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Time domain integral equation (TDIE) based solvers possess a number of advantages over other comp... more Time domain integral equation (TDIE) based solvers possess a number of advantages over other computational methods for the solution of wideband, nonlinear, and time-varying electromagnetic scattering and radiation phenomenon. Widespread use of TDIE solvers has been hindered by their historical inefficiency and instability. In the recent past, a new time marching method was proposed that used special bandlimited interpolation functions (BLIFs) for the temporal discretization of the TDIEs and a bandlimited extrapolation to create a causal scheme from these noncausal BLIFs, that overcame previous inaccuracy and instability issues. This paper presents an extension of this scheme to compute the scattering from inhomogeneous dielectric bodies using higher-order volume spatial basis functions. The results obtained from the new method show an excellent correspondence with those obtained from the standard, frequency domain method of moments

This work presents a stable and accurate method to solve the electromagnetic scattering from homo... more This work presents a stable and accurate method to solve the electromagnetic scattering from homogeneous dielectric scatterers using time domain integral equations (TDIE). In particular, it applies a loop-tree decomposition to the spatial testing functions and separately handles the solenoidal testing functions. For this purpose, the presented TDIE solver uses Rao-Wilton-Glisson (RWG) basis functions and bandlimited interpolatory functions (BLIF) to discretize the integral equations spatially and temporally, respectively, and implements a bandlimited extrapolation technique to overcome the noncausality introduced by the BLIF. Numerical results presented in this paper demonstrate the accuracy and stability of the method and illustrate the exponential convergence with respect to a temporal discretization parameter.

IEEE Transactions on Antennas and Propagation, 2004

Abstract—A new method to numerically solve time-domain integral equations pertinent to electromag... more Abstract—A new method to numerically solve time-domain integral equations pertinent to electromagnetic surface scattering phenomena is presented. The method uses approximate prolate spheroidal wave functions and standard Rao–Wilton–Glisson basis functions to effect the temporal ...

In recent years, the time domain integral equation based solvers for Maxwell's equations have bee... more In recent years, the time domain integral equation based solvers for Maxwell's equations have been gaining popularity. Although for certain types of problems they possess a number of advantages over other computational methods, their widespread usage has been hampered because of the instability and inefficiency encountered in early implementations. One new scheme that seems to overcome these instability problems is time marching using bandlimited extrapolation, which uses bandlimited basis functions for temporal representation, and bandlimited extrapolation to create a causal scheme from these noncausal basis functions. This paper presents an extension of this scheme to compute the scattering from homogeneous dielectric bodies. The results obtained from the new method show an excellent correspondence with those obtained from the standard, frequency domain method of moments.

IEEE Transactions on Antennas and Propagation, 2006

... Integral Equations Greeshma Pisharody, Student Member, IEEE, and Daniel S. Weile, Member, IEE... more ... Integral Equations Greeshma Pisharody, Student Member, IEEE, and Daniel S. Weile, Member, IEEE ... [16] MD Pocock, MJ Bluck, and SP Walker, “Electromagnetic scat-tering from 3-D curved dielectric bodies using time-domain integral equations,” IEEE Trans. ...

Microwave and Optical Technology Letters, 2005

A stabilization technique that overcomes the low-frequency instabilities encountered in current t... more A stabilization technique that overcomes the low-frequency instabilities encountered in current time-domain integral-equation implementations for electromagnetic-scattering problems is proposed. The approach augments the tangential-field integral equations with additional equations that impose the boundary condition on normal fields. The implementation uses the higher-order vector bases of Graglia et al. and bandlimited interpolation functions (BLIFs) to affect the spatial and temporal discretization of the integral equations, respectively. An extrapolation technique has been implemented to overcome the noncausality introduced by the BLIFs into the system. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 26–31, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20713

IEEE Transactions on Antennas and Propagation, 2004

Abstract—Despite the numerous advances made in increasing the computational efficiency of time-do... more Abstract—Despite the numerous advances made in increasing the computational efficiency of time-domain integral equation (TDIE)-based solvers, the stability and accuracy of TDIE solvers remain problematic. This paper introduces a new numerical method for the accurate ...

