Pub Date : 2022-08-12DOI: 10.1109/IWS55252.2022.9977671
Lu‐Chuan Zhang, Guangnian Wang, H. Tao, Runnan Guo, Yuan Zhuang, Yan Chen, Min Lv, Longxing Shi
A high-power, high-efficiency, 6-18GHz monolithic microwave integrated circuit (MMIC) power amplifier (PA) utilizing active load modulation is devised and evaluated in this document. The ultra-wideband (UWB) MMIC PA, manufactured in $boldsymbol{0.20-mu} mathbf{m}$ gallium nitride (GaN) process, is intended not only with standard passive matching but also with an active methodology to identify the most appropriate impedances. The PA assessment findings indicated a power added efficiency (PAE) of 25% to 38% over 6–18 GHz with an average power gain of 21 dB and an output power greater than 44 dBm (25 W) at a drain voltage of 28V at 1ms pulse width with 10% duty cycle. The chip dimension is 4.7mm × 5.5 mm (25.85 mm2).
{"title":"A 6-18GHz 25W High-Efficiency GaN Power Amplifier MMIC Using Active Load Modulation","authors":"Lu‐Chuan Zhang, Guangnian Wang, H. Tao, Runnan Guo, Yuan Zhuang, Yan Chen, Min Lv, Longxing Shi","doi":"10.1109/IWS55252.2022.9977671","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977671","url":null,"abstract":"A high-power, high-efficiency, 6-18GHz monolithic microwave integrated circuit (MMIC) power amplifier (PA) utilizing active load modulation is devised and evaluated in this document. The ultra-wideband (UWB) MMIC PA, manufactured in $boldsymbol{0.20-mu} mathbf{m}$ gallium nitride (GaN) process, is intended not only with standard passive matching but also with an active methodology to identify the most appropriate impedances. The PA assessment findings indicated a power added efficiency (PAE) of 25% to 38% over 6–18 GHz with an average power gain of 21 dB and an output power greater than 44 dBm (25 W) at a drain voltage of 28V at 1ms pulse width with 10% duty cycle. The chip dimension is 4.7mm × 5.5 mm (25.85 mm2).","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134212771","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 : 2022-08-12DOI: 10.1109/IWS55252.2022.9977532
Siyi Li, Jiazhe Li, Heng Dong, Zhuoming Li
In order to meet people's demand for communication rate, massive MIMO technology has been introduced into 5G field, which has become a research hotspot due to its advantages of improving system capacity, ensuring communication quality and reducing communication cost. The acquisition of channel state information (CSI) is the basis of massive MIMO, however, the accuracy of existing channel estimation techniques is difficult to reach a satisfactory standard, especially when the number of antennas is small. In order to correct the shortcomings, this paper introduces the idea of least square signal detection on the basis of the traditional singular value decomposition (SVD) channel estimation algorithm. The joint algorithm uses SVD algorithm to calculate the channel matrix as the initial value of the signal detection, and then re-estimate the channel state by using the detected signal and the transmitted pilot. The theory and simulation show that the proposed estimation algorithm can effectively improve the accuracy of the estimation results compared with the traditional channel estimation algorithm.
{"title":"A Massive MIMO Channel Estimation Algorithm Design Combined the SVD Method with LS Signal Detection","authors":"Siyi Li, Jiazhe Li, Heng Dong, Zhuoming Li","doi":"10.1109/IWS55252.2022.9977532","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977532","url":null,"abstract":"In order to meet people's demand for communication rate, massive MIMO technology has been introduced into 5G field, which has become a research hotspot due to its advantages of improving system capacity, ensuring communication quality and reducing communication cost. The acquisition of channel state information (CSI) is the basis of massive MIMO, however, the accuracy of existing channel estimation techniques is difficult to reach a satisfactory standard, especially when the number of antennas is small. In order to correct the shortcomings, this paper introduces the idea of least square signal detection on the basis of the traditional singular value decomposition (SVD) channel estimation algorithm. The joint algorithm uses SVD algorithm to calculate the channel matrix as the initial value of the signal detection, and then re-estimate the channel state by using the detected signal and the transmitted pilot. The theory and simulation show that the proposed estimation algorithm can effectively improve the accuracy of the estimation results compared with the traditional channel estimation algorithm.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133991513","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}
Ships are often suffered from uncertain strong electromagnetic environment radiation during navigation, which always cause certain damage to their electrical equipment through coupling. In order to study the correlation characteristics between strong electromagnetic environment and damage characteristics, for the problems of information complexity and uncertainty in them. In this paper, the correlation analysis about complexity of their damage characteristics based on grey correlation is proposed. Combined with the physical characteristics of strong electromagnetic environment parameters, the correlation model of the corresponding coefficients is established, which shows that the model can find the main influencing factors from incomplete information. Thus, it can provide a effective solution for the strong electromagnetic protection process, improve the protection efficiency, verify the feasibility of this method through the measured data, and provide a better solution for the electromagnetic protection process in the future.
