The electromagnetic field that generated by line current and sheet current at the surface of the earth can be expressed in analytical form. The line current created at the earth’s surface by an infinitely long line c...The electromagnetic field that generated by line current and sheet current at the surface of the earth can be expressed in analytical form. The line current created at the earth’s surface by an infinitely long line current is given by the inverse Fourier integrals over a horizontal wave number. The sheet current can be obtained by integrating the line current expansions using a Neumann and Struve functions;these functions have known mathematical properties, including the series expansions. The series expansions are exact with neglecting the displacement currents. Assuming a uniform earth and that there is no propagation, the three nonzero field components can be expressed in terms of the Neumann and Struve functions. The integrals of line current expansions are calculated by using the numerical methods. The results represented graphically and illustrated by figures. Results can be used to evaluate numerical solutions of more complicated modeling algorithms.展开更多
A simple and explicit derivation for the electric and magnetic fields in the ferromagnetic cores has been studied. An improved model for analyzing the distribution of electric and magnetic fields in a toroidal core is...A simple and explicit derivation for the electric and magnetic fields in the ferromagnetic cores has been studied. An improved model for analyzing the distribution of electric and magnetic fields in a toroidal core is given. This leads to a basis system for the theoretical analysis of iron loss in the magnetic cores, so, the theoretical results have been evaluated. A method is used to perform numeric calculations of the magnetic field produced by the eddy current and displacement current due to the electric field which shield the magnetic flux from the inner portion of the core cross section. The results obtained from this work could be used to evaluate the skin effect in the conductors of a winding.展开更多
FMCW Radar (Frequency Modulated Continuous Wave Radar) is used for various purposes, such as atmospheric Remote Sensing, inter-vehicle ranging, etc. FMCW radar systems are usually very compact, relatively cheap in pur...FMCW Radar (Frequency Modulated Continuous Wave Radar) is used for various purposes, such as atmospheric Remote Sensing, inter-vehicle ranging, etc. FMCW radar systems are usually very compact, relatively cheap in purchase as well as in daily use, and consume little power. In this paper, FMCW radar determines a target range by measuring the beat frequency between a transmitted signal and the received signal from the target, and Combines between PO and radar single. The approach based on frequency domain physical optics for the scattering estimation and the linear system modeling for the estimation of time domain response, and FMCW Radar signal processing.展开更多
Rectangular reflector antennas have motivated the time-domain analysis of electromagnetic scattering problems. The asymptotic time domain physical-optics (TDPO) is applied to the analysis of a rectangular reflector il...Rectangular reflector antennas have motivated the time-domain analysis of electromagnetic scattering problems. The asymptotic time domain physical-optics (TDPO) is applied to the analysis of a rectangular reflector illuminated by a Gaussian-impulse. The effects of time-delayed mutual coupling between points on the surface will be ignored as a result of utilizing the TDPO method for determining the equivalent surface-current density on the reflector. Finally, in this work the scattered signals at the specular reflection point, at the edges, and at the corners can be clearly distinguished.展开更多
文摘The electromagnetic field that generated by line current and sheet current at the surface of the earth can be expressed in analytical form. The line current created at the earth’s surface by an infinitely long line current is given by the inverse Fourier integrals over a horizontal wave number. The sheet current can be obtained by integrating the line current expansions using a Neumann and Struve functions;these functions have known mathematical properties, including the series expansions. The series expansions are exact with neglecting the displacement currents. Assuming a uniform earth and that there is no propagation, the three nonzero field components can be expressed in terms of the Neumann and Struve functions. The integrals of line current expansions are calculated by using the numerical methods. The results represented graphically and illustrated by figures. Results can be used to evaluate numerical solutions of more complicated modeling algorithms.
文摘A simple and explicit derivation for the electric and magnetic fields in the ferromagnetic cores has been studied. An improved model for analyzing the distribution of electric and magnetic fields in a toroidal core is given. This leads to a basis system for the theoretical analysis of iron loss in the magnetic cores, so, the theoretical results have been evaluated. A method is used to perform numeric calculations of the magnetic field produced by the eddy current and displacement current due to the electric field which shield the magnetic flux from the inner portion of the core cross section. The results obtained from this work could be used to evaluate the skin effect in the conductors of a winding.
文摘FMCW Radar (Frequency Modulated Continuous Wave Radar) is used for various purposes, such as atmospheric Remote Sensing, inter-vehicle ranging, etc. FMCW radar systems are usually very compact, relatively cheap in purchase as well as in daily use, and consume little power. In this paper, FMCW radar determines a target range by measuring the beat frequency between a transmitted signal and the received signal from the target, and Combines between PO and radar single. The approach based on frequency domain physical optics for the scattering estimation and the linear system modeling for the estimation of time domain response, and FMCW Radar signal processing.
文摘Rectangular reflector antennas have motivated the time-domain analysis of electromagnetic scattering problems. The asymptotic time domain physical-optics (TDPO) is applied to the analysis of a rectangular reflector illuminated by a Gaussian-impulse. The effects of time-delayed mutual coupling between points on the surface will be ignored as a result of utilizing the TDPO method for determining the equivalent surface-current density on the reflector. Finally, in this work the scattered signals at the specular reflection point, at the edges, and at the corners can be clearly distinguished.
