Pub Date : 2022-04-25DOI: 10.1109/piers55526.2022.9793284
T. Hejtmánek, P. Drexler, M. Škoda
Nuclear power plants are one of the largest producers of electricity. To remotely transmit this energy, they use the transformation of electrical voltage to higher levels using power transformers. Decommissioning such a transformer result in very high financial losses. One of the influences affecting the life and function of transformers is the activity of so-called partial discharges (PD). One of the electrical allocutions of partial discharges is the emission of broadband electromagnetic signals in the ultra-high frequency (UHF) band. This specific manifestation of partial discharge is used by the UHF method of partial discharge detection, which is very useful in terms of evaluating the state of insulation. In this paper we present methods for simulating partial discharges in transformer oil. Very thin cannulas and gas with lower electrical strength than air was used to develop the bubbles to reduce the voltage required to form PD. A simulation device for the generation of partial discharges has been proposed, realized in a vessel filled with transformer oil, in which gas bubbles with lower electrical strength are formed, in which the discharge activity will be initiated by means of electrodes with a spherical cross-section. This arrangement is supplemented by measuring apparatus for sensing, recording and subsequent analysis of signals emitted by PD. In the simulation program Ansys Maxwell, simulations of the gas bubble between the electrodes in the transformer oil were performed. The work also deals with the comparison of the achieved results for different antennas in the time and frequency domain.
{"title":"Simulator of UHF Signal of the Partial Discharge","authors":"T. Hejtmánek, P. Drexler, M. Škoda","doi":"10.1109/piers55526.2022.9793284","DOIUrl":"https://doi.org/10.1109/piers55526.2022.9793284","url":null,"abstract":"Nuclear power plants are one of the largest producers of electricity. To remotely transmit this energy, they use the transformation of electrical voltage to higher levels using power transformers. Decommissioning such a transformer result in very high financial losses. One of the influences affecting the life and function of transformers is the activity of so-called partial discharges (PD). One of the electrical allocutions of partial discharges is the emission of broadband electromagnetic signals in the ultra-high frequency (UHF) band. This specific manifestation of partial discharge is used by the UHF method of partial discharge detection, which is very useful in terms of evaluating the state of insulation. In this paper we present methods for simulating partial discharges in transformer oil. Very thin cannulas and gas with lower electrical strength than air was used to develop the bubbles to reduce the voltage required to form PD. A simulation device for the generation of partial discharges has been proposed, realized in a vessel filled with transformer oil, in which gas bubbles with lower electrical strength are formed, in which the discharge activity will be initiated by means of electrodes with a spherical cross-section. This arrangement is supplemented by measuring apparatus for sensing, recording and subsequent analysis of signals emitted by PD. In the simulation program Ansys Maxwell, simulations of the gas bubble between the electrodes in the transformer oil were performed. The work also deals with the comparison of the achieved results for different antennas in the time and frequency domain.","PeriodicalId":422383,"journal":{"name":"2022 Photonics & Electromagnetics Research Symposium (PIERS)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134603544","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 : 2022-04-25DOI: 10.1109/piers55526.2022.9792907
Yury G. Pasternak, V. Pendyurin, S. Fedorov
This paper presents the results of numerical electrodynamic simulation of multi-beam antenna systems for full-azimuth and hemispherical scan coverage operating in the frequency range of 27–29GHz. Both antennas can be manufactured using multilayer PCB technology. Antenna system for full-azimuth scan coverage can form 16 beams with directivity about 10–11dBi. The hemispherical antenna has a minimum gain in azimuthal plane of 4dBi and a maximum gain of about 9.5dBi. The polarization of this antenna can be arbitrary and is determined by the type of feeds of the metamaterial lens.
