Pub Date : 2015-11-01DOI: 10.1109/LAPC.2015.7366115
F. Puggelli, G. Minatti, Y. Vardaxoglou, S. Maci
A special kind of spiral planar circularly polarised (CP) antenna is presented. These antennas are based on an interaction between a cylindrical surface wave excited by an omnidirectional probe and an inhomogeneous surface impedance with a spiral pattern. The surface impedance interaction transforms a bounded TM0 surface wave into a circularly polarised leaky wave with almost broadside radiation, through a grounded dielectric slab with a spiral sinusoidal thickness, modulated in the radial direction by a polynomial. Full wave results are in perfect agreement with the theory previously outlined in the literature.
{"title":"Design of a modulated dielectric metasurface antenna","authors":"F. Puggelli, G. Minatti, Y. Vardaxoglou, S. Maci","doi":"10.1109/LAPC.2015.7366115","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366115","url":null,"abstract":"A special kind of spiral planar circularly polarised (CP) antenna is presented. These antennas are based on an interaction between a cylindrical surface wave excited by an omnidirectional probe and an inhomogeneous surface impedance with a spiral pattern. The surface impedance interaction transforms a bounded TM0 surface wave into a circularly polarised leaky wave with almost broadside radiation, through a grounded dielectric slab with a spiral sinusoidal thickness, modulated in the radial direction by a polynomial. Full wave results are in perfect agreement with the theory previously outlined in the literature.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116283587","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366000
Kansheng Yang, X. Bao, M. Ammann
A back-to-back linearly polarized patch antenna with a single microstrip line feed is proposed for WLAN applications. The antenna consists of two identical rectangular patch elements on the front and rear sides of a common ground plane. One patch antenna can be switched on at a time using a single-pole double-throw PIN diode switching circuit, offering a switched pattern angle of 180° in the Z-axis.
{"title":"A back-to-back beam switching microstrip patch antenna","authors":"Kansheng Yang, X. Bao, M. Ammann","doi":"10.1109/LAPC.2015.7366000","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366000","url":null,"abstract":"A back-to-back linearly polarized patch antenna with a single microstrip line feed is proposed for WLAN applications. The antenna consists of two identical rectangular patch elements on the front and rear sides of a common ground plane. One patch antenna can be switched on at a time using a single-pole double-throw PIN diode switching circuit, offering a switched pattern angle of 180° in the Z-axis.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116833655","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366025
E. Kowalczuk, R. Seager, C. Panagamuwa
A series of 3D EM simulation models are presented in order to determine the effect that conductivity profile, passivation layer and connection method have on the transmission performance of a photoconductive microwave switch. The use of 3D EM simulation can help quantify the benefit and impact of different approaches before the manufacture stage. The aim is to find methods to reduce insertion loss of the switch to provide maximum efficiency when the device is integrated into reconfigurable applications. Results show improvement to the transmission is possible by altering passivation thickness and designing optical feed to maintain signal planarity.
{"title":"Investigating factors affecting photoconductive microwave switch performance using 3D EM simulation","authors":"E. Kowalczuk, R. Seager, C. Panagamuwa","doi":"10.1109/LAPC.2015.7366025","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366025","url":null,"abstract":"A series of 3D EM simulation models are presented in order to determine the effect that conductivity profile, passivation layer and connection method have on the transmission performance of a photoconductive microwave switch. The use of 3D EM simulation can help quantify the benefit and impact of different approaches before the manufacture stage. The aim is to find methods to reduce insertion loss of the switch to provide maximum efficiency when the device is integrated into reconfigurable applications. Results show improvement to the transmission is possible by altering passivation thickness and designing optical feed to maintain signal planarity.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117206602","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366124
T. Tuovinen, M. Berg, A. Parssinen, E. Salonen
In future's massive multiple-input multiple-output (MIMO) systems, the usage of antenna arrays has a centre stage solving the dilemma of a link range vs. a data rate. From wearable application perspective, proposed antennas in open literature have been mainly passive single element configurations which are optimised for either off-or on-body communication purposes. Arrays can bring fundamental improvements for the purposes of a wireless body area network (WBAN) by enabling possibility to realize an electronically switchable on/off-body communication antenna configuration. As recent trends in wearable market have shown that cellular communications are becoming products, the purpose of this article is to present the potential of a small and relative simple array configuration for switchable on/off-body communications. In this paper, free space channel path gain S21 is compared for the antennas at 2.4 GHz with respect to an array at 10 GHz with the equal aperture. Body tissue characteristics are compared, too. The functionality of the proposed array is shown in terms of beam steering capability, E-field distributions and various E-field (Ex, Ey, Ez, and Eabs) components along a body phantom model.
