Pub Date : 2022-08-12DOI: 10.1109/IWS55252.2022.9978120
Outong Gao, Lanlan Jiang, Haoshen Zhu, W. Che, Q. Xue
This paper reports the design of a broadband GaN low noise amplifier (LNA) microwave monolithic integrated circuit (MMIC). A novel transformer structure is proposed to implement the gm-boosting as well as bandwidth extension in the LNA. The designed LNA shows >20dB gain, <2dB noise figure (NF) and >14.5dBm output 1dB compression point (OP1dB) within a wide working frequency range from 20 to 41GHz, which fully covers the Ka-band. In addition, the gain and NF fluctuation is less than 2dB and 0.7dB, respectively. The die size of the LNA MMIC is 1.6×1mm2. This work verifies the feasibility of the transformer-based LNA design in GaN MMIC platform.
{"title":"A Transformed-based Ka-band GaN Low-Noise Amplifier MMIC","authors":"Outong Gao, Lanlan Jiang, Haoshen Zhu, W. Che, Q. Xue","doi":"10.1109/IWS55252.2022.9978120","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9978120","url":null,"abstract":"This paper reports the design of a broadband GaN low noise amplifier (LNA) microwave monolithic integrated circuit (MMIC). A novel transformer structure is proposed to implement the gm-boosting as well as bandwidth extension in the LNA. The designed LNA shows >20dB gain, <2dB noise figure (NF) and >14.5dBm output 1dB compression point (OP1dB) within a wide working frequency range from 20 to 41GHz, which fully covers the Ka-band. In addition, the gain and NF fluctuation is less than 2dB and 0.7dB, respectively. The die size of the LNA MMIC is 1.6×1mm2. This work verifies the feasibility of the transformer-based LNA design in GaN MMIC platform.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115632460","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/IWS55252.2022.9977801
Zihui Chi, Man Lu, Juan Li, Dan Wu, Huabei Jiang
Psoriatic arthritis is also known as arthropathic psoriasis, and can ultimately lead to j oint destruction and functional disabilities. Current clinical imaging techniques to assess psoriatic arthritis have their own advantages and disadvantages. The demand for sensitive and efficient tools for the diagnosis of psoriatic arthritis is on the rise. Here, as a novel imaging modality, thermoacoustic tomography was used to evaluate psoriatic arthritis. The preliminary result indicated that TAT images of the psoriatic arthritis joint showed differences in tissue structures and image contrast compared to the healthy ones. Therefore, the pilot study provides a foundation for TAT futher clinical validation to the diagnosis of psoriatic arthritis.
{"title":"Detection of psoriatic arthritis in the finger joints by Thermoacoustic Tomography","authors":"Zihui Chi, Man Lu, Juan Li, Dan Wu, Huabei Jiang","doi":"10.1109/IWS55252.2022.9977801","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977801","url":null,"abstract":"Psoriatic arthritis is also known as arthropathic psoriasis, and can ultimately lead to j oint destruction and functional disabilities. Current clinical imaging techniques to assess psoriatic arthritis have their own advantages and disadvantages. The demand for sensitive and efficient tools for the diagnosis of psoriatic arthritis is on the rise. Here, as a novel imaging modality, thermoacoustic tomography was used to evaluate psoriatic arthritis. The preliminary result indicated that TAT images of the psoriatic arthritis joint showed differences in tissue structures and image contrast compared to the healthy ones. Therefore, the pilot study provides a foundation for TAT futher clinical validation to the diagnosis of psoriatic arthritis.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123248748","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/IWS55252.2022.9978049
Xiaobin Lin, Da Li, Hongtao Lin, Erping Li
This article introduces the inverse design into the all-optical logic gates. Using direct-binary search (DBS) and the adjoint method, the ultra-small XOR logic gate is designed, and the size is only 1.2um*2.5um, which is the smallest record known so far. The device with parallel logic function in C-band and O-band is realized for the first time. All designs conform to standard processes, laying the foundation for the development of optical computing and optical neural networks.