{"title":"Compact Multi-beam Antennas for Full-azimuth and Hemispherical Scan Coverage","authors":"Yury G. Pasternak, V. Pendyurin, S. Fedorov","doi":"10.1109/piers55526.2022.9792907","DOIUrl":"https://doi.org/10.1109/piers55526.2022.9792907","url":null,"abstract":"This paper presents the results of numerical electrodynamic simulation of multi-beam antenna systems for full-azimuth and hemispherical scan coverage operating in the frequency range of 27–29GHz. Both antennas can be manufactured using multilayer PCB technology. Antenna system for full-azimuth scan coverage can form 16 beams with directivity about 10–11dBi. The hemispherical antenna has a minimum gain in azimuthal plane of 4dBi and a maximum gain of about 9.5dBi. The polarization of this antenna can be arbitrary and is determined by the type of feeds of the metamaterial lens.","PeriodicalId":422383,"journal":{"name":"2022 Photonics & Electromagnetics Research Symposium (PIERS)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133312881","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 : 2022-04-25DOI: 10.1109/piers55526.2022.9793294
Maxim A. Dubovitskiy
Utilization of multiple-input multiple-output (MIMO) systems as a means of increasing channel capacity has been an area of increasing consideration in radio communications. This research is important because high-frequency communication using MIMO allows for international communication at long distances using lower power consumption than many other approaches. The objective of this research is to develop and implement software algorithms for the synthesis of MIMO-type arrays, which entail an increase in the efficiency of their operation, including the suppression of side lobes by optimizing their structures, taking into account the interference of electromagnetic waves between neighboring elements, increasing the signal-to-noise ratio (SNR) at the receiver input, increasing the bandwidth of the receiving and transmitting modules of LTE/5G communication systems. Since it is assumed that 6G communication networks will use the terahertz and sub-terahertz frequency ranges and provide a significantly lower level of delay in data transmission than 5G/IMT-2020 networks, the proposed Machine Learning (ML) algorithms should be universal and capable of providing computer-aided design of aperiodic multi-element antenna arrays not only in existing LTE/5G communication systems, but also in the terahertz frequency range.
{"title":"Machine Learning Based MIMO Antenna Arrays Optimization for 5G/6G","authors":"Maxim A. Dubovitskiy","doi":"10.1109/piers55526.2022.9793294","DOIUrl":"https://doi.org/10.1109/piers55526.2022.9793294","url":null,"abstract":"Utilization of multiple-input multiple-output (MIMO) systems as a means of increasing channel capacity has been an area of increasing consideration in radio communications. This research is important because high-frequency communication using MIMO allows for international communication at long distances using lower power consumption than many other approaches. The objective of this research is to develop and implement software algorithms for the synthesis of MIMO-type arrays, which entail an increase in the efficiency of their operation, including the suppression of side lobes by optimizing their structures, taking into account the interference of electromagnetic waves between neighboring elements, increasing the signal-to-noise ratio (SNR) at the receiver input, increasing the bandwidth of the receiving and transmitting modules of LTE/5G communication systems. Since it is assumed that 6G communication networks will use the terahertz and sub-terahertz frequency ranges and provide a significantly lower level of delay in data transmission than 5G/IMT-2020 networks, the proposed Machine Learning (ML) algorithms should be universal and capable of providing computer-aided design of aperiodic multi-element antenna arrays not only in existing LTE/5G communication systems, but also in the terahertz frequency range.","PeriodicalId":422383,"journal":{"name":"2022 Photonics & Electromagnetics Research Symposium (PIERS)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132574696","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 : 2022-04-25DOI: 10.1109/piers55526.2022.9792855
Shuangshang Zhang, Qinghong Xu, Xiaofeng Li
In this study, we proposed an automatic waterline signature extraction method based on deep convolutional neural networks (DCNNs). Our objective is to provide a rapid and straightforward to use method that can tackle the waterline signature extraction from large-scale tidal flats in Sentinel-1 SAR images without re-training or manual interference. The statistical results show this DCNN-based method has appreciable accuracy for efficient extraction of waterline in SAR images even under complex imaging conditions (the mean precision and recall are 0.81 and 0.88, respectively), implying that this method is potential for rapid analysis of tidal flat topography evolution by using the waterline method.
