Pub Date : 2018-12-31DOI: 10.23919/PIERS.2018.8597777
Fariz Azhar Abdillah, E. Rahardjo
In the past few years, there has been a very rapid growth in the demands of communication and data transfer. In order to achieve higher data transfer, it is necessary to apply site-specific planning when designing wireless communication system. We are then focusing on the propagation in site-specific location utilizing ray tracing. This paper discusses the computational simulation of propagation path loss by ray tracing image method when implemented in the urban street canyon and the environment of Universitas Indonesia. This paper focus on analyzing the effect of propagation parameter such as antenna height and wave polarization at 900 MHz, 2.3 GHz and 28 GHz to received signal strength in urban street canyon and Universitas Indonesia. Based on simulation results, path loss exponent at higher transmitter height tend to be lower and path loss exponents at vertical polarization tend to be higher compared to horizontal polarization. In order to increase computation efficiency, we also discuss quantitatively about the convergence of ray numbers in ray tracing method. We found that convergency of reflection can be achieved by considering 2-time reflection for horizontal polarization and 3–4 times reflection for vertical polarizaton. The results from this paper can be utilized as a consideration in effective and efficient site-specific planning for wireless communication system.
{"title":"Study on the Microcellular Radio Wave Propagation at Universitas Indonesia Environment Utilizing Ray Tracing","authors":"Fariz Azhar Abdillah, E. Rahardjo","doi":"10.23919/PIERS.2018.8597777","DOIUrl":"https://doi.org/10.23919/PIERS.2018.8597777","url":null,"abstract":"In the past few years, there has been a very rapid growth in the demands of communication and data transfer. In order to achieve higher data transfer, it is necessary to apply site-specific planning when designing wireless communication system. We are then focusing on the propagation in site-specific location utilizing ray tracing. This paper discusses the computational simulation of propagation path loss by ray tracing image method when implemented in the urban street canyon and the environment of Universitas Indonesia. This paper focus on analyzing the effect of propagation parameter such as antenna height and wave polarization at 900 MHz, 2.3 GHz and 28 GHz to received signal strength in urban street canyon and Universitas Indonesia. Based on simulation results, path loss exponent at higher transmitter height tend to be lower and path loss exponents at vertical polarization tend to be higher compared to horizontal polarization. In order to increase computation efficiency, we also discuss quantitatively about the convergence of ray numbers in ray tracing method. We found that convergency of reflection can be achieved by considering 2-time reflection for horizontal polarization and 3–4 times reflection for vertical polarizaton. The results from this paper can be utilized as a consideration in effective and efficient site-specific planning for wireless communication system.","PeriodicalId":355217,"journal":{"name":"2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129431770","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 : 2018-08-01DOI: 10.23919/PIERS.2018.8598229
S. Shimomura, A. Hirose
We propose an adaptive subsurface visualization system based on a complex-valued self-organizing map (CSOM). Conventionally buried things can be detected in so-called B-scan images obtained by a ground penetrating radar. In contrast, our proposed method is able not only to detect their presence, but also to classify the targets by the self-organizing dynamics in the CSOM. Instead of utilizing only the amplitude information in the time domain, we use both the amplitude and phase information to obtain the scattering coefficients of the targets by use of the phase retrieval method. The CSOM classifies the obtained scattering coefficients to realize an automatic categorization of the targets that scatter the radar electromagnetic wave.
{"title":"Adaptive Subsurface Visualization System Using Phase Retrieval Method and Complex-Valued Self-Organizing Map","authors":"S. Shimomura, A. Hirose","doi":"10.23919/PIERS.2018.8598229","DOIUrl":"https://doi.org/10.23919/PIERS.2018.8598229","url":null,"abstract":"We propose an adaptive subsurface visualization system based on a complex-valued self-organizing map (CSOM). Conventionally buried things can be detected in so-called B-scan images obtained by a ground penetrating radar. In contrast, our proposed method is able not only to detect their presence, but also to classify the targets by the self-organizing dynamics in the CSOM. Instead of utilizing only the amplitude information in the time domain, we use both the amplitude and phase information to obtain the scattering coefficients of the targets by use of the phase retrieval method. The CSOM classifies the obtained scattering coefficients to realize an automatic categorization of the targets that scatter the radar electromagnetic wave.","PeriodicalId":355217,"journal":{"name":"2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama)","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115009974","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 : 2018-08-01DOI: 10.23919/PIERS.2018.8597711
Shengren Fan, Biao Zhang, A. Mouche
Derivation of sea surface wind directions is an important step of sea surface wind fields retrieval from spaceborne Synthetic Aperture Radar (SAR) data. The local gradient (LG) method is used in this paper to retrieve the wind directions of C-band dual-polarization $(VV+VH)$ synthetic aperture radar (SAR) images under tropical cyclone (TC) sea states. We compare wind directions derived from 10 dual-polarization SAR images with collocated wind directions from buoys, scatterometer, radiometer, and Hurricane Research Division (HRD) Realtime Hurricane Wind Analysis System (H*Wind) products. Results show that the wind direction root-mean-square (RMS) error and bias are 19.85° and 0.07° for $VH$ polarization, and 24.89° and −1.26° for $VV$ polarization, suggesting $VH$ is more suitable to exact tropical cyclone wind directions than $VV$.
