Pub Date : 2013-04-14DOI: 10.1109/IEEE-IWS.2013.6616765
Juhua Liu, Q. Xue, Y. Long
A new kind of Yagi array of microstrip quarter-wave patch antennas is presented. The antenna array has a low profile and provides a high gain and a vertical polarization at endfire. Compared with previous Yagi array of microstrip half-wave patch antennas, the Yagi array of quarter-wave patch antennas has a smaller size and does not suffer the constraint in dielectric constant in the substrate. Besides, the presented Yagi array generates a main beam pointing closer to endfire than the Yagi array of half-wave patch antennas. Measured results show that the presented Yagi array with 4 elements would generate a peak gain of about 9.7 dBi, an endfire gain of about 4.5 dBi, and a bandwidth of 11.3% for a profile of 0.026 wavelengths. The front-to-back ratio of the Yagi array is higher than 10 dB.
{"title":"4-Element Yagi array of microstrip quarter-wave patch antennas","authors":"Juhua Liu, Q. Xue, Y. Long","doi":"10.1109/IEEE-IWS.2013.6616765","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2013.6616765","url":null,"abstract":"A new kind of Yagi array of microstrip quarter-wave patch antennas is presented. The antenna array has a low profile and provides a high gain and a vertical polarization at endfire. Compared with previous Yagi array of microstrip half-wave patch antennas, the Yagi array of quarter-wave patch antennas has a smaller size and does not suffer the constraint in dielectric constant in the substrate. Besides, the presented Yagi array generates a main beam pointing closer to endfire than the Yagi array of half-wave patch antennas. Measured results show that the presented Yagi array with 4 elements would generate a peak gain of about 9.7 dBi, an endfire gain of about 4.5 dBi, and a bandwidth of 11.3% for a profile of 0.026 wavelengths. The front-to-back ratio of the Yagi array is higher than 10 dB.","PeriodicalId":344851,"journal":{"name":"2013 IEEE International Wireless Symposium (IWS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128620164","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 : 2013-04-14DOI: 10.1109/IEEE-IWS.2013.6616849
Yue-Long Lv, F. Meng, Fang Zhang, Lei Zhu, J. Fu, Kuang Zhang, Qun Wu
A zero index metamaterial lens (ZIML) is proposed in this paper for antenna directivity and gain enhancement. The zero index metamaterial (ZIM) is constructed from both electric metamaterial with near-zero permittivity and magnetic metamaterial-modified split ring resonator (MSRR)-with near-zero permeability. The ZIM unit cell is numerically simulated in CST MWS. The scattering parameters show that there is a wide pass band where both permittivity and permeability are small enough to achieve wave collimation. Particularly, both of the two parameters are of the same value of 0.25, which not only obtains near-zero refractive index but also makes the relative characteristic impedance to be 1 and match that of air. A patch antenna and an H-plane horn antenna are also implemented to examine the directivity and gain enhancement ability of the ZIML. The E-plane radiation patterns are both sharpened greatly. The gain enhancement of patch antenna and H-plane horn antenna are 6.6 dB and 4.3 dB, respectively. The universality of the ZIML for both patch antenna and H-plane horn antenna indicates a more flexible application of the ZIML compared with traditional ones.
{"title":"A zero index metamaterial lens for gain enhancement of patch antenna and H-plane horn antenna","authors":"Yue-Long Lv, F. Meng, Fang Zhang, Lei Zhu, J. Fu, Kuang Zhang, Qun Wu","doi":"10.1109/IEEE-IWS.2013.6616849","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2013.6616849","url":null,"abstract":"A zero index metamaterial lens (ZIML) is proposed in this paper for antenna directivity and gain enhancement. The zero index metamaterial (ZIM) is constructed from both electric metamaterial with near-zero permittivity and magnetic metamaterial-modified split ring resonator (MSRR)-with near-zero permeability. The ZIM unit cell is numerically simulated in CST MWS. The scattering parameters show that there is a wide pass band where both permittivity and permeability are small enough to achieve wave collimation. Particularly, both of the two parameters are of the same value of 0.25, which not only obtains near-zero refractive index but also makes the relative characteristic impedance to be 1 and match that of air. A patch antenna and an H-plane horn antenna are also implemented to examine the directivity and gain enhancement ability of the ZIML. The E-plane radiation patterns are both sharpened greatly. The gain enhancement of patch antenna and H-plane horn antenna are 6.6 dB and 4.3 dB, respectively. The universality of the ZIML for both patch antenna and H-plane horn antenna indicates a more flexible application of the ZIML compared with traditional ones.","PeriodicalId":344851,"journal":{"name":"2013 IEEE International Wireless Symposium (IWS)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121357152","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 : 2013-04-14DOI: 10.1109/IEEE-IWS.2013.6616705
Zhengyu Sun, Hongwen Yang, Lijun Zhang, Yuepeng Yan
This paper demonstrates a fully single-ended broadband receiver front-end using a 0.5μm InGaAs E-mode pHEMT technology. The receiver consists of a wideband low-noise amplifier (LNA) and a wideband mixer with active baluns. A modified Kukielka LNA with the added LC-ladder matching network for bandwidth extension and noise optimization is employed. A new switched transconductor mixer embedded with an active balun for the local oscillator (LO) signal is designed. Measured results show that the front-end can achieve conversion gain of 26-29 dB, double sideband noise figure of 2.6-4.4 dB over the entire frequency range of 0.7 to 5.2 GHz. Based on the proposed front-end, an image-reject receiver is also presented with an image rejection of 35 dBc within the bandwidth.