{"title":"Ultra-small All-Optical Logic Gate Design based on Inverse Design for Wire-less Communication","authors":"Xiaobin Lin, Da Li, Hongtao Lin, Erping Li","doi":"10.1109/IWS55252.2022.9978049","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9978049","url":null,"abstract":"This article introduces the inverse design into the all-optical logic gates. Using direct-binary search (DBS) and the adjoint method, the ultra-small XOR logic gate is designed, and the size is only 1.2um*2.5um, which is the smallest record known so far. The device with parallel logic function in C-band and O-band is realized for the first time. All designs conform to standard processes, laying the foundation for the development of optical computing and optical neural networks.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115107857","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/IWS55252.2022.9977745
Wutao Chen, Kanglian Zhao, Wenfeng Li
In this paper, an improved method for simulating cloud liquid water content in a space-earth laser communication scenario is presented. Cloud liquid water can block high frequency laser link, so it is necessary to consider the change of cloud liquid water in satellite-ground laser communication scenarios to determine the laser link blocking situation. The original Integrated Liquid Water Content (ILWC) synthesizer adopts the input method of using statistical data of cloud liquid water in a single point, which is not exactly accurate but applicable to the scene with fixed satellite receiving point. The improved linear interpolation method for cloud liquid water statistical data input improves the overall accuracy of the input data. The simulation results are more accurate when the ground satellite receiving point is mobile, and can be used for a better resource scheduling of a multi-ground station satellite communication network.
{"title":"An optimized input system for long-term prediction of cloud liquid water content","authors":"Wutao Chen, Kanglian Zhao, Wenfeng Li","doi":"10.1109/IWS55252.2022.9977745","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977745","url":null,"abstract":"In this paper, an improved method for simulating cloud liquid water content in a space-earth laser communication scenario is presented. Cloud liquid water can block high frequency laser link, so it is necessary to consider the change of cloud liquid water in satellite-ground laser communication scenarios to determine the laser link blocking situation. The original Integrated Liquid Water Content (ILWC) synthesizer adopts the input method of using statistical data of cloud liquid water in a single point, which is not exactly accurate but applicable to the scene with fixed satellite receiving point. The improved linear interpolation method for cloud liquid water statistical data input improves the overall accuracy of the input data. The simulation results are more accurate when the ground satellite receiving point is mobile, and can be used for a better resource scheduling of a multi-ground station satellite communication network.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116113257","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/IWS55252.2022.9977624
Cong Tao, Liangbo Lei, Z. Chen, Zhiliang Hong, Yumei Huang
Wideband low noise transconductance amplifier(LNTA) is an essential part of current-mode SAW-less receivers, and its linearity design is the most challenging. Many low noise amplifier(LNA) linearization techniques(LT) are also applicable to LNTA, such as the famous derivative superposition(DS) and post-distortion(PD). But these techniques are not robust and are prone to failure. This paper is based on a noise canceling(NC) LNTA prototype and improves its performance in several aspects with some unique analysis. The robustness of the IIP3 of the original LNTA is enhanced by using a self-biasing network. By changing the connection of the DS MOSFETs, the sensitivity of the IIP3 to the load resistance is reduced. Finally, by adopting PD as a fine-tuning technique in the right place, the IIP3 of the LNTA is improved to more than 20dBm.
{"title":"Robustness Enhancement Technique and Fine-Tuning Technique of IIP3 for Wideband LNTA","authors":"Cong Tao, Liangbo Lei, Z. Chen, Zhiliang Hong, Yumei Huang","doi":"10.1109/IWS55252.2022.9977624","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977624","url":null,"abstract":"Wideband low noise transconductance amplifier(LNTA) is an essential part of current-mode SAW-less receivers, and its linearity design is the most challenging. Many low noise amplifier(LNA) linearization techniques(LT) are also applicable to LNTA, such as the famous derivative superposition(DS) and post-distortion(PD). But these techniques are not robust and are prone to failure. This paper is based on a noise canceling(NC) LNTA prototype and improves its performance in several aspects with some unique analysis. The robustness of the IIP3 of the original LNTA is enhanced by using a self-biasing network. By changing the connection of the DS MOSFETs, the sensitivity of the IIP3 to the load resistance is reduced. Finally, by adopting PD as a fine-tuning technique in the right place, the IIP3 of the LNTA is improved to more than 20dBm.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122804800","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/IWS55252.2022.9977627
Bowen Xia, Wen-hua Chen, Long Chen, Zhenghe Feng
In this paper, a 20–28 GHz four-stack millimeter-wave power amplifier (PA) is presented. The proposed P A adopted four-stack technology to raise the supply voltage to 3.3 V, which greatly increased the output power to 22.2dBm at 22GHz without complex power combining techniques and avoiding efficient loss introduced by combining network and DC-DC converter. Thanks to the transformer-based wideband matching network, the proposed PA provides more than 11.8 dB gain and 19.1dBm maximum power between 20–28 GHz. The proposed P A also has a compact size occupying only $900mu mathrm{m} {}^{*}500mu mathrm{m}$ in 22nm FDSOI technology including all pads and seal ring.
