbert, Zachary Hays, C. Baylis, R. Marks, Christopher Kappelmann, E. Viveiros","doi":"10.1109/WMCAS.2018.8400651","DOIUrl":"https://doi.org/10.1109/WMCAS.2018.8400651","url":null,"abstract":"Frequency-agile wireless transmitters require tunable power amplifiers that can reconfigure to maximize gain, efficiency, and spectral performance at changing operating frequencies and spectral output requirements. However, stability of the amplifier must be maintained through the reconfiguration process. This paper presents a method for predicting potential instability during a real-time load impedance gain optimization. For each candidate load reflection coefficient, gain is measured at each of four neighboring points, and the acceleration of the gain is calculated. When the acceleration becomes positive, the likelihood of potential instability is detected, and the optimization is terminated to achieve high gain while remaining stable. This method is demonstrated for two different devices in simulation and measurement. While initially innovated for application in reconfigurable devices, this method is also expected to be useful in maintaining stability during bench-top load-pull measurements.","PeriodicalId":254840,"journal":{"name":"2018 Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125391259","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 : 2018-04-01DOI: 10.1109/WMCAS.2018.8400647
J. Goossen, Joonwan Kim, Samuel van der Hoeven
The Versatile ADS-B Communication System (VACS) is a card that can be mounted on an unmanned aerial vehicle (UAV) to transmit an Automatic Dependent Surveillance Broadcast (ADS-B) signal. The lightweight and cost-effective ADS-B transmitter can increase UAV visibility to aircraft. Weighing only 100 grams, the card can be easily carried by most UAVs while maintaining affordability for hobbyists. The small, lightweight ADS-B transmitter mounted on a UAV is able to communicate the location, altitude, and heading data of a UAV to any nearby aircraft, drastically reducing the likelihood of a tragic collision. A prototype VACS has been successfully designed and tested.
{"title":"Development of a versatile ADS-B communications system","authors":"J. Goossen, Joonwan Kim, Samuel van der Hoeven","doi":"10.1109/WMCAS.2018.8400647","DOIUrl":"https://doi.org/10.1109/WMCAS.2018.8400647","url":null,"abstract":"The Versatile ADS-B Communication System (VACS) is a card that can be mounted on an unmanned aerial vehicle (UAV) to transmit an Automatic Dependent Surveillance Broadcast (ADS-B) signal. The lightweight and cost-effective ADS-B transmitter can increase UAV visibility to aircraft. Weighing only 100 grams, the card can be easily carried by most UAVs while maintaining affordability for hobbyists. The small, lightweight ADS-B transmitter mounted on a UAV is able to communicate the location, altitude, and heading data of a UAV to any nearby aircraft, drastically reducing the likelihood of a tragic collision. A prototype VACS has been successfully designed and tested.","PeriodicalId":254840,"journal":{"name":"2018 Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131901087","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 : 2018-04-01DOI: 10.1109/WMCAS.2018.8400632
M. Mustafa
A systematic method for finding modes in planar layered media environment based on Cauchy Integration Method is presented. A rigorous approach for treating the branch cuts discontinuities and branch points singularities is introduced. The current formulation is applicable for uniaxial media and extended to allow the introduction of arbitrary 2D conductive sheets between the layers such as Graphene. A pole-free Dispersion Function was developed for all combinations of boundary terminations: open, PEC, PMC and impedance. Numerical examples are provided.
{"title":"Modal analysis in planar layered structures with conductive sheets using Cauchy integration method","authors":"M. Mustafa","doi":"10.1109/WMCAS.2018.8400632","DOIUrl":"https://doi.org/10.1109/WMCAS.2018.8400632","url":null,"abstract":"A systematic method for finding modes in planar layered media environment based on Cauchy Integration Method is presented. A rigorous approach for treating the branch cuts discontinuities and branch points singularities is introduced. The current formulation is applicable for uniaxial media and extended to allow the introduction of arbitrary 2D conductive sheets between the layers such as Graphene. A pole-free Dispersion Function was developed for all combinations of boundary terminations: open, PEC, PMC and impedance. Numerical examples are provided.","PeriodicalId":254840,"journal":{"name":"2018 Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115926052","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 : 2018-04-01DOI: 10.1109/WMCAS.2018.8400633
Heechai Kang, Venkata S. Rayudu, Ki Yong Kim, R. Gharpurey
A delay-locked loop (DLL) based RF-PWM generator is proposed for broadband signal modulation. The approach can be applied to a Cartesian transmitter in combination with a switching output stage. The proposed transmitter architecture is verified in a macro-model simulation, using a signal bandwidth of 40 MHz, at a carrier frequency of 2 GHz.
{"title":"RF pulse-width-modulation generator employing a delay-locked-loop for a wideband transmitter","authors":"Heechai Kang, Venkata S. Rayudu, Ki Yong Kim, R. Gharpurey","doi":"10.1109/WMCAS.2018.8400633","DOIUrl":"https://doi.org/10.1109/WMCAS.2018.8400633","url":null,"abstract":"A delay-locked loop (DLL) based RF-PWM generator is proposed for broadband signal modulation. The approach can be applied to a Cartesian transmitter in combination with a switching output stage. The proposed transmitter architecture is verified in a macro-model simulation, using a signal bandwidth of 40 MHz, at a carrier frequency of 2 GHz.","PeriodicalId":254840,"journal":{"name":"2018 Texas Symposium on Wireless and Microwave Circuits and Systems (WMCS)","volume":"266 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116043910","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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