{"title":"Automatic Waterline Extraction of Tidal Flats from SAR Images Based on Deep Convolutional Neural Networks","authors":"Shuangshang Zhang, Qinghong Xu, Xiaofeng Li","doi":"10.1109/piers55526.2022.9792855","DOIUrl":"https://doi.org/10.1109/piers55526.2022.9792855","url":null,"abstract":"In this study, we proposed an automatic waterline signature extraction method based on deep convolutional neural networks (DCNNs). Our objective is to provide a rapid and straightforward to use method that can tackle the waterline signature extraction from large-scale tidal flats in Sentinel-1 SAR images without re-training or manual interference. The statistical results show this DCNN-based method has appreciable accuracy for efficient extraction of waterline in SAR images even under complex imaging conditions (the mean precision and recall are 0.81 and 0.88, respectively), implying that this method is potential for rapid analysis of tidal flat topography evolution by using the waterline method.","PeriodicalId":422383,"journal":{"name":"2022 Photonics & Electromagnetics Research Symposium (PIERS)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116930243","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}
In this paper, a new structure of tunable dipole antenna that controlled by motor is proposed. Based on half-wave dipole antenna, this antenna adds a motor-controlled rotating structure in the middle of the dipole. By changing the length of the loop arm connected to the dipole arm, the continuous adjustment of the working frequency is realized. The structure can work effectively in various frequency bands, and shows different tunable ranges according to different sizes and ratios. In a specific implementation, simulation results show that the antenna has a tunable range of 847MHz to 930MHz and a minimum -10 dB bandwidth of 108 MHz. The radiation pattern of the antenna has a directivity from 2.27 dBi to 2.18 dBi and a 3 dB beamwidth from 77.5° to 79.0°. All point to the good application potential of this design in wireless communication fields such as RFID readers.
{"title":"A Tunable Dipole Antenna Controlled by Motor","authors":"Tingjun Lai, Xinyu Hong, Yinger Zhang, Zhen-Ji Huang, Hengjian Ma, J. Huangfu","doi":"10.1109/piers55526.2022.9793289","DOIUrl":"https://doi.org/10.1109/piers55526.2022.9793289","url":null,"abstract":"In this paper, a new structure of tunable dipole antenna that controlled by motor is proposed. Based on half-wave dipole antenna, this antenna adds a motor-controlled rotating structure in the middle of the dipole. By changing the length of the loop arm connected to the dipole arm, the continuous adjustment of the working frequency is realized. The structure can work effectively in various frequency bands, and shows different tunable ranges according to different sizes and ratios. In a specific implementation, simulation results show that the antenna has a tunable range of 847MHz to 930MHz and a minimum -10 dB bandwidth of 108 MHz. The radiation pattern of the antenna has a directivity from 2.27 dBi to 2.18 dBi and a 3 dB beamwidth from 77.5° to 79.0°. All point to the good application potential of this design in wireless communication fields such as RFID readers.","PeriodicalId":422383,"journal":{"name":"2022 Photonics & Electromagnetics Research Symposium (PIERS)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116318813","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 : 2022-04-25DOI: 10.1109/piers55526.2022.9792669
T. Roth, W. C. Chew
Currently, circuit quantum electrodynamics architectures have emerged as one of the most popular approaches to implement practical quantum information processing hardware. Although significant progress has been made, many technical issues remain that limit the performance of fabricated devices. One approach to accelerate progress in the engineering design of these devices is to develop improved numerical modeling methods. Current modeling methods generally rely on approximate lumped element circuit models to describe the complex network of microwave transmission lines required to operate a circuit quantum electrodynamics device. This reduction in complexity in the theoretical model is valuable for gaining insight into the operation of a device, but does limit the opportunity for using these models to optimize the performance of practical devices. To develop rigorous numerical modeling methods, it is necessary to move toward theoretical descriptions of circuit quantum electrodynamics devices that retain the full details of the three-dimensional vector electromagnetic fields that exist in these systems. In this work, we present details on such a theoretical model for one of the most commonly used circuit quantum electrodynamics systems, a transmon qubit coupled to microwave transmission lines. We discuss the quantization of our new model and show that by adopting relevant approximations our model can be reduced to the same lumped element descriptions commonly used in the literature. We also discuss the derivation of quantum equations of motion for the coupled field-transmon system, which can be used as the starting point for developing full-wave numerical solvers for these circuit quantum electrodynamics systems in the future.