{"title":"A 20–28 GHz Four-Stack Millimeter-Wave Power Amplifier with 22.2-dBm Psat in 22-nm FDSOI Technology","authors":"Bowen Xia, Wen-hua Chen, Long Chen, Zhenghe Feng","doi":"10.1109/IWS55252.2022.9977627","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977627","url":null,"abstract":"In this paper, a 20–28 GHz four-stack millimeter-wave power amplifier (PA) is presented. The proposed P A adopted four-stack technology to raise the supply voltage to 3.3 V, which greatly increased the output power to 22.2dBm at 22GHz without complex power combining techniques and avoiding efficient loss introduced by combining network and DC-DC converter. Thanks to the transformer-based wideband matching network, the proposed PA provides more than 11.8 dB gain and 19.1dBm maximum power between 20–28 GHz. The proposed P A also has a compact size occupying only $900mu mathrm{m} {}^{*}500mu mathrm{m}$ in 22nm FDSOI technology including all pads and seal ring.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130597889","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/IWS55252.2022.9977733
Xin Zhao, Changwu Tong, Nan Yang, Kai Lu, Zehai Wu, Y. Long
A decoupled $1times 2$ cylindrical substrate integrated di-electric resonator antennas (DRAs) is presented using metallic vias and rectangular strips. The two externally tangent cylindrical DRAs are implemented in a printed circuit board (PCB) with two different substrate layers, where the upper and the lower sub-strates are used for antenna structure and feed network, respectively. By inserting vertical metallic vias into the upper substrate and attaching horizontal strips at both sides of the intersection, reduced isolation and distorted radiation pattern caused by mu-tual coupling is corrected, resulting in symmetric radiation pat-terns and maximum radiation along z-axis. To verify the idea, a design working at 24.00-24.25 GHz is designed. It can be found that the isolation between the two ports are higher than 15 dB, the envelope correlation coefficient (ECC) is below 0.002, and the maximum radiation is along z-axis, which makes the antenna suit-able for multiple-input and multiple output systems.
{"title":"Radiation Pattern Decoupling of Low-Profile Substrate Integrated Dielectric Resonator Antennas","authors":"Xin Zhao, Changwu Tong, Nan Yang, Kai Lu, Zehai Wu, Y. Long","doi":"10.1109/IWS55252.2022.9977733","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977733","url":null,"abstract":"A decoupled $1times 2$ cylindrical substrate integrated di-electric resonator antennas (DRAs) is presented using metallic vias and rectangular strips. The two externally tangent cylindrical DRAs are implemented in a printed circuit board (PCB) with two different substrate layers, where the upper and the lower sub-strates are used for antenna structure and feed network, respectively. By inserting vertical metallic vias into the upper substrate and attaching horizontal strips at both sides of the intersection, reduced isolation and distorted radiation pattern caused by mu-tual coupling is corrected, resulting in symmetric radiation pat-terns and maximum radiation along z-axis. To verify the idea, a design working at 24.00-24.25 GHz is designed. It can be found that the isolation between the two ports are higher than 15 dB, the envelope correlation coefficient (ECC) is below 0.002, and the maximum radiation is along z-axis, which makes the antenna suit-able for multiple-input and multiple output systems.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116348161","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/IWS55252.2022.9978029
Yijie Niu, Pengzhe Li, Xi Chen, Guifu Zhang, Jianbo Ma
Aiming at the problem of unstable quality and easy interference of millimeter wave human image, this paper proposes a practical method to classify millimeter wave human body images based on imaging characteristics and image features, and then evaluate the effectiveness of the images. By analyzing the causes of abnormal images, the optimized depth residual network model is used to classify the images, and the image effectiveness evaluation problem is transformed into image classification problem. This method fundamentally simplifies the problem of effectiveness evaluation, so that the indexes of effectiveness evaluation can be quantified, so as to realize the dynamic monitoring of human image quality and scanner status in the process of security check. The automatic evaluation method eliminates the hidden security hazards in the automatic mode of the millimeter wave body scanner, and can effectively improve the stability and applicability of the scanner.