{"title":"Low noise fully single-ended broadband receiver front-end with InGaAs pHEMT technology","authors":"Zhengyu Sun, Hongwen Yang, Lijun Zhang, Yuepeng Yan","doi":"10.1109/IEEE-IWS.2013.6616705","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2013.6616705","url":null,"abstract":"This paper demonstrates a fully single-ended broadband receiver front-end using a 0.5μm InGaAs E-mode pHEMT technology. The receiver consists of a wideband low-noise amplifier (LNA) and a wideband mixer with active baluns. A modified Kukielka LNA with the added LC-ladder matching network for bandwidth extension and noise optimization is employed. A new switched transconductor mixer embedded with an active balun for the local oscillator (LO) signal is designed. Measured results show that the front-end can achieve conversion gain of 26-29 dB, double sideband noise figure of 2.6-4.4 dB over the entire frequency range of 0.7 to 5.2 GHz. Based on the proposed front-end, an image-reject receiver is also presented with an image rejection of 35 dBc within the bandwidth.","PeriodicalId":344851,"journal":{"name":"2013 IEEE International Wireless Symposium (IWS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121413513","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 : 2013-04-14DOI: 10.1109/IEEE-IWS.2013.6616720
Jingshi Yao, Xiaopeng Sun, B. Lin
This paper presents a wideband, fully integrated, low-noise amplifier with a noise figure of less than 0.5 dB. The device is fabricated in a 0.35 μm GaAs enhancement-mode pHEMT process because of its positive threshold voltage and superior noise performance. The amplifier is housed in a low-cost 2×2 mm2 8-pin QFN plastic package with internal gate biasing and input and output matching. To our knowledge, this work achieved the best result of reported combination of low noise figure, OIP3 (40 dBm), and Linearity Figure of Merit (LFOM) of 15dB at a frequency range of 1.5-2.7GHz for sub-0.5 dB NF LNA, and integrated power-down function for system control.
{"title":"Ultra low-noise highly linear integrated 1.5 to 2.7 GHz LNA","authors":"Jingshi Yao, Xiaopeng Sun, B. Lin","doi":"10.1109/IEEE-IWS.2013.6616720","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2013.6616720","url":null,"abstract":"This paper presents a wideband, fully integrated, low-noise amplifier with a noise figure of less than 0.5 dB. The device is fabricated in a 0.35 μm GaAs enhancement-mode pHEMT process because of its positive threshold voltage and superior noise performance. The amplifier is housed in a low-cost 2×2 mm2 8-pin QFN plastic package with internal gate biasing and input and output matching. To our knowledge, this work achieved the best result of reported combination of low noise figure, OIP3 (40 dBm), and Linearity Figure of Merit (LFOM) of 15dB at a frequency range of 1.5-2.7GHz for sub-0.5 dB NF LNA, and integrated power-down function for system control.","PeriodicalId":344851,"journal":{"name":"2013 IEEE International Wireless Symposium (IWS)","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115989211","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 : 2013-04-14DOI: 10.1109/IEEE-IWS.2013.6616776
T. Kao, Jenshan Lin
Non-contact vital sign detection using 60-GHz radar offers various advantages such as higher sensitivity and smaller antennas compared to lower-frequency systems, however, the respiration amplitude comparable to wavelength causes strong non-linear phase modulation, and relatively small heartbeat amplitude results in detection difficulty. In this paper, theoretical analysis and simulation of 60-GHz detection are provided to address these issues. Both shallow and deep breathings are tested in the experiments, and the detection technique monitoring both the fundamental and second harmonic of respiration is proposed. The phenomena explained in the work can be applied to many millimeter-wave Doppler radar applications where target displacement is comparable to or larger than the wavelength to ensure robust detection.
