Pub Date : 2015-12-01DOI: 10.1109/IMARC.2015.7411416
S. Chaturvedi, Manuraj, S. Bhalke, Vijesh Arora, S. L. Badnikar, B. K. Sehgal
This paper presents the design and development of a compact C-band down converter realized in a 12mm×12mm surface mount metal ceramic package. The size reduction has been achieved by development of compact sized MMIC components required for the receiver, viz., a double balanced mixer, a voltage controlled oscillator with on-chip varactor and RF and IF amplifiers. All the MMICs have been designed and fabricated using indigenously developed 0.7μm GaAs MESFET (G7A) technology at GAETEC. The receiver works in a frequency range of 5.0-6.0 GHz and produces down converted signal in 500-1500 MHz band when beaten with internal LO of the receiver, operated at 4.5 GHz. The conversion gain of the receiver is 27dB with a noise figure of 5dB. The RF-IF and LO-IF isolation of better than 25dB is achieved though EM optimized placement of MMICs and isolation barriers inside the package.
{"title":"A compact C-band down converter SiP with integrated LO in a metal ceramic package","authors":"S. Chaturvedi, Manuraj, S. Bhalke, Vijesh Arora, S. L. Badnikar, B. K. Sehgal","doi":"10.1109/IMARC.2015.7411416","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411416","url":null,"abstract":"This paper presents the design and development of a compact C-band down converter realized in a 12mm×12mm surface mount metal ceramic package. The size reduction has been achieved by development of compact sized MMIC components required for the receiver, viz., a double balanced mixer, a voltage controlled oscillator with on-chip varactor and RF and IF amplifiers. All the MMICs have been designed and fabricated using indigenously developed 0.7μm GaAs MESFET (G7A) technology at GAETEC. The receiver works in a frequency range of 5.0-6.0 GHz and produces down converted signal in 500-1500 MHz band when beaten with internal LO of the receiver, operated at 4.5 GHz. The conversion gain of the receiver is 27dB with a noise figure of 5dB. The RF-IF and LO-IF isolation of better than 25dB is achieved though EM optimized placement of MMICs and isolation barriers inside the package.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133144896","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 : 2015-12-01DOI: 10.1109/IMARC.2015.7411397
B. Biswas, G. Kumar
This paper presents design & development of a 47 GHz, single-ended, low conversion loss, Monolithic Microwave Integrated Circuit (MMIC) frequency tripler using 0.15pm GaAs/InGaAs/AlGaAs pseudomorphic High Electron Mobility Transistor (pHEMT). Fabricated chip size is 1.5mm × 2.0mm. The successful first run fabrication of the MMIC has achieved 3.5 dB of conversion loss at 47 GHz for 5 dBm of input power at 15.67 GHz. The circuit consumes only 35 mW of dc power, while output power flatness is within 2 dB over 8.5% frequency bandwidth. Fundamental, second, and fourth harmonic rejection is about 31 dBc, 27 dBc, and 28 dBc, respectively. Output spectrum obtained is highly stable and of high spectral purity. Therefore, the tripler becomes suitable for Millimeter Wave (MMW) transceiver applications.
{"title":"A 47 GHz power efficient MMIC tripler with low conversion loss","authors":"B. Biswas, G. Kumar","doi":"10.1109/IMARC.2015.7411397","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411397","url":null,"abstract":"This paper presents design & development of a 47 GHz, single-ended, low conversion loss, Monolithic Microwave Integrated Circuit (MMIC) frequency tripler using 0.15pm GaAs/InGaAs/AlGaAs pseudomorphic High Electron Mobility Transistor (pHEMT). Fabricated chip size is 1.5mm × 2.0mm. The successful first run fabrication of the MMIC has achieved 3.5 dB of conversion loss at 47 GHz for 5 dBm of input power at 15.67 GHz. The circuit consumes only 35 mW of dc power, while output power flatness is within 2 dB over 8.5% frequency bandwidth. Fundamental, second, and fourth harmonic rejection is about 31 dBc, 27 dBc, and 28 dBc, respectively. Output spectrum obtained is highly stable and of high spectral purity. Therefore, the tripler becomes suitable for Millimeter Wave (MMW) transceiver applications.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131996915","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 : 2015-12-01DOI: 10.1109/IMARC.2015.7411406
Akash Agrawal, K. Vinoy
In this paper microstrip coupled line band pass filters using quasi minkowski fractal geometry is studied. Although conventional microstrip coupled line filters are popular for RF front ends, their large 2nd harmonic causes the shape of the pass band to be asymmetric in the upper band and it deteriorates the skirt properties. The 2nd harmonic can be completely suppressed using fractal geometry and making the skirt properties symmetric. It is achieved by varying the aspect ratio of the fractal geometry and finding the aspect ratio for which the second harmonic is completely suppressed. The above technique is validated by applying it to three different substrates. The performance of the filter is evaluated using ADS. Results show that the proposed filter possesses good return loss and transmission response enabling their use in a variety of wireless communication applications.
