Comparison of Specific Absorption Rate (SAR) Induced in Child- ... Sized and Adult Heads Using a ... more Comparison of Specific Absorption Rate (SAR) Induced in Child- ... Sized and Adult Heads Using a Dual Band Mobile Phone ... Abdelhamid Hadjem*, David Lautru**, Member, IEEE, Christian Dale*, Man Fa? Wong*, Senior Member, IEEE, Victor Fouad Hanna**, Fellow, IEEE, Joe ...
IEEE Antennas and Propagation Society International Symposium. Transmitting Waves of Progress to the Next Millennium. 2000 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.00CH37118), 2000
A method of moments in the time domain/finite difference time domain (MoMTD/FDTD) hybrid method h... more A method of moments in the time domain/finite difference time domain (MoMTD/FDTD) hybrid method has been used to calculate the radiation of a helix antenna and validated. A solution has been suggested for the problem of materials crossing at the interface between the two methods. The results are stable, but the accuracy still needs to be improved. The calculation of
2011 XXXth URSI General Assembly and Scientific Symposium, 2011
ar-field induced by a cellular phone in a human hea is technique is first based on Huygens princi... more ar-field induced by a cellular phone in a human hea is technique is first based on Huygens principle usin r any cellular phone. Then, using Singular Value Dec would be expanded with the orthonormalized modes lly, we estimate the error reconstruction of E-field u
IEEE MTT-S International Microwave Symposium Digest, 2005., 2005
Abdelhamid Hadjem 1, David Lautru 2, Member, IEEE, Najib Gadi 3, Isabelle Bloch 3, Christian Dale... more Abdelhamid Hadjem 1, David Lautru 2, Member, IEEE, Najib Gadi 3, Isabelle Bloch 3, Christian Dale 1, Man Faï Wong 1, Senior Member, IEEE, Victor Fouad Hanna 2, Fellow, IEEE, Joe Wiart 1, Senior Member, IEEE ... 1 France Télécom, Division R&D, RESA/FACE, 38-40 rue du ...
A simulation based on the hybridization of the FDTD (Finite Difference Time Domain) and the MoMTD... more A simulation based on the hybridization of the FDTD (Finite Difference Time Domain) and the MoMTD (Moments Method in the Time Domain) has been used to compute the power absorbed by a person placed in the near field zone of a BSA (Base Station antenna). This numerical simulation uses a hybridization based on the equivalence theorem. Comparisons of the technique
IEEE MTT-S International Microwave Symposium Digest, 2003, 2003
Abstract - This paper presents B study of Specific Absorption Rate (SAR) induced in the head of a... more Abstract - This paper presents B study of Specific Absorption Rate (SAR) induced in the head of a person wearing protection garment without hood. Electromagnetic fields in the head are determined using a combination of the Finite Difference in Time Domain (FDTD) method ...
In this paper, the general public daily exposure to radiofrequencies in indoor areas is investiga... more In this paper, the general public daily exposure to radiofrequencies in indoor areas is investigated. The considered signals are FM, TV, and GSM over one day. The study focus on the determination of the distribution of FM, TV, and GSM signals in a realistic electromagnetic environment in Indoor distinguishing Urban and Rural locations. The goal is to analyze the real
2012 IEEE Topical Conference on Biomedical Wireless Technologies, Networks, and Sensing Systems (BioWireleSS), 2012
This paper presents results for the Specific Absorption Rate (SAR) when using a mobile phone equi... more This paper presents results for the Specific Absorption Rate (SAR) when using a mobile phone equipped with a multiple antenna system. The SAR is evaluated using the Finite Difference Time Domain (FDTD) method for different configurations taking into account all possible simultaneous transmission from a mobile phone. The considered signals are GSM900, GSM1800, UMTS2100 and WiFi2400. The results show that
2006 European Conference on Wireless Technologies, 2006
This paper presents a new approach which allows to decrease the computation volume and the simula... more This paper presents a new approach which allows to decrease the computation volume and the simulation time in dosimetric problems. This method uses a larger segmentation for the electric field calculation and an appropriate technique to assess the specific absorption rate (SAR) induced into biological structures. To validate this approach, a 1D multilayer structure is exposed to a plane wave
IEEE Microwave and Wireless Components Letters, 2009
In this letter, the uncertainties on the angles of propagation of a plane wave in a bio electroma... more In this letter, the uncertainties on the angles of propagation of a plane wave in a bio electromagnetic application are studied using two non intrusive stochastic collocation methods. The proposed techniques are used in this application, which employs a finite-difference time-domain scheme, but they can be used when applying other kinds of methods without modifying programs. The results obtained using
2011 6th International Conference on Design & Technology of Integrated Systems in Nanoscale Era (DTIS), 2011
Abstract An abdominal aortic aneurysm (AAA) is a dilatation of the aorta at the abdominal level, ... more Abstract An abdominal aortic aneurysm (AAA) is a dilatation of the aorta at the abdominal level, the rupture of which is a life threatening complication with an 80% mortality rate. Even though those devices keep improving, the failure rate of the endovascular treatment is due ...