{"title":"Grey correlation analysis of strong electromagnetic environment and damage characteristics","authors":"Xuan-Chuan Cao, Bingchen Ge, Mengxue Li, Hai‐Ping Wang, Jiuchun Ren","doi":"10.1109/IWS55252.2022.9977497","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977497","url":null,"abstract":"Ships are often suffered from uncertain strong electromagnetic environment radiation during navigation, which always cause certain damage to their electrical equipment through coupling. In order to study the correlation characteristics between strong electromagnetic environment and damage characteristics, for the problems of information complexity and uncertainty in them. In this paper, the correlation analysis about complexity of their damage characteristics based on grey correlation is proposed. Combined with the physical characteristics of strong electromagnetic environment parameters, the correlation model of the corresponding coefficients is established, which shows that the model can find the main influencing factors from incomplete information. Thus, it can provide a effective solution for the strong electromagnetic protection process, improve the protection efficiency, verify the feasibility of this method through the measured data, and provide a better solution for the electromagnetic protection process in the future.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131625324","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 : 2022-08-12DOI: 10.1109/IWS55252.2022.9977884
Ming-Hsi Wu, Bing Zhang
In this paper, a double-folded Butler matrix multi-beam antenna based on SIW structure is proposed. The new $7times 8$ BM combines two intermediate input ports of the traditional $8times 8$ Butler matrix into one port, which provides output signals in the same phase so that the antenna can generate a beam of line-of-sight light. BM is folded twice to form three layers to make the BM size more compact. The measured results show that the maximum gain of this antenna is 17.3dBi within 29.5~30.5 GHz. The antenna is capable of generating 7 beams, including a boresight beam, which can scan in the range of -58°to 58°. It has obvious practical value in 5G.
{"title":"A Double Fold Multibeam Antenna for 5G Applications","authors":"Ming-Hsi Wu, Bing Zhang","doi":"10.1109/IWS55252.2022.9977884","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977884","url":null,"abstract":"In this paper, a double-folded Butler matrix multi-beam antenna based on SIW structure is proposed. The new $7times 8$ BM combines two intermediate input ports of the traditional $8times 8$ Butler matrix into one port, which provides output signals in the same phase so that the antenna can generate a beam of line-of-sight light. BM is folded twice to form three layers to make the BM size more compact. The measured results show that the maximum gain of this antenna is 17.3dBi within 29.5~30.5 GHz. The antenna is capable of generating 7 beams, including a boresight beam, which can scan in the range of -58°to 58°. It has obvious practical value in 5G.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129399130","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 : 2022-08-12DOI: 10.1109/IWS55252.2022.9978091
Hao Liu, Yuandan Dong
A double-layer wideband transmitarray antenna with small compensation elements is proposed. The double-layer transmitarray antenna consists of 441 standard elements and 128 small elements. Standard elements have two freedom degrees, which can achieve a 360° phase shift range. And small elements placed at the intersection of the four standard elements is able to generate an approximate 90° phase shift range. The simulation results show that the phase shift curve of the small unit is very flat with wide bandwidth. Therefore, the addition of small elements can not only increase the gain but also increase the bandwidth. The array is designed, manufactured and testing. The experimental data is in good agreement with the simulation. The proposed transmitarray achieves a gain of 29.5 dB at 34 GHz, with an aperture efficiency of 41% and 1dB gain bandwidth of 10.3% (32.1GHz-35.6GHz). The small elements can also be added to other similar lens antenna to enhance the gain and bandwidth.
