Three types of miniaturized multi-band differential bandpass filters (BPFs) using microstrip multi-mode resonators are presented in this paper. The first one is a dual-band differential BPF using four-mode stepped-impedance square ring loaded resonators (SI-SRLRs) with a controllable frequency separation between its common-mode (CM) and differential-mode (DM). Next, by adding two additional open-circuited stubs to the square ring of the SI-SRLR, a new six-mode SI-SRLR is then obtained. By using two coupled six-mode resonators, a tri-band differential BPF is designed. Finally, to reduce the insertion loss due to the metal loss, high-temperature superconducting (HTS) technology is applied to develop a fourth-order HTS dual-band differential BPF using modified SRLRs. All these BPFs shown compact size and favorable performance.
{"title":"Compact Multi-Band Differential Bandpass Filters Using Microstrip Multi-mode Resonators","authors":"Baoping Ren, Zhewang Ma, Haiwen Liu, X. Guan, Pin Wen, M. Ohira","doi":"10.1109/IEEE-IWS.2019.8804107","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8804107","url":null,"abstract":"Three types of miniaturized multi-band differential bandpass filters (BPFs) using microstrip multi-mode resonators are presented in this paper. The first one is a dual-band differential BPF using four-mode stepped-impedance square ring loaded resonators (SI-SRLRs) with a controllable frequency separation between its common-mode (CM) and differential-mode (DM). Next, by adding two additional open-circuited stubs to the square ring of the SI-SRLR, a new six-mode SI-SRLR is then obtained. By using two coupled six-mode resonators, a tri-band differential BPF is designed. Finally, to reduce the insertion loss due to the metal loss, high-temperature superconducting (HTS) technology is applied to develop a fourth-order HTS dual-band differential BPF using modified SRLRs. All these BPFs shown compact size and favorable performance.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"126 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126282936","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 : 2019-05-19DOI: 10.1109/IEEE-IWS.2019.8803932
W. Lai, S. Jang, Li Ying Chen
This letter presents a wide locking range variablemodulus LC ILFD designed with a dual-resonance resonator and the designed circuit was manufactured in the TSMC 0.18 µm CMOS process. The CMOS circuit’s die area is 1.02×0.93mm2. The ILFD can be used as a wide locking range divide-by-2, -3, -4 and -5 circuit, and it is found that the harmonic mixer is used for the divide-by -5 ILFD while other modulus ILFDs use the linear mixer approach. Consequently, wide-locking range is obtained for variable division ratio.
{"title":"LC-Tank Injection-Locked Frequency Divider with Variable Modulus","authors":"W. Lai, S. Jang, Li Ying Chen","doi":"10.1109/IEEE-IWS.2019.8803932","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803932","url":null,"abstract":"This letter presents a wide locking range variablemodulus LC ILFD designed with a dual-resonance resonator and the designed circuit was manufactured in the TSMC 0.18 µm CMOS process. The CMOS circuit’s die area is 1.02×0.93mm2. The ILFD can be used as a wide locking range divide-by-2, -3, -4 and -5 circuit, and it is found that the harmonic mixer is used for the divide-by -5 ILFD while other modulus ILFDs use the linear mixer approach. Consequently, wide-locking range is obtained for variable division ratio.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"851 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130871493","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 : 2019-05-19DOI: 10.1109/IEEE-IWS.2019.8804035
Wenjuan Chen, Dan Zhu, Chenxu Xie, S. Pan
A microwave photonic image-reject mixer (IRM) achieving a recorded image rejection ratio (IRR) based on balanced Hartley architecture and an optical pre-filter is proposed and demonstrated. A theoretical model is established to study the influence of the power imbalance and the phase inaccuracy in the balanced Hartley architecture on the IRR. With the assistance of an optical pre-filter, a high IRR can be obtained with moderate amplitude and phase consistencies for the balanced Hartley architecture. A proof-of-concept experiment is carried out. The IRR larger than 90 dB is successfully realized for RF frequencies tuning from 10 to 40 GHz.