{"title":"Tropical Cyclone Wind Direction Retrieval from C-Band Dual-Polarization Synthetic Aperture Radar","authors":"Shengren Fan, Biao Zhang, A. Mouche","doi":"10.23919/PIERS.2018.8597711","DOIUrl":"https://doi.org/10.23919/PIERS.2018.8597711","url":null,"abstract":"Derivation of sea surface wind directions is an important step of sea surface wind fields retrieval from spaceborne Synthetic Aperture Radar (SAR) data. The local gradient (LG) method is used in this paper to retrieve the wind directions of C-band dual-polarization <tex>$(VV+VH)$</tex> synthetic aperture radar (SAR) images under tropical cyclone (TC) sea states. We compare wind directions derived from 10 dual-polarization SAR images with collocated wind directions from buoys, scatterometer, radiometer, and Hurricane Research Division (HRD) Realtime Hurricane Wind Analysis System (H*Wind) products. Results show that the wind direction root-mean-square (RMS) error and bias are 19.85° and 0.07° for <tex>$VH$</tex> polarization, and 24.89° and −1.26° for <tex>$VV$</tex> polarization, suggesting <tex>$VH$</tex> is more suitable to exact tropical cyclone wind directions than <tex>$VV$</tex>.","PeriodicalId":355217,"journal":{"name":"2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115640442","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 : 2018-08-01DOI: 10.23919/PIERS.2018.8597745
K. Koshelev, L. Carletti, C. Angelis, Y. Kivshar
We reveal that nonlinear effects at the nanoscale can be enhanced by bound states in the continuum. We demonstrate SHG from subwavelength AlGaAs nanoantennas with record-high conversion efficiency that exceeds by two orders of magnitude the conversion efficiency observed at the conditions of magnetic dipole Mie resonances. This gain is achieved due to the engineering of the mode structure that allows exploiting a high-Q supercavity mode at the fundamental frequency. These results constitute a significant step towards the development of highly-efficient frequency conversion metadevices in the subwavelength circuitry.
{"title":"Giant Nonlinear Response of Subwavelength Dielectric Resonators Enhanced by Bound States in the Continuum","authors":"K. Koshelev, L. Carletti, C. Angelis, Y. Kivshar","doi":"10.23919/PIERS.2018.8597745","DOIUrl":"https://doi.org/10.23919/PIERS.2018.8597745","url":null,"abstract":"We reveal that nonlinear effects at the nanoscale can be enhanced by bound states in the continuum. We demonstrate SHG from subwavelength AlGaAs nanoantennas with record-high conversion efficiency that exceeds by two orders of magnitude the conversion efficiency observed at the conditions of magnetic dipole Mie resonances. This gain is achieved due to the engineering of the mode structure that allows exploiting a high-Q supercavity mode at the fundamental frequency. These results constitute a significant step towards the development of highly-efficient frequency conversion metadevices in the subwavelength circuitry.","PeriodicalId":355217,"journal":{"name":"2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123068421","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 : 2018-08-01DOI: 10.23919/PIERS.2018.8598208
Kewen Pan, T. Leng, Xinyao Zhou, H. Ouslimani, Zhirun Hu
This paper proposed a novel metamaterial inspired long read range UHF RFID tag antenna. A square split ring resonator is acting as a radiator, which operates under electric resonance mode rather than common magnetic resonance one. T-matching network was used to provide a good conjugate matching between UHF RFID chip and the radiator. The maximum read range is over 12 m (EIRP = 4 W). Simulated and measured results are compared and discussed.