{"title":"Field-based Description of the Coupling between a Transmon Qubit and a Transmission Line Geometry","authors":"T. Roth, W. C. Chew","doi":"10.1109/piers55526.2022.9792669","DOIUrl":"https://doi.org/10.1109/piers55526.2022.9792669","url":null,"abstract":"Currently, circuit quantum electrodynamics architectures have emerged as one of the most popular approaches to implement practical quantum information processing hardware. Although significant progress has been made, many technical issues remain that limit the performance of fabricated devices. One approach to accelerate progress in the engineering design of these devices is to develop improved numerical modeling methods. Current modeling methods generally rely on approximate lumped element circuit models to describe the complex network of microwave transmission lines required to operate a circuit quantum electrodynamics device. This reduction in complexity in the theoretical model is valuable for gaining insight into the operation of a device, but does limit the opportunity for using these models to optimize the performance of practical devices. To develop rigorous numerical modeling methods, it is necessary to move toward theoretical descriptions of circuit quantum electrodynamics devices that retain the full details of the three-dimensional vector electromagnetic fields that exist in these systems. In this work, we present details on such a theoretical model for one of the most commonly used circuit quantum electrodynamics systems, a transmon qubit coupled to microwave transmission lines. We discuss the quantization of our new model and show that by adopting relevant approximations our model can be reduced to the same lumped element descriptions commonly used in the literature. We also discuss the derivation of quantum equations of motion for the coupled field-transmon system, which can be used as the starting point for developing full-wave numerical solvers for these circuit quantum electrodynamics systems in the future.","PeriodicalId":422383,"journal":{"name":"2022 Photonics & Electromagnetics Research Symposium (PIERS)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123677064","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 : 2022-04-25DOI: 10.1109/piers55526.2022.9793210
Haoran Wang, S. Chen, W. Dai, Xun Cai, H. Fu
A photonic crystal fiber (PCF) based surface plasmon resonance (SPR) refractive index (RI) sensor is proposed and demonstrated. The gold as a plasmonic material is coated outside of the PCF to realize RI sensing and the influence of various geometrical parameters on the sensing characteristics are investigated by using finite element method (FEM). Results show that the proposed sensor realizes a maximum wavelength sensitivity (WS) of 10300nm/RIU with a wavelength resolution of 7.767 × 10−6. Moreover, the maximum amplitude sensitivity (AS) of 3465 RIU−1 is realized in the detection range from 1.33 to 1.41. This biosensor exhibits high sensitivity, simple structure and convenient detection, which is very suitable for the bio-sensing or diagnosis of cancers.
{"title":"A High Sensitivity Surface Plasmon Resonance Biosensor Based on Photonic Crystal Fibers for Refractive Index Sensing","authors":"Haoran Wang, S. Chen, W. Dai, Xun Cai, H. Fu","doi":"10.1109/piers55526.2022.9793210","DOIUrl":"https://doi.org/10.1109/piers55526.2022.9793210","url":null,"abstract":"A photonic crystal fiber (PCF) based surface plasmon resonance (SPR) refractive index (RI) sensor is proposed and demonstrated. The gold as a plasmonic material is coated outside of the PCF to realize RI sensing and the influence of various geometrical parameters on the sensing characteristics are investigated by using finite element method (FEM). Results show that the proposed sensor realizes a maximum wavelength sensitivity (WS) of 10300nm/RIU with a wavelength resolution of 7.767 × 10−6. Moreover, the maximum amplitude sensitivity (AS) of 3465 RIU−1 is realized in the detection range from 1.33 to 1.41. This biosensor exhibits high sensitivity, simple structure and convenient detection, which is very suitable for the bio-sensing or diagnosis of cancers.","PeriodicalId":422383,"journal":{"name":"2022 Photonics & Electromagnetics Research Symposium (PIERS)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117232900","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}
In this paper, a S-band widebeam waveguide slot cavity antenna with out-of-band anti-interference function is introduced. Firstly, it uses the eigenmode simulation to observe the cut-off frequencies of various modes and adjusts the relevant parameters to achieve the desired passband and stopband. Then, four radiation slots are etched on cavity, and the parameters are adjusted for widebeam and impedance matching. Finally, the simulation results are presented and discussed. The results show that the proposed antenna has the 10 dB impedance bandwidth from 2.96 GHz to 3.05 GHz, the 3 dB beamwidth of 110°, and gain suppression of 10 ~ 35 dB compared with that without filtering units in stopband.