{"title":"Research on automatic evaluation method of millimeter wave human image effectiveness","authors":"Yijie Niu, Pengzhe Li, Xi Chen, Guifu Zhang, Jianbo Ma","doi":"10.1109/IWS55252.2022.9978029","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9978029","url":null,"abstract":"Aiming at the problem of unstable quality and easy interference of millimeter wave human image, this paper proposes a practical method to classify millimeter wave human body images based on imaging characteristics and image features, and then evaluate the effectiveness of the images. By analyzing the causes of abnormal images, the optimized depth residual network model is used to classify the images, and the image effectiveness evaluation problem is transformed into image classification problem. This method fundamentally simplifies the problem of effectiveness evaluation, so that the indexes of effectiveness evaluation can be quantified, so as to realize the dynamic monitoring of human image quality and scanner status in the process of security check. The automatic evaluation method eliminates the hidden security hazards in the automatic mode of the millimeter wave body scanner, and can effectively improve the stability and applicability of the scanner.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116506005","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/IWS55252.2022.9977519
J. Yang, Siping Gao, Hao Zhang, Yongxin Guo
Multiple rectifiers (rectennas or arrays) have been widely adopted in nowadays wireless power transfer (WPT) and wire-less energy harvesting (WEH) systems to receive/harvest as much power as possible from multiple power sources. However, few studies focused on the overall RF-to-dc efficiency when combining the DC outputs together under nonuniform RF power inputs. In this paper, we analyze the DC combination problem using an equivalent resistance method for both the series and the shunt combining topologies. We also compare and contrast these two topologies and give some recommendations. ADS harmonic balance solver is employed to verify the proposed analysis method and those recommendations.
{"title":"Analysis of Series and Shunt DC Combination under Nonuniform RF Inputs Using an Equivalent Resistance Method","authors":"J. Yang, Siping Gao, Hao Zhang, Yongxin Guo","doi":"10.1109/IWS55252.2022.9977519","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977519","url":null,"abstract":"Multiple rectifiers (rectennas or arrays) have been widely adopted in nowadays wireless power transfer (WPT) and wire-less energy harvesting (WEH) systems to receive/harvest as much power as possible from multiple power sources. However, few studies focused on the overall RF-to-dc efficiency when combining the DC outputs together under nonuniform RF power inputs. In this paper, we analyze the DC combination problem using an equivalent resistance method for both the series and the shunt combining topologies. We also compare and contrast these two topologies and give some recommendations. ADS harmonic balance solver is employed to verify the proposed analysis method and those recommendations.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124220461","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/IWS55252.2022.9977517
Wanyu Tian, Yuanhe Wang, Chao Zhang
As a new dimension of wireless communication, OAM is considered to have great potential. In order to recognize the Topological Charge (TC) at the receiver of the quantum Orbital Angular Momentum (OAM) communication system, the distortion of vortex electrons under a nonideal magnetic field is theoretically analyzed. The inter-mode crosstalk seriously affects the traditional TC recognition method. Therefore, a lightweight CNN network is designed to realize TC recognition under non-linear distortion, which has a high recognition accuracy.
{"title":"Distortion of Vortex Electrons in a Longitudinal Magnetic Field and OAM Recognition","authors":"Wanyu Tian, Yuanhe Wang, Chao Zhang","doi":"10.1109/IWS55252.2022.9977517","DOIUrl":"https://doi.org/10.1109/IWS55252.2022.9977517","url":null,"abstract":"As a new dimension of wireless communication, OAM is considered to have great potential. In order to recognize the Topological Charge (TC) at the receiver of the quantum Orbital Angular Momentum (OAM) communication system, the distortion of vortex electrons under a nonideal magnetic field is theoretically analyzed. The inter-mode crosstalk seriously affects the traditional TC recognition method. Therefore, a lightweight CNN network is designed to realize TC recognition under non-linear distortion, which has a high recognition accuracy.","PeriodicalId":126964,"journal":{"name":"2022 IEEE MTT-S International Wireless Symposium (IWS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126241967","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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