提出了一种新型的超材料超高频RFID标签天线。方形开环谐振器作为辐射器，在电谐振模式下工作，而不是普通的磁共振模式。采用t型匹配网络实现了超高频RFID芯片与辐射器之间的良好共轭匹配。最大读取范围超过12 m (EIRP = 4 W)，仿真结果与实测结果进行了比较和讨论。
{"title":"Metamaterial Inspried Long Read Range UHF RFID Tag Antenna","authors":"Kewen Pan, T. Leng, Xinyao Zhou, H. Ouslimani, Zhirun Hu","doi":"10.23919/PIERS.2018.8598208","DOIUrl":"https://doi.org/10.23919/PIERS.2018.8598208","url":null,"abstract":"This paper proposed a novel metamaterial inspired long read range UHF RFID tag antenna. A square split ring resonator is acting as a radiator, which operates under electric resonance mode rather than common magnetic resonance one. T-matching network was used to provide a good conjugate matching between UHF RFID chip and the radiator. The maximum read range is over 12 m (EIRP = 4 W). Simulated and measured results are compared and discussed.","PeriodicalId":355217,"journal":{"name":"2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127143785","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 : 2018-08-01DOI: 10.23919/PIERS.2018.8597712
Z. Miao, Lixin Wu, W. Shi, P. Gamba, M. Jiang
A comprehensive understanding of the spatial distribution of urban settlements is significant to a series of research topics related to environmental and biological changes caused by the urbanization process. Among various technologies, Synthetic Aperture Radar (SAR) has been successfully applied in urban settlement mapping in the past two decades. Although much effort with varying degrees of success has been made in previous studies, the research work is still ongoing, and three challenges should be highlighted. First, the effect of de-speckling is usually underestimated, to the extent that the improvement of the SAR image quality is totally ignored in some studies. Second, a method that combines full Interferometric SAR (InSAR) information is as yet missing. Third, training samples are generally required to process SAR images to extract urban settlements, which is time-consuming and labor-intensive, or even impractical when classifying satellite data at the regional/global scale. To address these issues, this paper presents an automatic method for urban settlement mapping trained by multi-temporal InSAR using social media. To improve the detection performance and reduce false alarm ratio, intensity and coherence are first accurately estimated without loss of image resolution by homogeneous pixel selection and robust estimators. The homogeneous pixels will be also applied to measure urban characteristics from the geometrical prospective. After that, training samples are automatically generated from social media based on the fact that cities and urban areas are nowadays full of individual geo-referenced data such as social network data Finally, these multiple information sources will be fused to extract urban areas based on an improved one class classifier. Experimental results show that the proposed method is effective in extracting urban areas with good accuracy. This study provides a new de-speckling means to process multi-temporal InSAR and sheds new light on the applications of social media in the field of remote sensing.
{"title":"Towards an Automatic Urban Settlement Mapping from Multi-Tomporal InSAR Trained by Social Media","authors":"Z. Miao, Lixin Wu, W. Shi, P. Gamba, M. Jiang","doi":"10.23919/PIERS.2018.8597712","DOIUrl":"https://doi.org/10.23919/PIERS.2018.8597712","url":null,"abstract":"A comprehensive understanding of the spatial distribution of urban settlements is significant to a series of research topics related to environmental and biological changes caused by the urbanization process. Among various technologies, Synthetic Aperture Radar (SAR) has been successfully applied in urban settlement mapping in the past two decades. Although much effort with varying degrees of success has been made in previous studies, the research work is still ongoing, and three challenges should be highlighted. First, the effect of de-speckling is usually underestimated, to the extent that the improvement of the SAR image quality is totally ignored in some studies. Second, a method that combines full Interferometric SAR (InSAR) information is as yet missing. Third, training samples are generally required to process SAR images to extract urban settlements, which is time-consuming and labor-intensive, or even impractical when classifying satellite data at the regional/global scale. To address these issues, this paper presents an automatic method for urban settlement mapping trained by multi-temporal InSAR using social media. To improve the detection performance and reduce false alarm ratio, intensity and coherence are first accurately estimated without loss of image resolution by homogeneous pixel selection and robust estimators. The homogeneous pixels will be also applied to measure urban characteristics from the geometrical prospective. After that, training samples are automatically generated from social media based on the fact that cities and urban areas are nowadays full of individual geo-referenced data such as social network data Finally, these multiple information sources will be fused to extract urban areas based on an improved one class classifier. Experimental results show that the proposed method is effective in extracting urban areas with good accuracy. This study provides a new de-speckling means to process multi-temporal InSAR and sheds new light on the applications of social media in the field of remote sensing.","PeriodicalId":355217,"journal":{"name":"2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama)","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127296536","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 : 2018-08-01DOI: 10.23919/PIERS.2018.8597638
Y. Miyazaki
After the year 1960, mathematical analysis for electromagnetic scattering, diffraction and guided field with complicated boundaries have been developed, based on field analysis methods shown in the previous period around years of 1950. J. A. Kong, K. Hongo and we are belonging to such investigation generation. Millimeter wave and optical technologies have rapidly grown after the coherent millimeter wave devices and lasers have been investigated. Here, some typical studies are shown. Novel mathematical method of integral equation method with conformal mapping is discussed for asymptotic diffraction of electromagnetic field by complicated boundaries, such as an elliptic cylinder perturbed by the circular cylinder. Mode conversions of millimeter wave fields in the waveguide junction between over size circular waveguide and conical horn are investigated by the asymptotic diffraction theory. Field characteristics of the Fabry-Perot resonator with finite circular curved disks are analyzed by the vector integral equations. General scattering and transmission characteristics of beam waves in curved boundaries with wedges are analyzed by spectral function method.