{"title":"Potential of a small array at 10 GHz for switchable on/off-body wearable sensor node purposes","authors":"T. Tuovinen, M. Berg, A. Parssinen, E. Salonen","doi":"10.1109/LAPC.2015.7366124","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366124","url":null,"abstract":"In future's massive multiple-input multiple-output (MIMO) systems, the usage of antenna arrays has a centre stage solving the dilemma of a link range vs. a data rate. From wearable application perspective, proposed antennas in open literature have been mainly passive single element configurations which are optimised for either off-or on-body communication purposes. Arrays can bring fundamental improvements for the purposes of a wireless body area network (WBAN) by enabling possibility to realize an electronically switchable on/off-body communication antenna configuration. As recent trends in wearable market have shown that cellular communications are becoming products, the purpose of this article is to present the potential of a small and relative simple array configuration for switchable on/off-body communications. In this paper, free space channel path gain S21 is compared for the antennas at 2.4 GHz with respect to an array at 10 GHz with the equal aperture. Body tissue characteristics are compared, too. The functionality of the proposed array is shown in terms of beam steering capability, E-field distributions and various E-field (Ex, Ey, Ez, and Eabs) components along a body phantom model.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122355360","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366101
A. Elazreg, Mohamed A. Shrud, A. Kharaz
This paper presents a half-duplex amplify-and-forward (AF) two-way wireless relay networks (TWRNs) with two terminal nodes and two relay nodes each having two antennas. A distributed extended orthogonal space time block coding (D-EOSTBC) with one-bit feedback scheme based on the selection of phase rotation has been implemented. In this feedback scheme, only one-bit feedback is applied at the relay nodes to extract full cooperative diversity gain and array gain at each terminal node. The transmission symbols from the antennas of each relay node are rotated according to the feedback from the terminal nodes which is equivalent to rotating the phases of the corresponding channel coefficients. The simulation results show that the one-bit feedback scheme achieves an improved system performance with lower feedback overhead compared to previously reported feedback schemes.
{"title":"Distributed EO-STBC with one-bit feedback scheme for bi-directional cooperative wireless dual-antenna relay networks","authors":"A. Elazreg, Mohamed A. Shrud, A. Kharaz","doi":"10.1109/LAPC.2015.7366101","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366101","url":null,"abstract":"This paper presents a half-duplex amplify-and-forward (AF) two-way wireless relay networks (TWRNs) with two terminal nodes and two relay nodes each having two antennas. A distributed extended orthogonal space time block coding (D-EOSTBC) with one-bit feedback scheme based on the selection of phase rotation has been implemented. In this feedback scheme, only one-bit feedback is applied at the relay nodes to extract full cooperative diversity gain and array gain at each terminal node. The transmission symbols from the antennas of each relay node are rotated according to the feedback from the terminal nodes which is equivalent to rotating the phases of the corresponding channel coefficients. The simulation results show that the one-bit feedback scheme achieves an improved system performance with lower feedback overhead compared to previously reported feedback schemes.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125337241","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366045
L. Scialacqua, L. Foged, F. Saccardi, G. Vecchi, J. A. Araque Quijano, P. Duxbury
The equivalent current (EQC) technique applied on antenna measurements has been demonstrated to be an efficient tool for diagnostics in many measurement situations [15]. Indeed the equivalent currents can be applied in tasks such as the filtering of disturbances such as undesired coupling with the supporting structure or the feeding and in NF-NF transformation. In particular the filtering capabilities have been efficiently demonstrated for suppressing the disturbances due to the presence of the feeding cable and of the mounting support in the measurement set-up in a sleeve dipole and a TT&C antenna [6]. The study was focused on the analysis of the co-polar component of the radiated field. Starting from the past results [6] we present in this paper a new study of the TT&C antenna extended also to the diagnostic of the cross-polar antenna sources.