Time reversal technique is demonstrated to be a promising efficient technique for use in wireless... more Time reversal technique is demonstrated to be a promising efficient technique for use in wireless communications applications. Benefiting from multi-paths wave propagation, the time reversal technique has the unique feature to focus a signal in both space and time. This paper investigates two factors influencing the space-time focusing in a reverberation chamber when using time reversal technique associated with the
In this paper, a technique allowing to model any orientation of a thin wire antenna in a fdtd mes... more In this paper, a technique allowing to model any orientation of a thin wire antenna in a fdtd mesh is presented. This approach is based on a hybridization between the fdtd (Finite Difference Time Domain) method and the momtd (Method of Moments in the Time Domain). A comparison between a near field-to-near field transformation and an interpolation method to transmit
IEEE Transactions on Microwave Theory and Techniques, 2000
... AbstractThis paper gives a first comparison of specific absorp-tion rate (SAR) induced in a ... more ... AbstractThis paper gives a first comparison of specific absorp-tion rate (SAR) induced in a child-sized (CS) head and an adult head using a dual-band mobile phone. ... Today, the mobile phone, in particular, is used by millions of users, including children. ...
annals of telecommunications - annales des télécommunications, 2008
Page 1. ORIGINAL PAPER Evaluation of the SAR induced in a multilayer biological structure and com... more Page 1. ORIGINAL PAPER Evaluation of the SAR induced in a multilayer biological structure and comparison with SAR in homogeneous tissues Aline Pradier & Abdelhamid Hadjem & David Lautru & Azeddine Gati & Man-Faï Wong & Victor Fouad Hanna & Joe Wiart ...
Comparison of Specific Absorption Rate (SAR) Induced in Child- ... Sized and Adult Heads Using a ... more Comparison of Specific Absorption Rate (SAR) Induced in Child- ... Sized and Adult Heads Using a Dual Band Mobile Phone ... Abdelhamid Hadjem*, David Lautru**, Member, IEEE, Christian Dale*, Man Fa? Wong*, Senior Member, IEEE, Victor Fouad Hanna**, Fellow, IEEE, Joe ...
IEEE Antennas and Propagation Society International Symposium. Transmitting Waves of Progress to the Next Millennium. 2000 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.00CH37118), 2000
A method of moments in the time domain/finite difference time domain (MoMTD/FDTD) hybrid method h... more A method of moments in the time domain/finite difference time domain (MoMTD/FDTD) hybrid method has been used to calculate the radiation of a helix antenna and validated. A solution has been suggested for the problem of materials crossing at the interface between the two methods. The results are stable, but the accuracy still needs to be improved. The calculation of
2011 XXXth URSI General Assembly and Scientific Symposium, 2011
ar-field induced by a cellular phone in a human hea is technique is first based on Huygens princi... more ar-field induced by a cellular phone in a human hea is technique is first based on Huygens principle usin r any cellular phone. Then, using Singular Value Dec would be expanded with the orthonormalized modes lly, we estimate the error reconstruction of E-field u
IEEE MTT-S International Microwave Symposium Digest, 2005., 2005
Abdelhamid Hadjem 1, David Lautru 2, Member, IEEE, Najib Gadi 3, Isabelle Bloch 3, Christian Dale... more Abdelhamid Hadjem 1, David Lautru 2, Member, IEEE, Najib Gadi 3, Isabelle Bloch 3, Christian Dale 1, Man Faï Wong 1, Senior Member, IEEE, Victor Fouad Hanna 2, Fellow, IEEE, Joe Wiart 1, Senior Member, IEEE ... 1 France Télécom, Division R&D, RESA/FACE, 38-40 rue du ...