{"title":"Microstrip coupled line bandpass filter using quasi minkowski fractal shape for suppression of the second harmonic","authors":"Akash Agrawal, K. Vinoy","doi":"10.1109/IMARC.2015.7411406","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411406","url":null,"abstract":"In this paper microstrip coupled line band pass filters using quasi minkowski fractal geometry is studied. Although conventional microstrip coupled line filters are popular for RF front ends, their large 2nd harmonic causes the shape of the pass band to be asymmetric in the upper band and it deteriorates the skirt properties. The 2nd harmonic can be completely suppressed using fractal geometry and making the skirt properties symmetric. It is achieved by varying the aspect ratio of the fractal geometry and finding the aspect ratio for which the second harmonic is completely suppressed. The above technique is validated by applying it to three different substrates. The performance of the filter is evaluated using ADS. Results show that the proposed filter possesses good return loss and transmission response enabling their use in a variety of wireless communication applications.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127788451","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 : 2015-12-01DOI: 10.1109/IMARC.2015.7411420
Tian-Wei Huang
This paper reviews recent digitally calibration and IQ mismatch compensation techniques. The phase control modeling of phase shifter or modulator design is the most challenging task in high-speed communications. All these built-in self-calibration and auto-switching functions are innovated to pave the road to the next-generation millimeter-wave 5G mobile smart RFIC.
{"title":"Smart RFIC: Millimeter-wave gigabit transceivers with digitally-enabled built-in self-calibration and auto-switching functions: The challenge of phase control modeling in phase shifter design","authors":"Tian-Wei Huang","doi":"10.1109/IMARC.2015.7411420","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411420","url":null,"abstract":"This paper reviews recent digitally calibration and IQ mismatch compensation techniques. The phase control modeling of phase shifter or modulator design is the most challenging task in high-speed communications. All these built-in self-calibration and auto-switching functions are innovated to pave the road to the next-generation millimeter-wave 5G mobile smart RFIC.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133157864","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 : 2015-12-01DOI: 10.1109/IMARC.2015.7411389
Nagendra Kushwaha, Raj Kumar
In this paper a modified cross dipole Frequency Selective Surface (FSS) is utilized to increase the gain of a Circular Polarized (CP) antenna. The antenna is a Coplanar Waveguide (CPW) fed structure with modified Z-shaped radiating element. The FSS is used as a reflector. It is used to enhance the Right Handed Circular polarization (RHCP) gain and making antenna nearly unidirectional. The overall size of the antenna with FSS is 1.1λ0 × 1.1λ0 × 0.2λ0. The Antenna with FSS has an impedance bandwidth of 109 % (2.1-5 GHz) and Axial Ratio Bandwidth (ARBW) of 55.7 % (2.2-3.9 GHz). The antenna along with FSS has a peak boresight gain of 7.3 dB. The radiation patterns and Gains of antenna with and without FSS are also compared to discuss the effect of FSS on antenna performance.