{"title":"Vital sign detection using 60-GHz Doppler radar system","authors":"T. Kao, Jenshan Lin","doi":"10.1109/IEEE-IWS.2013.6616776","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2013.6616776","url":null,"abstract":"Non-contact vital sign detection using 60-GHz radar offers various advantages such as higher sensitivity and smaller antennas compared to lower-frequency systems, however, the respiration amplitude comparable to wavelength causes strong non-linear phase modulation, and relatively small heartbeat amplitude results in detection difficulty. In this paper, theoretical analysis and simulation of 60-GHz detection are provided to address these issues. Both shallow and deep breathings are tested in the experiments, and the detection technique monitoring both the fundamental and second harmonic of respiration is proposed. The phenomena explained in the work can be applied to many millimeter-wave Doppler radar applications where target displacement is comparable to or larger than the wavelength to ensure robust detection.","PeriodicalId":344851,"journal":{"name":"2013 IEEE International Wireless Symposium (IWS)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126780411","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 : 2013-04-14DOI: 10.1109/IEEE-IWS.2013.6616775
F. Hu, S. Lucyszyn
This paper reports recent developments in the `THz Torch' technology, for short-range wireless data transfer. The ultra-low cost `THz Torch' concept was recently introduced as an ultra-secure non-contacting technology in the physical layer. Previous results reported a 10 bits/s link over a single channel, across a distance of 1 cm. In this paper, some fundamental limitations of this technology are analyzed and potential methods are proposed to further increase the data rate and working distance of the communications link. The improved single-channel system demonstrates a bit rate of 380 bits/s over a 1 cm range, which presents a factor of 38 improvement.
{"title":"Improved ‘THz Torch’ technology for short-range wireless data transfer","authors":"F. Hu, S. Lucyszyn","doi":"10.1109/IEEE-IWS.2013.6616775","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2013.6616775","url":null,"abstract":"This paper reports recent developments in the `THz Torch' technology, for short-range wireless data transfer. The ultra-low cost `THz Torch' concept was recently introduced as an ultra-secure non-contacting technology in the physical layer. Previous results reported a 10 bits/s link over a single channel, across a distance of 1 cm. In this paper, some fundamental limitations of this technology are analyzed and potential methods are proposed to further increase the data rate and working distance of the communications link. The improved single-channel system demonstrates a bit rate of 380 bits/s over a 1 cm range, which presents a factor of 38 improvement.","PeriodicalId":344851,"journal":{"name":"2013 IEEE International Wireless Symposium (IWS)","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126234093","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 : 2013-04-14DOI: 10.1109/IEEE-IWS.2013.6616779
Tsu-Wei Lin, J. Kuo, Shyh-Jong Chung
A compact quadruple-mode ring resonator is proposed for synthesis of a quasi-elliptic bandpass filter. The resonator is composed of four half-wavelength rings connected to a single grounded via. For miniaturization, the ring areas are overlapped and the crossovers are implemented by short CPW sections in the ground plane. As a result, the resonator uses about 50% area of a conventional dual-mode ring resonator filter. Among the four rings, all coupling coefficients are of inductive type realized by shorted high-impedance and coupledline sections. Two zeros are created by capacitive source-load coupling, and the response is synthesized by the coupling matrix method. Agreement between simulation and measurement results of a realized circuit validates the approach.
{"title":"Miniaturized microstrip quadruple-mode ring resonator filter with quasi-elliptic passband","authors":"Tsu-Wei Lin, J. Kuo, Shyh-Jong Chung","doi":"10.1109/IEEE-IWS.2013.6616779","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2013.6616779","url":null,"abstract":"A compact quadruple-mode ring resonator is proposed for synthesis of a quasi-elliptic bandpass filter. The resonator is composed of four half-wavelength rings connected to a single grounded via. For miniaturization, the ring areas are overlapped and the crossovers are implemented by short CPW sections in the ground plane. As a result, the resonator uses about 50% area of a conventional dual-mode ring resonator filter. Among the four rings, all coupling coefficients are of inductive type realized by shorted high-impedance and coupledline sections. Two zeros are created by capacitive source-load coupling, and the response is synthesized by the coupling matrix method. Agreement between simulation and measurement results of a realized circuit validates the approach.","PeriodicalId":344851,"journal":{"name":"2013 IEEE International Wireless Symposium (IWS)","volume":"218 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131856858","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 : 2013-04-14DOI: 10.1109/IEEE-IWS.2013.6616750
F. Mehran, R. Maunder
In this paper, permutations constructed based on algebraic derivations which are of particular interests due to better error-rate performance as well as simpler and practical hardware implementations, have been used in designing high performance fully-systematic joint space-time turbo coding technology. This scheme enjoys the integration of twin-/triplet-antenna bit-level space-time (ST) codes with the binary turbo-like codes of unpunctured codecs. The conducted performance evaluations reveal that this scheme has superior flare performance and yields additional coding gains in waterfall region, compared with the row-column block interleaved systems.