{"title":"Image reject mixer with greatly improved rejection ratio based on the balanced Hartley architecture","authors":"Wenjuan Chen, Dan Zhu, Chenxu Xie, S. Pan","doi":"10.1109/IEEE-IWS.2019.8804035","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8804035","url":null,"abstract":"A microwave photonic image-reject mixer (IRM) achieving a recorded image rejection ratio (IRR) based on balanced Hartley architecture and an optical pre-filter is proposed and demonstrated. A theoretical model is established to study the influence of the power imbalance and the phase inaccuracy in the balanced Hartley architecture on the IRR. With the assistance of an optical pre-filter, a high IRR can be obtained with moderate amplitude and phase consistencies for the balanced Hartley architecture. A proof-of-concept experiment is carried out. The IRR larger than 90 dB is successfully realized for RF frequencies tuning from 10 to 40 GHz.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125644557","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 : 2019-05-19DOI: 10.1109/IEEE-IWS.2019.8804029
Ying Sun, S. Xiao, Zhixin Yao, Qi Shi
A two-layer design which has a wideband transmission window within an ultra-wide absorption band, named as frequency-selective rasorber (FSR), is presented. This structure enables small insertion loss in the wide transmission window, with two absorption bands below and above the passband. The equivalent circuit (EC) is employed to make the design clearer and straightforward. Compared with other FSRs, it has a much wider transmission band with an ultra-wide absorption band and relative low profile. The simulated results exhibit that the insertion loss is less than 3 dB from 9.59 to 12.16 GHz (23.6%), while the frequency for –10dB reflection coefficient ranges from 5.4 to 17GHz (103.6%) with a thickness of 0.106λL (λL is wavelength at the lowest working frequency).
{"title":"A Wideband Frequency-Selective Rasorber Based on Interdigital Resonator and Fractal Shaped Slot","authors":"Ying Sun, S. Xiao, Zhixin Yao, Qi Shi","doi":"10.1109/IEEE-IWS.2019.8804029","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8804029","url":null,"abstract":"A two-layer design which has a wideband transmission window within an ultra-wide absorption band, named as frequency-selective rasorber (FSR), is presented. This structure enables small insertion loss in the wide transmission window, with two absorption bands below and above the passband. The equivalent circuit (EC) is employed to make the design clearer and straightforward. Compared with other FSRs, it has a much wider transmission band with an ultra-wide absorption band and relative low profile. The simulated results exhibit that the insertion loss is less than 3 dB from 9.59 to 12.16 GHz (23.6%), while the frequency for –10dB reflection coefficient ranges from 5.4 to 17GHz (103.6%) with a thickness of 0.106λL (λL is wavelength at the lowest working frequency).","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"248 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124410984","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 : 2019-05-19DOI: 10.1109/IEEE-IWS.2019.8803938
Md Khalid Hossain Jewel, Rabiu Sale Zakariyya, O. J. Famoriji, Md. Sadek Ali, F. Lin
3GPP introduced Narrow-Band Internet of Things (NB-IoT) in release-13 with a special feature to work with only 180 kHz bandwidth. Effective channel estimation is highly important for adequate receiver performance of NB-IoT system. Linear Minimum Mean Square Error (LMMSE) technique is very effective for estimating the channel condition but possesses high complexity. Singular value decomposition (SVD) and splitting the channel autocorrelation matrix into several submatrices reduces the complexity of LMMSE technique. In this paper, we propose a modified low complexity and computationally efficient LMMSE estimator by linking the advantages of both techniques stated above with overlap banded technique in channel autocorrelation matrix for NB-IoT downlink (in-band) system. In the proposed technique, subdivided channel autocorrelation matrices are overlapped among them and hence reduces complexity. Simulation results show that by dint of negligible degradation of performance, the complexity is significantly reduced.
{"title":"A Low Complexity Channel Estimation Technique for NB-IoT Downlink System","authors":"Md Khalid Hossain Jewel, Rabiu Sale Zakariyya, O. J. Famoriji, Md. Sadek Ali, F. Lin","doi":"10.1109/IEEE-IWS.2019.8803938","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803938","url":null,"abstract":"3GPP introduced Narrow-Band Internet of Things (NB-IoT) in release-13 with a special feature to work with only 180 kHz bandwidth. Effective channel estimation is highly important for adequate receiver performance of NB-IoT system. Linear Minimum Mean Square Error (LMMSE) technique is very effective for estimating the channel condition but possesses high complexity. Singular value decomposition (SVD) and splitting the channel autocorrelation matrix into several submatrices reduces the complexity of LMMSE technique. In this paper, we propose a modified low complexity and computationally efficient LMMSE estimator by linking the advantages of both techniques stated above with overlap banded technique in channel autocorrelation matrix for NB-IoT downlink (in-band) system. In the proposed technique, subdivided channel autocorrelation matrices are overlapped among them and hence reduces complexity. Simulation results show that by dint of negligible degradation of performance, the complexity is significantly reduced.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122265840","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 : 2019-05-19DOI: 10.1109/IEEE-IWS.2019.8803935
Haomin Hou, Jin He, Yao Peng, Tianchuan Deng, Zhiyuan Cao, Hao Wang, Sheng Chang, Qijun Huang
A four-stage wideband power amplifier (PA) using pole-tuning technique is presented for 5G applications. By tuning the relative pole position of each stage at different frequencies, the PA achieves a flat gain response over a wide bandwidth. To avoid transistor breakdown and hot carrier effect, self-biased cascode amplifiers are implemented in the first two stages. Common source amplifiers are utilized to ensure high output power. The PA was designed and simulated based on a 0.13 μm CMOS process. The post-simulation result exhibits a peak gain of 22.2 dB at 28 GHz with -3-dB bandwidth of 8 GHz. The saturated output power (Psat) and output 1 dB compression point (P1dB) are 11.6 dBm and 7.8 dBm, respectively. The peak power added efficiency (PAE) is 17.3%. The power consumption is 76 mW.