{"title":"Advanced cross polar source diagnostics based on the equivalent currents reconstruction from measured data","authors":"L. Scialacqua, L. Foged, F. Saccardi, G. Vecchi, J. A. Araque Quijano, P. Duxbury","doi":"10.1109/LAPC.2015.7366045","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366045","url":null,"abstract":"The equivalent current (EQC) technique applied on antenna measurements has been demonstrated to be an efficient tool for diagnostics in many measurement situations [15]. Indeed the equivalent currents can be applied in tasks such as the filtering of disturbances such as undesired coupling with the supporting structure or the feeding and in NF-NF transformation. In particular the filtering capabilities have been efficiently demonstrated for suppressing the disturbances due to the presence of the feeding cable and of the mounting support in the measurement set-up in a sleeve dipole and a TT&C antenna [6]. The study was focused on the analysis of the co-polar component of the radiated field. Starting from the past results [6] we present in this paper a new study of the TT&C antenna extended also to the diagnostic of the cross-polar antenna sources.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125391437","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366104
L. A. Garza, M. Panduro, D. Covarrubias
The large bandwidth available for ultra wideband (UWB) communications considerably complicates the design of antenna arrays in the frequency domain perspective. The design of antenna arrays in a time-domain perspective is an alternative way for this design problem. This paper presents the synthesis of time-domain circular antenna arrays for a flat-top energy pattern. The synthesis regards the optimal true-time exciting delays and optimal exciting amplitudes by using the well-known Differential Evolution for Multiobjetive Optimization (DEMO). The results show a good performance of the energy pattern for an optimized circular antenna array and the performance in the frequency domain time domain synthesis.
{"title":"Time-domain synthesis of UWB circular antenna array for flat-top patterns","authors":"L. A. Garza, M. Panduro, D. Covarrubias","doi":"10.1109/LAPC.2015.7366104","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366104","url":null,"abstract":"The large bandwidth available for ultra wideband (UWB) communications considerably complicates the design of antenna arrays in the frequency domain perspective. The design of antenna arrays in a time-domain perspective is an alternative way for this design problem. This paper presents the synthesis of time-domain circular antenna arrays for a flat-top energy pattern. The synthesis regards the optimal true-time exciting delays and optimal exciting amplitudes by using the well-known Differential Evolution for Multiobjetive Optimization (DEMO). The results show a good performance of the energy pattern for an optimized circular antenna array and the performance in the frequency domain time domain synthesis.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127556012","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366083
S. Koziel, A. Bekasiewicz, Selvakumar Ulaganathan, T. Dhaene
In this paper, a methodology for rapid design optimization of an ultra-wideband (UWB) monopole antenna with a lower WLAN band-notch is presented. The band-notch is realized using an open loop resonator implemented in the radiation patch of the antenna. Design optimization is a two stage process, with the first stage focused on the design of the antenna itself, and the second stage aiming at identification of the appropriate dimensions of the resonator with the purpose of allocating the band-notch in the desired frequency range. Both optimization stages are realized using surrogate-based optimization involving variable-fidelity electromagnetic (EM) simulation models as well as an additive response correction (first stage), and sequential approximate optimization (second stage). The final antenna design is obtained at the CPU cost corresponding to only 23 high-fidelity EM antenna simulations.