{"title":"A Double-Layer Wideband Transmitarray Antenna with Compensation Elements","authors":"Hao Liu, Yuandan Dong","doi":"10.1109/IWS55252.2022.9978091","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9978091","url":null,"abstract":"A double-layer wideband transmitarray antenna with small compensation elements is proposed. The double-layer transmitarray antenna consists of 441 standard elements and 128 small elements. Standard elements have two freedom degrees, which can achieve a 360° phase shift range. And small elements placed at the intersection of the four standard elements is able to generate an approximate 90° phase shift range. The simulation results show that the phase shift curve of the small unit is very flat with wide bandwidth. Therefore, the addition of small elements can not only increase the gain but also increase the bandwidth. The array is designed, manufactured and testing. The experimental data is in good agreement with the simulation. The proposed transmitarray achieves a gain of 29.5 dB at 34 GHz, with an aperture efficiency of 41% and 1dB gain bandwidth of 10.3% (32.1GHz-35.6GHz). The small elements can also be added to other similar lens antenna to enhance the gain and bandwidth.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133748110","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 : 2022-08-12DOI: 10.1109/IWS55252.2022.9977959
Yuji Liu, Wanchen Yang, W. Che, Q. Xue, Wenhai Zhang
In this work, a millimeter-wave wide-angle scanning phased array is proposed. The antenna consists of two rectangular metasurface cells and it is fed by a L probe, which can obtain a large impedance bandwidth and a wide beam in E-plane. Then, the 1×2 subarray is designed to construct a 8×2 wide-angle scanning phased array with the array spacing of 0.38 λ0. A grounded “II” structure is loaded between the antenna elements to improve the active S-parameters when the phased array is scanning. As results, the 10-dB impedance bandwidth of the proposed array can cover a wide band of 66-78GHz (16.7%). Moreover, it can scans up to ±65° in the whole operating band-width, while gain drop is less than 3 dB, and the maximum scan range reaches ±69°.
{"title":"Millimeter Wave Wide-angle Scanning Phased Array Antenna","authors":"Yuji Liu, Wanchen Yang, W. Che, Q. Xue, Wenhai Zhang","doi":"10.1109/IWS55252.2022.9977959","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977959","url":null,"abstract":"In this work, a millimeter-wave wide-angle scanning phased array is proposed. The antenna consists of two rectangular metasurface cells and it is fed by a L probe, which can obtain a large impedance bandwidth and a wide beam in E-plane. Then, the 1×2 subarray is designed to construct a 8×2 wide-angle scanning phased array with the array spacing of 0.38 λ0. A grounded “II” structure is loaded between the antenna elements to improve the active S-parameters when the phased array is scanning. As results, the 10-dB impedance bandwidth of the proposed array can cover a wide band of 66-78GHz (16.7%). Moreover, it can scans up to ±65° in the whole operating band-width, while gain drop is less than 3 dB, and the maximum scan range reaches ±69°.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115529640","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}
An ultra-wide band tile-type Transmit/Receive module (T/R module) with the characteristics of high integration, small volume, light-weight is presented in this paper. The proposed T/R module can realize transmit/receive signal amplification, amplitude and phase control. In electrical design, two 2-channels multi-function MMICs (MFC) are applied to provide the amplitude and phase control of RF signal. And it is remarkable that large, the MFC is a three-dimensional (3D) chip which achieved by stacking digital circuits on top of the microwave circuits to increase densities. And 4 RF front modules are applied to realize transmit/receive signal amplification. The designed T/R module provides above 30dB of receive gain with Noise Figure (NF) better than 2.5dB, and up to 40dBm of pulsed power with about 35% of power added efficiency (PAE). In mechanical design, a newly assembly method of 3D vertical interconnection technology in the highly integrated packaging TR module is proposed. Signals transmission between the proposed TR module and the external system are achieved by fuzz-button connectors to form a vertical interconnection structure. The designed 4-channels T/R module is about 38mm38mm*8mm, and the total weight is 30g.