{"title":"A 22.5-30.5GHz CMOS Power Amplifier Using Pole-tuning Technique for 5G Applications","authors":"Haomin Hou, Jin He, Yao Peng, Tianchuan Deng, Zhiyuan Cao, Hao Wang, Sheng Chang, Qijun Huang","doi":"10.1109/IEEE-IWS.2019.8803935","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803935","url":null,"abstract":"A four-stage wideband power amplifier (PA) using pole-tuning technique is presented for 5G applications. By tuning the relative pole position of each stage at different frequencies, the PA achieves a flat gain response over a wide bandwidth. To avoid transistor breakdown and hot carrier effect, self-biased cascode amplifiers are implemented in the first two stages. Common source amplifiers are utilized to ensure high output power. The PA was designed and simulated based on a 0.13 μm CMOS process. The post-simulation result exhibits a peak gain of 22.2 dB at 28 GHz with -3-dB bandwidth of 8 GHz. The saturated output power (Psat) and output 1 dB compression point (P1dB) are 11.6 dBm and 7.8 dBm, respectively. The peak power added efficiency (PAE) is 17.3%. The power consumption is 76 mW.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129439703","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 : 2019-05-19DOI: 10.1109/IEEE-IWS.2019.8803964
Jinhua Chen, Peng Miao, Dixian Zhao
A Wilkinson power combiner performed in shielded coplanar waveguide is presented in this paper. A lumped circuit model has been proposed for the design and optimization of this work. Fabricated in 65-nm CMOS technology, the Wilkinson power combiner occupies a core chip area of 266 × 382 μm2. The measured insertion loss is 0.92-1.33 dB at 20-40 GHz. The input return loss is better than 15.5 dB and the output return loss is better than 25 dB from 20 to 40 GHz. The port-to-port isolation is better than 14.5 dB from 20 to 40 GHz.
{"title":"Analysis, Design and Modeling of Millimeter-Wave Wilkinson Power Combiner for 5G Phased Array","authors":"Jinhua Chen, Peng Miao, Dixian Zhao","doi":"10.1109/IEEE-IWS.2019.8803964","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8803964","url":null,"abstract":"A Wilkinson power combiner performed in shielded coplanar waveguide is presented in this paper. A lumped circuit model has been proposed for the design and optimization of this work. Fabricated in 65-nm CMOS technology, the Wilkinson power combiner occupies a core chip area of 266 × 382 μm2. The measured insertion loss is 0.92-1.33 dB at 20-40 GHz. The input return loss is better than 15.5 dB and the output return loss is better than 25 dB from 20 to 40 GHz. The port-to-port isolation is better than 14.5 dB from 20 to 40 GHz.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128379404","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 : 2019-05-19DOI: 10.1109/IEEE-IWS.2019.8804014
Dehan Wang, Wen-hua Chen, Long Chen, Zhenghe Feng
A broadband linear millimeter-wave power amplifier (PA) with an adaptive bias circuit implemented in 0.25 um SiGe BiCMOS for 5G millimeter-wave phased arrays is presented in this paper. The PA demonstrates a measured 21.7-dB small signal gain, 17.1-dBm saturated output power and 26.5% peak power added efficiency (PAE) at 27 GHz and the peak PAE maintains over 20% from 25 GHz to 32 GHz. At 27.5 GHz, the proposed PA is tested with an 800 MHz bandwidth 64-QAM signal without digital predistortion, which achieves a PAE of 11.56%, error vector magnitude (EVM) of −29.7 dB, and adjacent channel leakage ratio (ACLR) of −28.01 dBc at an average output power of 8.77 dBm.
