ABSTRACTWith development of novel technologies, radio frequency (RF) energy exposure is expanding... more ABSTRACTWith development of novel technologies, radio frequency (RF) energy exposure is expanding at various wavelengths and power levels. These developments necessitate updated approaches of RF measurements in complex environments, particularly in live biological tissue. In this study, we introduce a technique for direct in-vivo measurement of electric fields in living tissue. Proof of principle in-vivo electric field measurements were conducted in rodent brains using Bismuth Silicon Oxide (BSO) crystals exposed to varying levels of RF energy. Electric field measurements were calibrated and verified using in-vivo temperature measurements using optical temperature fibers alongside electromagnetic field simulations of a transverse electromagnetic (TEM) cell.SIGNIFICANCEAccurate dosimetry of the absorbed radio frequency (RF) electric fields (E-Fields) by the live tissue is the keystone of environmental health considerations for this type of ever-growing non-ionizing radiation energy. ...
2021 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting (APS/URSI), 2021
In this paper, we describe a hybrid parallel FDTD solver for simulation of large-scale urban prop... more In this paper, we describe a hybrid parallel FDTD solver for simulation of large-scale urban propagation scenarios that utilizes both shared and distributed memory capabilities of modern processors. Simulation results are presented for an accurate real-world physical urban model (Downtown Los Angeles) at HF band (40 MHz).
IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010)
Page 1. EFFICIENT PRINTED ANTENNA ARRAY SYNTHESIS INCLUDING COUPLING EFFECTS USING EVOLUTIONARY G... more Page 1. EFFICIENT PRINTED ANTENNA ARRAY SYNTHESIS INCLUDING COUPLING EFFECTS USING EVOLUTIONARY GENETIC ALGORITHMS Kazem F. %bet*', Dennis P. Jones', Jui-Ching Cheng', Linda PB Katehi", Kamd ...
IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010)
Page 1. AN ACCELERATED HYBRID GENETIC ALGORITHM FOR OPTIMIZATOIN OF ELECTROMAGNETIC STRUCTURES De... more Page 1. AN ACCELERATED HYBRID GENETIC ALGORITHM FOR OPTIMIZATOIN OF ELECTROMAGNETIC STRUCTURES Dennis P. Jones', Kazem F. SabeP', Jui-Ching Cheng', Linda PB Katehi", Karnal Sarabandi*$ and ...
A recent technique for the analysis of open dielectric guiding structures has introduced a spectr... more A recent technique for the analysis of open dielectric guiding structures has introduced a spectral-domain integral equation, in which the unknown function does not have a compact support but is square-integrable over the entire real line. To solve this integral equation by the method of moments, a quasi-wavelet Hermite-Gaussian expansion is proposed as an entire-domain basis, and some of its properties are discussed. It is shown that a small number of these entire-domain basis functions can provide quite fast numerical convergence
A general spectral-domain technique is developed which reduces the dimensionality of the space-do... more A general spectral-domain technique is developed which reduces the dimensionality of the space-domain integral equation for a large class of open dielectric waveguides. This technique has the merit of easy extension to three-dimensional structures. As an example, a simple rectangular slab guide is considered, and the corresponding spectral-domain modified Green's function is derived. To solve the resulting equations, the method of moments is employed in the spectral domain using entire-domain Hermite-Gaussian functions. The results show good agreement with other methods, and only a few basis functions are needed to achieve quick convergence.