{"title":"Mathematical Analysis of Electromagnetic Guided Propagation and Scattering in Millimeter-Wave and Optical Fields","authors":"Y. Miyazaki","doi":"10.23919/PIERS.2018.8597638","DOIUrl":"https://doi.org/10.23919/PIERS.2018.8597638","url":null,"abstract":"After the year 1960, mathematical analysis for electromagnetic scattering, diffraction and guided field with complicated boundaries have been developed, based on field analysis methods shown in the previous period around years of 1950. J. A. Kong, K. Hongo and we are belonging to such investigation generation. Millimeter wave and optical technologies have rapidly grown after the coherent millimeter wave devices and lasers have been investigated. Here, some typical studies are shown. Novel mathematical method of integral equation method with conformal mapping is discussed for asymptotic diffraction of electromagnetic field by complicated boundaries, such as an elliptic cylinder perturbed by the circular cylinder. Mode conversions of millimeter wave fields in the waveguide junction between over size circular waveguide and conical horn are investigated by the asymptotic diffraction theory. Field characteristics of the Fabry-Perot resonator with finite circular curved disks are analyzed by the vector integral equations. General scattering and transmission characteristics of beam waves in curved boundaries with wedges are analyzed by spectral function method.","PeriodicalId":355217,"journal":{"name":"2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127370292","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 : 2018-08-01DOI: 10.23919/PIERS.2018.8597827
Y. Hou, G. Xiao
An efficient numerical method is proposed to compute the multiscale eletromag-netic scattering problems in this paper. The complex structures are decomposed into several parts and each subdomain is discretized independently. The proposed method relies on using characteristic modes (CM)as macro basis functions which is refered as characteristic mode basis functions (CMBFs)for each subdomain of the object. Each CMBF can be expanded as a linear combination of RWG basis functions and half RWG basis functions which are defined on the boundary edges between adjacent subdomains. It should be noted that CMBFs can be reused when the subdomains share identical or scaling contour feature. In this way, the CMBFs need to be calculated only once for scaling subdomains. Furthermore, rotated subdomain like aircraft's propeller owns the same CMBFs at different rotating angles. Since the number of modes used for each subdomain is much samller than the number of RWG and half RWG basis functions, this metod can lead to a reduced matrix system where the number of unknowns is drastically decreased. In addition, by adopting discontinuous Galerkin schme, the proposed method can handle both conformal and nonconformal discretizations along the tearing lines. (Delete this sentence with red color)Numerical results demonstrate that the proposed method is efficient and accurate in analyzing the multiscale problems.