A simulation based on the hybridization of the FDTD (Finite Difference Time Domain) and the MoMTD... more A simulation based on the hybridization of the FDTD (Finite Difference Time Domain) and the MoMTD (Moments Method in the Time Domain) has been used to compute the power absorbed by a person placed in the near field zone of a BSA (Base Station antenna). This numerical simulation uses a hybridization based on the equivalence theorem. Comparisons of the technique
IEEE MTT-S International Microwave Symposium Digest, 2003, 2003
Abstract - This paper presents B study of Specific Absorption Rate (SAR) induced in the head of a... more Abstract - This paper presents B study of Specific Absorption Rate (SAR) induced in the head of a person wearing protection garment without hood. Electromagnetic fields in the head are determined using a combination of the Finite Difference in Time Domain (FDTD) method ...
In this paper, the general public daily exposure to radiofrequencies in indoor areas is investiga... more In this paper, the general public daily exposure to radiofrequencies in indoor areas is investigated. The considered signals are FM, TV, and GSM over one day. The study focus on the determination of the distribution of FM, TV, and GSM signals in a realistic electromagnetic environment in Indoor distinguishing Urban and Rural locations. The goal is to analyze the real
2012 IEEE Topical Conference on Biomedical Wireless Technologies, Networks, and Sensing Systems (BioWireleSS), 2012
This paper presents results for the Specific Absorption Rate (SAR) when using a mobile phone equi... more This paper presents results for the Specific Absorption Rate (SAR) when using a mobile phone equipped with a multiple antenna system. The SAR is evaluated using the Finite Difference Time Domain (FDTD) method for different configurations taking into account all possible simultaneous transmission from a mobile phone. The considered signals are GSM900, GSM1800, UMTS2100 and WiFi2400. The results show that
2006 European Conference on Wireless Technologies, 2006
This paper presents a new approach which allows to decrease the computation volume and the simula... more This paper presents a new approach which allows to decrease the computation volume and the simulation time in dosimetric problems. This method uses a larger segmentation for the electric field calculation and an appropriate technique to assess the specific absorption rate (SAR) induced into biological structures. To validate this approach, a 1D multilayer structure is exposed to a plane wave
IEEE Microwave and Wireless Components Letters, 2009
In this letter, the uncertainties on the angles of propagation of a plane wave in a bio electroma... more In this letter, the uncertainties on the angles of propagation of a plane wave in a bio electromagnetic application are studied using two non intrusive stochastic collocation methods. The proposed techniques are used in this application, which employs a finite-difference time-domain scheme, but they can be used when applying other kinds of methods without modifying programs. The results obtained using
2011 6th International Conference on Design & Technology of Integrated Systems in Nanoscale Era (DTIS), 2011
Abstract An abdominal aortic aneurysm (AAA) is a dilatation of the aorta at the abdominal level, ... more Abstract An abdominal aortic aneurysm (AAA) is a dilatation of the aorta at the abdominal level, the rupture of which is a life threatening complication with an 80% mortality rate. Even though those devices keep improving, the failure rate of the endovascular treatment is due ...
Time reversal technique is demonstrated to be a promising efficient technique for use in wireless... more Time reversal technique is demonstrated to be a promising efficient technique for use in wireless communications applications. Benefiting from multi-paths wave propagation, the time reversal technique has the unique feature to focus a signal in both space and time. This paper investigates two factors influencing the space-time focusing in a reverberation chamber when using time reversal technique associated with the
In this paper, a technique allowing to model any orientation of a thin wire antenna in a fdtd mes... more In this paper, a technique allowing to model any orientation of a thin wire antenna in a fdtd mesh is presented. This approach is based on a hybridization between the fdtd (Finite Difference Time Domain) method and the momtd (Method of Moments in the Time Domain). A comparison between a near field-to-near field transformation and an interpolation method to transmit
IEEE Transactions on Microwave Theory and Techniques, 2000
... AbstractThis paper gives a first comparison of specific absorp-tion rate (SAR) induced in a ... more ... AbstractThis paper gives a first comparison of specific absorp-tion rate (SAR) induced in a child-sized (CS) head and an adult head using a dual-band mobile phone. ... Today, the mobile phone, in particular, is used by millions of users, including children. ...
annals of telecommunications - annales des télécommunications, 2008
Page 1. ORIGINAL PAPER Evaluation of the SAR induced in a multilayer biological structure and com... more Page 1. ORIGINAL PAPER Evaluation of the SAR induced in a multilayer biological structure and comparison with SAR in homogeneous tissues Aline Pradier & Abdelhamid Hadjem & David Lautru & Azeddine Gati & Man-Faï Wong & Victor Fouad Hanna & Joe Wiart ...
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