It was shown that the use of orthonormal wavelets in the numerical solution of certain integral e... more It was shown that the use of orthonormal wavelets in the numerical solution of certain integral equations leads to sparsely populated matrices. This idea was employed in the moment method formulation of electromagnetic scattering problems, where a specific example of a double-slot aperture in a planar conducting screen is presented using Battle-Lemarie wavelets. A concern in the application of wavelet expansions to electromagnetic problems is the restoration of the DC or lowpass part of the fields. We show how to make this provision by a systematic use of the multiresolution analysis theory. In this way, the number of expansion functions can also be reduced to a minimum. It is believed that using wavelets with a large number of vanishing moments leads to an increase in the sparsity of the matrices. This issue is examined by a discussion of orthonormal wavelets with both infinite and compact supports. Numerical results are presented for the case of an open dielectric strip waveguide
ABSTRACTWith development of novel technologies, radio frequency (RF) energy exposure is expanding... more ABSTRACTWith development of novel technologies, radio frequency (RF) energy exposure is expanding at various wavelengths and power levels. These developments necessitate updated approaches of RF measurements in complex environments, particularly in live biological tissue. In this study, we introduce a technique for direct in-vivo measurement of electric fields in living tissue. Proof of principle in-vivo electric field measurements were conducted in rodent brains using Bismuth Silicon Oxide (BSO) crystals exposed to varying levels of RF energy. Electric field measurements were calibrated and verified using in-vivo temperature measurements using optical temperature fibers alongside electromagnetic field simulations of a transverse electromagnetic (TEM) cell.SIGNIFICANCEAccurate dosimetry of the absorbed radio frequency (RF) electric fields (E-Fields) by the live tissue is the keystone of environmental health considerations for this type of ever-growing non-ionizing radiation energy. ...
2021 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting (APS/URSI), 2021
In this paper, we describe a hybrid parallel FDTD solver for simulation of large-scale urban prop... more In this paper, we describe a hybrid parallel FDTD solver for simulation of large-scale urban propagation scenarios that utilizes both shared and distributed memory capabilities of modern processors. Simulation results are presented for an accurate real-world physical urban model (Downtown Los Angeles) at HF band (40 MHz).
IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010)
Page 1. EFFICIENT PRINTED ANTENNA ARRAY SYNTHESIS INCLUDING COUPLING EFFECTS USING EVOLUTIONARY G... more Page 1. EFFICIENT PRINTED ANTENNA ARRAY SYNTHESIS INCLUDING COUPLING EFFECTS USING EVOLUTIONARY GENETIC ALGORITHMS Kazem F. %bet*', Dennis P. Jones', Jui-Ching Cheng', Linda PB Katehi", Kamd ...
IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010)
Page 1. AN ACCELERATED HYBRID GENETIC ALGORITHM FOR OPTIMIZATOIN OF ELECTROMAGNETIC STRUCTURES De... more Page 1. AN ACCELERATED HYBRID GENETIC ALGORITHM FOR OPTIMIZATOIN OF ELECTROMAGNETIC STRUCTURES Dennis P. Jones', Kazem F. SabeP', Jui-Ching Cheng', Linda PB Katehi", Karnal Sarabandi*$ and ...
A recent technique for the analysis of open dielectric guiding structures has introduced a spectr... more A recent technique for the analysis of open dielectric guiding structures has introduced a spectral-domain integral equation, in which the unknown function does not have a compact support but is square-integrable over the entire real line. To solve this integral equation by the method of moments, a quasi-wavelet Hermite-Gaussian expansion is proposed as an entire-domain basis, and some of its properties are discussed. It is shown that a small number of these entire-domain basis functions can provide quite fast numerical convergence
A general spectral-domain technique is developed which reduces the dimensionality of the space-do... more A general spectral-domain technique is developed which reduces the dimensionality of the space-domain integral equation for a large class of open dielectric waveguides. This technique has the merit of easy extension to three-dimensional structures. As an example, a simple rectangular slab guide is considered, and the corresponding spectral-domain modified Green's function is derived. To solve the resulting equations, the method of moments is employed in the spectral domain using entire-domain Hermite-Gaussian functions. The results show good agreement with other methods, and only a few basis functions are needed to achieve quick convergence.
It was shown that the use of orthonormal wavelets in the numerical solution of certain integral e... more It was shown that the use of orthonormal wavelets in the numerical solution of certain integral equations leads to sparsely populated matrices. This idea was employed in the moment method formulation of electromagnetic scattering problems, where a specific example of a double-slot aperture in a planar conducting screen is presented using Battle-Lemarie wavelets. A concern in the application of wavelet expansions to electromagnetic problems is the restoration of the DC or lowpass part of the fields. We show how to make this provision by a systematic use of the multiresolution analysis theory. In this way, the number of expansion functions can also be reduced to a minimum. It is believed that using wavelets with a large number of vanishing moments leads to an increase in the sparsity of the matrices. This issue is examined by a discussion of orthonormal wavelets with both infinite and compact supports. Numerical results are presented for the case of an open dielectric strip waveguide
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