{"title":"Fast design optimization of UWB antenna with WLAN band-notch","authors":"S. Koziel, A. Bekasiewicz, Selvakumar Ulaganathan, T. Dhaene","doi":"10.1109/LAPC.2015.7366083","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366083","url":null,"abstract":"In this paper, a methodology for rapid design optimization of an ultra-wideband (UWB) monopole antenna with a lower WLAN band-notch is presented. The band-notch is realized using an open loop resonator implemented in the radiation patch of the antenna. Design optimization is a two stage process, with the first stage focused on the design of the antenna itself, and the second stage aiming at identification of the appropriate dimensions of the resonator with the purpose of allocating the band-notch in the desired frequency range. Both optimization stages are realized using surrogate-based optimization involving variable-fidelity electromagnetic (EM) simulation models as well as an additive response correction (first stage), and sequential approximate optimization (second stage). The final antenna design is obtained at the CPU cost corresponding to only 23 high-fidelity EM antenna simulations.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132217675","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366105
P. Gkonis, D. Kaklamani, I. Venieris, C. Dervos, M. Chrysomallis
The goal of the study presented in this paper is to investigate the performance of a new transmission strategy for MIMO-WCDMA networks operating in spatial multiplexing transmission mode, based on Principal Component Analysis (PCA) at the reception. In this context, all individual multipath components are first processed by a space - time RAKE receiver, and then PCA is employed on the received data matrix. The maximum eigenvalue along with the corresponding eigenvector are fed back to the transmitter, who formulates a modified correlation matrix. This matrix is used in order to determine the significant terms that are taken into account during transmission matrix formulation. As results indicate, for a 4×2 MIMO orientation (i.e. four transmit and two receive antennas) and six resolvable multipath components, the deployment of the proposed strategy can reduce up to 10% the mean number of repeats that are required for convergence of the transmission matrix calculation.
{"title":"A new transmission strategy for MIMO-WCDMA spatial multiplexing networks based on principal component analysis","authors":"P. Gkonis, D. Kaklamani, I. Venieris, C. Dervos, M. Chrysomallis","doi":"10.1109/LAPC.2015.7366105","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366105","url":null,"abstract":"The goal of the study presented in this paper is to investigate the performance of a new transmission strategy for MIMO-WCDMA networks operating in spatial multiplexing transmission mode, based on Principal Component Analysis (PCA) at the reception. In this context, all individual multipath components are first processed by a space - time RAKE receiver, and then PCA is employed on the received data matrix. The maximum eigenvalue along with the corresponding eigenvector are fed back to the transmitter, who formulates a modified correlation matrix. This matrix is used in order to determine the significant terms that are taken into account during transmission matrix formulation. As results indicate, for a 4×2 MIMO orientation (i.e. four transmit and two receive antennas) and six resolvable multipath components, the deployment of the proposed strategy can reduce up to 10% the mean number of repeats that are required for convergence of the transmission matrix calculation.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"161 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123367090","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366116
N. Rao, V. Dinesh Kumar
A novel Smith-Apollonian Gasket (SAG) fractal design for microstrip patch antenna is proposed in this paper. The proposed antenna design is a combination of Apollonian Gasket with Smith Chart. The SAG antenna has a multiband behavior in the frequency range from 3 GHz. to 10 GHz. The different frequencies generated from the different iterations can be used for different applications. Frequencies from 4th iteration are 4.5 GHz., 5.5 GHz., 7.5 Ghz. and 9.0 Ghz. The application of 4.5 GHz. is in Intelligent Transportation System (ITS) and Military Applications. The Application of 5.5 GHz is in WiMax and 7.5 GHz, 9.0 GHz. for satellite communication. The antenna has been designed on a substrate Roggers RO4003 lossy with εr=3.55 (dielectric constant) and loss tangent tanδ=0.0027.
{"title":"Multiband Smith-Apollonian Gasket fractal antenna for ITS, WiMAX, STM and satellite communication","authors":"N. Rao, V. Dinesh Kumar","doi":"10.1109/LAPC.2015.7366116","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366116","url":null,"abstract":"A novel Smith-Apollonian Gasket (SAG) fractal design for microstrip patch antenna is proposed in this paper. The proposed antenna design is a combination of Apollonian Gasket with Smith Chart. The SAG antenna has a multiband behavior in the frequency range from 3 GHz. to 10 GHz. The different frequencies generated from the different iterations can be used for different applications. Frequencies from 4th iteration are 4.5 GHz., 5.5 GHz., 7.5 Ghz. and 9.0 Ghz. The application of 4.5 GHz. is in Intelligent Transportation System (ITS) and Military Applications. The Application of 5.5 GHz is in WiMax and 7.5 GHz, 9.0 GHz. for satellite communication. The antenna has been designed on a substrate Roggers RO4003 lossy with εr=3.55 (dielectric constant) and loss tangent tanδ=0.0027.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"146 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124687509","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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