{"title":"Design and Implementation of an S/C Band Tile-Type TR Module","authors":"Xi Fu, Wenzhou Ruan, Qing Guo, Chao Qing, Wei Meng, Qifeng Yin","doi":"10.1109/IWS55252.2022.9977922","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977922","url":null,"abstract":"An ultra-wide band tile-type Transmit/Receive module (T/R module) with the characteristics of high integration, small volume, light-weight is presented in this paper. The proposed T/R module can realize transmit/receive signal amplification, amplitude and phase control. In electrical design, two 2-channels multi-function MMICs (MFC) are applied to provide the amplitude and phase control of RF signal. And it is remarkable that large, the MFC is a three-dimensional (3D) chip which achieved by stacking digital circuits on top of the microwave circuits to increase densities. And 4 RF front modules are applied to realize transmit/receive signal amplification. The designed T/R module provides above 30dB of receive gain with Noise Figure (NF) better than 2.5dB, and up to 40dBm of pulsed power with about 35% of power added efficiency (PAE). In mechanical design, a newly assembly method of 3D vertical interconnection technology in the highly integrated packaging TR module is proposed. Signals transmission between the proposed TR module and the external system are achieved by fuzz-button connectors to form a vertical interconnection structure. The designed 4-channels T/R module is about 38mm38mm*8mm, and the total weight is 30g.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115794312","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 : 2022-08-12DOI: 10.1109/IWS55252.2022.9977651
Yaxi Pan, Jian Dong
In this paper, a design method of frequency selective surface (FSS) using an equivalent circuit (EC) and multi-objective particle swarm optimization (MOPSO) algorithm is proposed in this paper. The EC with the desired frequency response is established first. Then the initial structure is determined based on the EC and building blocks. Finally, the structure parameters are optimized using the MOPSO algorithm. It was applied to the triple pass-band FSS, and the analysis of the results shows that such the global scan method can obtain the target FSS more swiftly and accurately.
{"title":"Design of FSS Using Equivalent Circuit and MOPSO algorithm","authors":"Yaxi Pan, Jian Dong","doi":"10.1109/IWS55252.2022.9977651","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977651","url":null,"abstract":"In this paper, a design method of frequency selective surface (FSS) using an equivalent circuit (EC) and multi-objective particle swarm optimization (MOPSO) algorithm is proposed in this paper. The EC with the desired frequency response is established first. Then the initial structure is determined based on the EC and building blocks. Finally, the structure parameters are optimized using the MOPSO algorithm. It was applied to the triple pass-band FSS, and the analysis of the results shows that such the global scan method can obtain the target FSS more swiftly and accurately.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129769906","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 : 2022-08-12DOI: 10.1109/IWS55252.2022.9977829
Kaixue Ma, Ting Feng, Lei Zhang
This paper gives a brief introduction of the proposed metal-integrated and substrate integrated suspended line (MI-SISL) technology, which is demonstrated as an attractive plat-form for high power and high-efficiency power amplifier integration with superiorities of high-performance and self-packaging and two MI-SISL based high power and high-efficiency power amplifiers (PAs) for 5G applications are introduced as the demonstration cases.
{"title":"MI-SISL Based 5G High-Efficiency Power Amplifier (invited)","authors":"Kaixue Ma, Ting Feng, Lei Zhang","doi":"10.1109/IWS55252.2022.9977829","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977829","url":null,"abstract":"This paper gives a brief introduction of the proposed metal-integrated and substrate integrated suspended line (MI-SISL) technology, which is demonstrated as an attractive plat-form for high power and high-efficiency power amplifier integration with superiorities of high-performance and self-packaging and two MI-SISL based high power and high-efficiency power amplifiers (PAs) for 5G applications are introduced as the demonstration cases.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":"1961 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129361761","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 : 2022-08-12DOI: 10.1109/IWS55252.2022.9978119
Yuchen Wang, T. Yuan, Guoguo Liu, Jiuding Zhou, Wenliang Liu, Yang Lu, Xiao-hua Ma, Yue Hao
In this paper, a DC to 40 GHz distributed amplifier (DA) employing the negative group delay technique has been successfully implemented using 0.15μm GaAs pHEMT process. It is shown that stagger-tuning negative group delay circuits can be realized in each gain cell of DA. This paper presents a significant improvement in low group delay variation compared to conventional DAs. The proposed DA provides a 15 dB average gain, 3 dB noise figure, and 8ps group delay variation which was validated through theoretical analysis and experimental results.
{"title":"A Broadband Amplifier with Low Group Delay Variation Implemented","authors":"Yuchen Wang, T. Yuan, Guoguo Liu, Jiuding Zhou, Wenliang Liu, Yang Lu, Xiao-hua Ma, Yue Hao","doi":"10.1109/IWS55252.2022.9978119","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9978119","url":null,"abstract":"In this paper, a DC to 40 GHz distributed amplifier (DA) employing the negative group delay technique has been successfully implemented using 0.15μm GaAs pHEMT process. It is shown that stagger-tuning negative group delay circuits can be realized in each gain cell of DA. This paper presents a significant improvement in low group delay variation compared to conventional DAs. The proposed DA provides a 15 dB average gain, 3 dB noise figure, and 8ps group delay variation which was validated through theoretical analysis and experimental results.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130060272","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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