{"title":"On the gain enhancement of a wideband CPW-Fed circularly polarized antenna using FSS","authors":"Nagendra Kushwaha, Raj Kumar","doi":"10.1109/IMARC.2015.7411389","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411389","url":null,"abstract":"In this paper a modified cross dipole Frequency Selective Surface (FSS) is utilized to increase the gain of a Circular Polarized (CP) antenna. The antenna is a Coplanar Waveguide (CPW) fed structure with modified Z-shaped radiating element. The FSS is used as a reflector. It is used to enhance the Right Handed Circular polarization (RHCP) gain and making antenna nearly unidirectional. The overall size of the antenna with FSS is 1.1λ0 × 1.1λ0 × 0.2λ0. The Antenna with FSS has an impedance bandwidth of 109 % (2.1-5 GHz) and Axial Ratio Bandwidth (ARBW) of 55.7 % (2.2-3.9 GHz). The antenna along with FSS has a peak boresight gain of 7.3 dB. The radiation patterns and Gains of antenna with and without FSS are also compared to discuss the effect of FSS on antenna performance.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127058531","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 : 2015-12-01DOI: 10.1109/IMARC.2015.7411371
O. Huber, Thomas Faseth, H. Arthaber, E. Schlaffer
As surface finishe play allegedly a crucial role in the overall performance of RF-circuits, this paper is dedicated to evaluate the impact of four different platings, as well as plain copper, on insertion loss for commercially manufactured RF-PCBs. The selected surface finishe are Electroless Nickel Immersion Gold (ENIG), Electroless Nickel Electroless Palladium Immersion Gold (ENEPIG), Immersion Tin, and a manufacturer specifi "shiny"-gold. Although each finis has different involved processing steps, materials, and price, basically no difference in insertion loss has been measured up to 110 GHz for microstrip (MS) or conductor backed coplanar waveguides (CBCPW). Additionally, the impact of manufacturing tolerances on insertion loss has been quantified These tolerances have shown more variation on insertion loss than for all investigated surface finishes with deviations of -11 % and 14 % in insertion loss at 100 GHz of the overall mean. For obtaining accurate data, appropriate launching pad designs have been evaluated previously for conducting reliable wafer prober measurements of wet etched RF-circuits up to 110 GHz.
{"title":"Optimized launching pads for investigating transmission line losses for different surface finishes of RF-PCBs up to 110 GHz","authors":"O. Huber, Thomas Faseth, H. Arthaber, E. Schlaffer","doi":"10.1109/IMARC.2015.7411371","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411371","url":null,"abstract":"As surface finishe play allegedly a crucial role in the overall performance of RF-circuits, this paper is dedicated to evaluate the impact of four different platings, as well as plain copper, on insertion loss for commercially manufactured RF-PCBs. The selected surface finishe are Electroless Nickel Immersion Gold (ENIG), Electroless Nickel Electroless Palladium Immersion Gold (ENEPIG), Immersion Tin, and a manufacturer specifi \"shiny\"-gold. Although each finis has different involved processing steps, materials, and price, basically no difference in insertion loss has been measured up to 110 GHz for microstrip (MS) or conductor backed coplanar waveguides (CBCPW). Additionally, the impact of manufacturing tolerances on insertion loss has been quantified These tolerances have shown more variation on insertion loss than for all investigated surface finishes with deviations of -11 % and 14 % in insertion loss at 100 GHz of the overall mean. For obtaining accurate data, appropriate launching pad designs have been evaluated previously for conducting reliable wafer prober measurements of wet etched RF-circuits up to 110 GHz.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130745767","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 : 2015-12-01DOI: 10.1109/IMARC.2015.7411379
Arani Ali Khan, M. Mandal, Ravi Shaw
In this paper, a novel excitation technique by a commercially available SMA connector is presented for the empty substrate integrated waveguide (ESIW). The SMA connector is directly connected to one end of the ESIW. A prototype back-to-back transition is designed and fabricated for X-band operation. Measurement results show that the insertion loss of the back-to-back transition is below 1 dB over 7.15 GHz to 12.5 GHz. Losses from the transition are studied in details. The transition has a compact dimension of 22 mm × 3.5 mm.
{"title":"A compact and wideband SMA connector to empty substrate integrated waveguide (ESIW) transition","authors":"Arani Ali Khan, M. Mandal, Ravi Shaw","doi":"10.1109/IMARC.2015.7411379","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411379","url":null,"abstract":"In this paper, a novel excitation technique by a commercially available SMA connector is presented for the empty substrate integrated waveguide (ESIW). The SMA connector is directly connected to one end of the ESIW. A prototype back-to-back transition is designed and fabricated for X-band operation. Measurement results show that the insertion loss of the back-to-back transition is below 1 dB over 7.15 GHz to 12.5 GHz. Losses from the transition are studied in details. The transition has a compact dimension of 22 mm × 3.5 mm.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134177112","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 : 2015-12-01DOI: 10.1109/IMARC.2015.7411417
Subin Joseph, P. Sreekumari Amma, K. A. Amal, Ajoy Kumar Mondal, R. Ratheesh
An Ultrawideband (UWB) MIMO antenna capable of covering 3.1 to 10.6 GHz frequency band having compact size is presented. To avoid severe electromagnetic interference from the narrow band services, band rejection characteristics is provided at 3.3 to 3.7 GHz WiMAX band and 5.15 to 5.85 GHz WLAN band. The proposed antenna gives good isolation of less than -20 dB at all frequencies. Results show that the H plane radiation pattern is omni-directional and antenna gain is almost stable in the entire operating frequency range. Envelope correlation coefficient less than 0.008 ensures better diversity performance.