{"title":"Design of a Wide-beam Waveguide Slot Antenna for Anti-interference Applications","authors":"Hongji Li, Xiaohan Zhang, Xue Chen, R. Jin, Jun-ping Geng, Xianling Liang","doi":"10.1109/PIERS55526.2022.9793271","DOIUrl":"https://doi.org/10.1109/PIERS55526.2022.9793271","url":null,"abstract":"In this paper, a S-band widebeam waveguide slot cavity antenna with out-of-band anti-interference function is introduced. Firstly, it uses the eigenmode simulation to observe the cut-off frequencies of various modes and adjusts the relevant parameters to achieve the desired passband and stopband. Then, four radiation slots are etched on cavity, and the parameters are adjusted for widebeam and impedance matching. Finally, the simulation results are presented and discussed. The results show that the proposed antenna has the 10 dB impedance bandwidth from 2.96 GHz to 3.05 GHz, the 3 dB beamwidth of 110°, and gain suppression of 10 ~ 35 dB compared with that without filtering units in stopband.","PeriodicalId":422383,"journal":{"name":"2022 Photonics & Electromagnetics Research Symposium (PIERS)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123900325","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 : 2022-04-25DOI: 10.1109/piers55526.2022.9792844
Jian‐Yun Gao, Xiang-hua Wang
In this paper, we make an extension of the conventional two-step locally one-dimensional finite-difference time-domain method (LOD-FDTD) to simulate the magnetostatic field biased graphene sheet. Unlike the LOD-FDTD method developed recently, the proposed one calculates the isotropic part of the surface conductivity of the graphene with the two-step LOD-FDTD method and a simple extra computation process for the anisotropic part. To check the accuracy and efficiency, we carried out numerical experiments and the total transmission coefficient of the magnetized graphene sheet were calculated. It is found that the results computed by our proposed LOD-FDTD method are more accurate than the conventional two-step LOD-FDTD method with almost the same computational time.
{"title":"Extension of the LOD-FDTD Method to Accurately Investigate the Transmission Properties of the Magnetized Graphene-based Structures","authors":"Jian‐Yun Gao, Xiang-hua Wang","doi":"10.1109/piers55526.2022.9792844","DOIUrl":"https://doi.org/10.1109/piers55526.2022.9792844","url":null,"abstract":"In this paper, we make an extension of the conventional two-step locally one-dimensional finite-difference time-domain method (LOD-FDTD) to simulate the magnetostatic field biased graphene sheet. Unlike the LOD-FDTD method developed recently, the proposed one calculates the isotropic part of the surface conductivity of the graphene with the two-step LOD-FDTD method and a simple extra computation process for the anisotropic part. To check the accuracy and efficiency, we carried out numerical experiments and the total transmission coefficient of the magnetized graphene sheet were calculated. It is found that the results computed by our proposed LOD-FDTD method are more accurate than the conventional two-step LOD-FDTD method with almost the same computational time.","PeriodicalId":422383,"journal":{"name":"2022 Photonics & Electromagnetics Research Symposium (PIERS)","volume":"429 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125842646","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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