{"title":"An Efficient Numerical Method for Solving Multiscale Electromagnetic Scattering Problems","authors":"Y. Hou, G. Xiao","doi":"10.23919/PIERS.2018.8597827","DOIUrl":"https://doi.org/10.23919/PIERS.2018.8597827","url":null,"abstract":"An efficient numerical method is proposed to compute the multiscale eletromag-netic scattering problems in this paper. The complex structures are decomposed into several parts and each subdomain is discretized independently. The proposed method relies on using characteristic modes (CM)as macro basis functions which is refered as characteristic mode basis functions (CMBFs)for each subdomain of the object. Each CMBF can be expanded as a linear combination of RWG basis functions and half RWG basis functions which are defined on the boundary edges between adjacent subdomains. It should be noted that CMBFs can be reused when the subdomains share identical or scaling contour feature. In this way, the CMBFs need to be calculated only once for scaling subdomains. Furthermore, rotated subdomain like aircraft's propeller owns the same CMBFs at different rotating angles. Since the number of modes used for each subdomain is much samller than the number of RWG and half RWG basis functions, this metod can lead to a reduced matrix system where the number of unknowns is drastically decreased. In addition, by adopting discontinuous Galerkin schme, the proposed method can handle both conformal and nonconformal discretizations along the tearing lines. (Delete this sentence with red color)Numerical results demonstrate that the proposed method is efficient and accurate in analyzing the multiscale problems.","PeriodicalId":355217,"journal":{"name":"2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124924564","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 : 2018-08-01DOI: 10.23919/PIERS.2018.8598187
Lan Chen, Hai Yang Yin, Tao Wang, He Xu, M. Tong
With the development of the fingerprint identification system, the application field of fingerprint recognition is more and more extensive, and it has an increasingly greater impact on people's lives. Nowadays, the fingerprint identification system in our lives is everywhere and has become an indispensable part of our lives. It can quickly identify our fingerprint features and then tell us the true identity of the fingerprint information. Therefore, people's research on fingerprint identification systems is gradually deepening. This paper mainly studies the image preprocessing algorithm in the fingerprint recognition system. In the process of fingerprint identification system, the read image must be preprocessed to make the image clearer and less noise, which is convenient for fingerprint recognition and feature extraction. This paper focuses on the fingerprint image enhancement algorithm, based on the Gabor filter design of the empty filler on the fingerprint image preprocessing, based on the reduction of image enhancement, leaving a large number of holes, fingerprint images with fewer false feature points, improve the follow-up feature points. The speed and accuracy of the extraction algorithm.
{"title":"An Improved Algorithm for Enhancing Fingerprint Image Quality","authors":"Lan Chen, Hai Yang Yin, Tao Wang, He Xu, M. Tong","doi":"10.23919/PIERS.2018.8598187","DOIUrl":"https://doi.org/10.23919/PIERS.2018.8598187","url":null,"abstract":"With the development of the fingerprint identification system, the application field of fingerprint recognition is more and more extensive, and it has an increasingly greater impact on people's lives. Nowadays, the fingerprint identification system in our lives is everywhere and has become an indispensable part of our lives. It can quickly identify our fingerprint features and then tell us the true identity of the fingerprint information. Therefore, people's research on fingerprint identification systems is gradually deepening. This paper mainly studies the image preprocessing algorithm in the fingerprint recognition system. In the process of fingerprint identification system, the read image must be preprocessed to make the image clearer and less noise, which is convenient for fingerprint recognition and feature extraction. This paper focuses on the fingerprint image enhancement algorithm, based on the Gabor filter design of the empty filler on the fingerprint image preprocessing, based on the reduction of image enhancement, leaving a large number of holes, fingerprint images with fewer false feature points, improve the follow-up feature points. The speed and accuracy of the extraction algorithm.","PeriodicalId":355217,"journal":{"name":"2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124947294","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 : 2018-08-01DOI: 10.23919/PIERS.2018.8598228
A. Tsvetkov, Y. Bykov, A. G. Ererneev, A. Luchinin, V. Manuilov, I. Plotnikov, M. Morozkin, M. Proyavin, V. Holoptsev, M. Glyavin
The report presents review of technological gyrotron systems developed and made by Institute of Applied Physics of the Russian Academy of Sciences (lAP RAS) jointly with GYCOM Ltd. (Nizhny Novgorod, Russia). Typical microwave power of these systems is several tens kW with efficiency up to 0.4 (0.65 in the case of depressed collector) at the frequency range 24–45 GHz. The output power of gyrotrons can be smoothly regulated from about 5% to 100% of the full power. All CW gyrotrons can operate also in pulse regime with the same or slightly higher output power.
{"title":"Gyrotron-Based Microwave Systems for Technological Applications: Recent Experiments and New Designs","authors":"A. Tsvetkov, Y. Bykov, A. G. Ererneev, A. Luchinin, V. Manuilov, I. Plotnikov, M. Morozkin, M. Proyavin, V. Holoptsev, M. Glyavin","doi":"10.23919/PIERS.2018.8598228","DOIUrl":"https://doi.org/10.23919/PIERS.2018.8598228","url":null,"abstract":"The report presents review of technological gyrotron systems developed and made by Institute of Applied Physics of the Russian Academy of Sciences (lAP RAS) jointly with GYCOM Ltd. (Nizhny Novgorod, Russia). Typical microwave power of these systems is several tens kW with efficiency up to 0.4 (0.65 in the case of depressed collector) at the frequency range 24–45 GHz. The output power of gyrotrons can be smoothly regulated from about 5% to 100% of the full power. All CW gyrotrons can operate also in pulse regime with the same or slightly higher output power.","PeriodicalId":355217,"journal":{"name":"2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama)","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126168188","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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