{"title":"Compact UWB MIMO antenna with WiMAX and WLAN rejection","authors":"Subin Joseph, P. Sreekumari Amma, K. A. Amal, Ajoy Kumar Mondal, R. Ratheesh","doi":"10.1109/IMARC.2015.7411417","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411417","url":null,"abstract":"An Ultrawideband (UWB) MIMO antenna capable of covering 3.1 to 10.6 GHz frequency band having compact size is presented. To avoid severe electromagnetic interference from the narrow band services, band rejection characteristics is provided at 3.3 to 3.7 GHz WiMAX band and 5.15 to 5.85 GHz WLAN band. The proposed antenna gives good isolation of less than -20 dB at all frequencies. Results show that the H plane radiation pattern is omni-directional and antenna gain is almost stable in the entire operating frequency range. Envelope correlation coefficient less than 0.008 ensures better diversity performance.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114619524","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 : 2015-12-01DOI: 10.1109/IMARC.2015.7411388
Himanshu Samant, Abhishek Kumar Jha, M. J. Akhtar
A dual band coplanar resonator sensor for microwave characterization of common dispersive liquids is proposed. The proposed technique provides single step dielectric measurement of dispersive liquids at two designated microwave frequencies. For this purpose, two resonators etched on the central conductor of the coplanar waveguide are designed to resonate at industrial, scientific and medical (ISM) bands of frequency, 2.45 GHz and 5.85 GHz, respectively. For the accurate characterization of the material under test, a numerical model of the proposed sensor is developed which provides the real part of relative permittivity (εr) in terms of the resonant frequency corresponding to each resonator structure. The proposed sensor is fabricated on a 1.6 mm thick FR4 substrate, and its accuracy is experimentally verified by testing a number of standard liquids and comparing the measured data their values available in the literature.
{"title":"Design of coplanar dual band resonator sensor for microwave characterization of dispersive liquids","authors":"Himanshu Samant, Abhishek Kumar Jha, M. J. Akhtar","doi":"10.1109/IMARC.2015.7411388","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411388","url":null,"abstract":"A dual band coplanar resonator sensor for microwave characterization of common dispersive liquids is proposed. The proposed technique provides single step dielectric measurement of dispersive liquids at two designated microwave frequencies. For this purpose, two resonators etched on the central conductor of the coplanar waveguide are designed to resonate at industrial, scientific and medical (ISM) bands of frequency, 2.45 GHz and 5.85 GHz, respectively. For the accurate characterization of the material under test, a numerical model of the proposed sensor is developed which provides the real part of relative permittivity (εr) in terms of the resonant frequency corresponding to each resonator structure. The proposed sensor is fabricated on a 1.6 mm thick FR4 substrate, and its accuracy is experimentally verified by testing a number of standard liquids and comparing the measured data their values available in the literature.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115704153","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 : 2015-12-01DOI: 10.1109/IMARC.2015.7411375
A. Azad, A. Mohan, D. Jhariya
This paper presents an electric coupling structure with enhanced coupling coefficient based on double-layered SIW cavity resonators. Short-ended striplines are used to achieve electric coupling between two SIW cavities. The electric coupling depends on the width of the stripline. The proposed structure can achieve coupling coefficient more than 0.14. A fourth-order cross-coupled filter having centre frequency of 9.7 GHz and fractional bandwidth of 12% has been designed to verify the structure.
{"title":"Double-layered siw filter with enhanced electric coupling structure using three short-ended striplines","authors":"A. Azad, A. Mohan, D. Jhariya","doi":"10.1109/IMARC.2015.7411375","DOIUrl":"https://doi.org/10.1109/IMARC.2015.7411375","url":null,"abstract":"This paper presents an electric coupling structure with enhanced coupling coefficient based on double-layered SIW cavity resonators. Short-ended striplines are used to achieve electric coupling between two SIW cavities. The electric coupling depends on the width of the stripline. The proposed structure can achieve coupling coefficient more than 0.14. A fourth-order cross-coupled filter having centre frequency of 9.7 GHz and fractional bandwidth of 12% has been designed to verify the structure.","PeriodicalId":307742,"journal":{"name":"2015 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114239365","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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