{"title":"A Broadband Linear Millimeter-Wave Power Amplifier With an Adaptive Bias Circuit","authors":"Dehan Wang, Wen-hua Chen, Long Chen, Zhenghe Feng","doi":"10.1109/IEEE-IWS.2019.8804014","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8804014","url":null,"abstract":"A broadband linear millimeter-wave power amplifier (PA) with an adaptive bias circuit implemented in 0.25 um SiGe BiCMOS for 5G millimeter-wave phased arrays is presented in this paper. The PA demonstrates a measured 21.7-dB small signal gain, 17.1-dBm saturated output power and 26.5% peak power added efficiency (PAE) at 27 GHz and the peak PAE maintains over 20% from 25 GHz to 32 GHz. At 27.5 GHz, the proposed PA is tested with an 800 MHz bandwidth 64-QAM signal without digital predistortion, which achieves a PAE of 11.56%, error vector magnitude (EVM) of −29.7 dB, and adjacent channel leakage ratio (ACLR) of −28.01 dBc at an average output power of 8.77 dBm.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"302 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128624470","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}
Dual-band metasurface with high efficiency is highly desired for the electromagnetic integrated system. In this paper, a dual-band transmissive meta-atom is proposed to work at cross-polarized mode for the circularly polarized incidence. The meta-atom could achieve a 360° phase coverage with conversion efficiencies better than 70% at two frequencies of X-band simultaneously. As a proof of concept demonstration, a dual-band deflector based on metasurface is designed to deflect the incident wave to the anomalous directions with arbitrary deflection angles. The simulated results show a good expected performance, which could pave the way towards high-efficiency integrated components.
{"title":"A High-efficiency Dual-band Deflector Based on Geometric Metasurface in the X-Band","authors":"Rensheng Xie, Mingbo Xin, Yiting Liu, Tailei Wang, Guohua Zhai, Jianjun Gao, Jun Ding","doi":"10.1109/IEEE-IWS.2019.8804002","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8804002","url":null,"abstract":"Dual-band metasurface with high efficiency is highly desired for the electromagnetic integrated system. In this paper, a dual-band transmissive meta-atom is proposed to work at cross-polarized mode for the circularly polarized incidence. The meta-atom could achieve a 360° phase coverage with conversion efficiencies better than 70% at two frequencies of X-band simultaneously. As a proof of concept demonstration, a dual-band deflector based on metasurface is designed to deflect the incident wave to the anomalous directions with arbitrary deflection angles. The simulated results show a good expected performance, which could pave the way towards high-efficiency integrated components.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"2008 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131414767","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 : 2019-05-19DOI: 10.1109/IEEE-IWS.2019.8804069
Ren-Jie Gong, Y. Ban, S. Yan, Jiang-Wei Zheng
A circularly polarized array consisting of magneto-electric (ME) dipole antennas with beam scanning is proposed, which is fed by a substrate integrated waveguide (SIW) 3 × 3 butler matrix. The wide AR beamwidth antenna element is the key to completing the antenna array. In order to ensure the generation of normal beam, the 3 × 3 butler matrix was adopted as the beam-forming network. The proposed structure operates in the range of 27.5GHz ~ 28.5GHz and generates three circularly polarized beams that cover the range of ±40°.
{"title":"Three-Beam Circularly Polarized ME Dipole Antenna Array Fed by 3 × 3 Butler Matrix","authors":"Ren-Jie Gong, Y. Ban, S. Yan, Jiang-Wei Zheng","doi":"10.1109/IEEE-IWS.2019.8804069","DOIUrl":"https://doi.org/10.1109/IEEE-IWS.2019.8804069","url":null,"abstract":"A circularly polarized array consisting of magneto-electric (ME) dipole antennas with beam scanning is proposed, which is fed by a substrate integrated waveguide (SIW) 3 × 3 butler matrix. The wide AR beamwidth antenna element is the key to completing the antenna array. In order to ensure the generation of normal beam, the 3 × 3 butler matrix was adopted as the beam-forming network. The proposed structure operates in the range of 27.5GHz ~ 28.5GHz and generates three circularly polarized beams that cover the range of ±40°.","PeriodicalId":306297,"journal":{"name":"2019 IEEE MTT-S International Wireless Symposium (IWS)","volume":"166 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122979948","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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