{"title":"Wireless MIMO systems employing joint turbo-like STBC codes with bit-level algebraically-interleaved URSCs","authors":"F. Mehran, R. Maunder","doi":"10.1109/IEEE-IWS.2013.6616750","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2013.6616750","url":null,"abstract":"In this paper, permutations constructed based on algebraic derivations which are of particular interests due to better error-rate performance as well as simpler and practical hardware implementations, have been used in designing high performance fully-systematic joint space-time turbo coding technology. This scheme enjoys the integration of twin-/triplet-antenna bit-level space-time (ST) codes with the binary turbo-like codes of unpunctured codecs. The conducted performance evaluations reveal that this scheme has superior flare performance and yields additional coding gains in waterfall region, compared with the row-column block interleaved systems.","PeriodicalId":344851,"journal":{"name":"2013 IEEE International Wireless Symposium (IWS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129514247","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 : 2013-04-14DOI: 10.1109/IEEE-IWS.2013.6616746
F. Ghezzo, Zhiya Zhao, Ruopeng Liu
In this work we describe the fabrication method used for packaging a 15cm × 15cm × 3cm polymer based beam splitter, a metamaterial device designed for operating at 17GHz. An injection molding technique was used to allow a low viscosity resin, curing at room temperature, to package ten FR4 substrate layers with metamaterial patterns on them. The metamaterial elements present on each layer were designed and their distribution optimized in order to achieve the splitting in two parts of an electromagnetic wave impinging on the front face of the component. A low dielectric, low loss epoxy resin for casting and suitable for packaging was selected as the injection polymer. The design of the electromagnetic behavior of the component took into consideration the full integration of the metamaterial elements and substrates into the polymeric host material. The measurements performed to verify the performance of the as-fabricated device are finally discussed.
{"title":"Packaging method for metamaterial based microwave devices","authors":"F. Ghezzo, Zhiya Zhao, Ruopeng Liu","doi":"10.1109/IEEE-IWS.2013.6616746","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2013.6616746","url":null,"abstract":"In this work we describe the fabrication method used for packaging a 15cm × 15cm × 3cm polymer based beam splitter, a metamaterial device designed for operating at 17GHz. An injection molding technique was used to allow a low viscosity resin, curing at room temperature, to package ten FR4 substrate layers with metamaterial patterns on them. The metamaterial elements present on each layer were designed and their distribution optimized in order to achieve the splitting in two parts of an electromagnetic wave impinging on the front face of the component. A low dielectric, low loss epoxy resin for casting and suitable for packaging was selected as the injection polymer. The design of the electromagnetic behavior of the component took into consideration the full integration of the metamaterial elements and substrates into the polymeric host material. The measurements performed to verify the performance of the as-fabricated device are finally discussed.","PeriodicalId":344851,"journal":{"name":"2013 IEEE International Wireless Symposium (IWS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129295900","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 : 2013-04-14DOI: 10.1109/IEEE-IWS.2013.6616757
He Zhu, Q. Chu
An ultra-wideband (UWB) bandpass filter with a notch-band and wide upper stopband is presented in this paper. The UWB filter is realized using a ring resonator which is loaded with two sets of stubs, i.e. one is loaded in the center and two little stubs at the symmetrical side locations. The loaded stubs are used to create transmission zeros in upper stopband thus high modes are suppressed greatly. Moreover, two identical meandered resonators are inserted within the stub-loaded ring resonator, creating a notch-band around 5.8 GHz. Finally, two UWB filters with and without notch-band are simulated, fabricated, and measured results provide an experimental validation of predicted performance of the filter.
{"title":"Ultra-wideband (UWB) bandpass filter based on stub-loaded ring resonator","authors":"He Zhu, Q. Chu","doi":"10.1109/IEEE-IWS.2013.6616757","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2013.6616757","url":null,"abstract":"An ultra-wideband (UWB) bandpass filter with a notch-band and wide upper stopband is presented in this paper. The UWB filter is realized using a ring resonator which is loaded with two sets of stubs, i.e. one is loaded in the center and two little stubs at the symmetrical side locations. The loaded stubs are used to create transmission zeros in upper stopband thus high modes are suppressed greatly. Moreover, two identical meandered resonators are inserted within the stub-loaded ring resonator, creating a notch-band around 5.8 GHz. Finally, two UWB filters with and without notch-band are simulated, fabricated, and measured results provide an experimental validation of predicted performance of the filter.","PeriodicalId":344851,"journal":{"name":"2013 IEEE International Wireless Symposium (IWS)","volume":"633 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114000120","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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