IEEE Transactions on Antennas and Propagation, 2005

... Extrapolation Greeshma Pisharody, Student, IEEE, and Daniel S. Weile, Member, IEEE ... 1064–1... more ... Extrapolation Greeshma Pisharody, Student, IEEE, and Daniel S. Weile, Member, IEEE ... 1064–1074, Jul. 2000. [22] MJ Bluck and SP Walker, “Time-domain BIE analysis of large three dimensional electromagnetic scattering problems,” IEEE Trans. Antennas Propag., vol. 45, no. ...

Time domain integral equation (TDIE) based solvers possess a number of advantages over other comp... more Time domain integral equation (TDIE) based solvers possess a number of advantages over other computational methods for the solution of wideband, nonlinear, and time-varying electromagnetic scattering and radiation phenomenon. Widespread use of TDIE solvers has been hindered by their historical inefficiency and instability. In the recent past, a new time marching method was proposed that used special bandlimited interpolation functions (BLIFs) for the temporal discretization of the TDIEs and a bandlimited extrapolation to create a causal scheme from these noncausal BLIFs, that overcame previous inaccuracy and instability issues. This paper presents an extension of this scheme to compute the scattering from inhomogeneous dielectric bodies using higher-order volume spatial basis functions. The results obtained from the new method show an excellent correspondence with those obtained from the standard, frequency domain method of moments

This work presents a stable and accurate method to solve the electromagnetic scattering from homo... more This work presents a stable and accurate method to solve the electromagnetic scattering from homogeneous dielectric scatterers using time domain integral equations (TDIE). In particular, it applies a loop-tree decomposition to the spatial testing functions and separately handles the solenoidal testing functions. For this purpose, the presented TDIE solver uses Rao-Wilton-Glisson (RWG) basis functions and bandlimited interpolatory functions (BLIF) to discretize the integral equations spatially and temporally, respectively, and implements a bandlimited extrapolation technique to overcome the noncausality introduced by the BLIF. Numerical results presented in this paper demonstrate the accuracy and stability of the method and illustrate the exponential convergence with respect to a temporal discretization parameter.

IEEE Transactions on Antennas and Propagation, 2004

Abstract—A new method to numerically solve time-domain integral equations pertinent to electromag... more Abstract—A new method to numerically solve time-domain integral equations pertinent to electromagnetic surface scattering phenomena is presented. The method uses approximate prolate spheroidal wave functions and standard Rao–Wilton–Glisson basis functions to effect the temporal ...

In recent years, the time domain integral equation based solvers for Maxwell's equations have bee... more In recent years, the time domain integral equation based solvers for Maxwell's equations have been gaining popularity. Although for certain types of problems they possess a number of advantages over other computational methods, their widespread usage has been hampered because of the instability and inefficiency encountered in early implementations. One new scheme that seems to overcome these instability problems is time marching using bandlimited extrapolation, which uses bandlimited basis functions for temporal representation, and bandlimited extrapolation to create a causal scheme from these noncausal basis functions. This paper presents an extension of this scheme to compute the scattering from homogeneous dielectric bodies. The results obtained from the new method show an excellent correspondence with those obtained from the standard, frequency domain method of moments.

IEEE Transactions on Antennas and Propagation, 2006

... Integral Equations Greeshma Pisharody, Student Member, IEEE, and Daniel S. Weile, Member, IEE... more ... Integral Equations Greeshma Pisharody, Student Member, IEEE, and Daniel S. Weile, Member, IEEE ... [16] MD Pocock, MJ Bluck, and SP Walker, “Electromagnetic scat-tering from 3-D curved dielectric bodies using time-domain integral equations,” IEEE Trans. ...

Microwave and Optical Technology Letters, 2005

A stabilization technique that overcomes the low-frequency instabilities encountered in current t... more A stabilization technique that overcomes the low-frequency instabilities encountered in current time-domain integral-equation implementations for electromagnetic-scattering problems is proposed. The approach augments the tangential-field integral equations with additional equations that impose the boundary condition on normal fields. The implementation uses the higher-order vector bases of Graglia et al. and bandlimited interpolation functions (BLIFs) to affect the spatial and temporal discretization of the integral equations, respectively. An extrapolation technique has been implemented to overcome the noncausality introduced by the BLIFs into the system. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 26–31, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20713

IEEE Transactions on Antennas and Propagation, 2004

Abstract—Despite the numerous advances made in increasing the computational efficiency of time-do... more Abstract—Despite the numerous advances made in increasing the computational efficiency of time-domain integral equation (TDIE)-based solvers, the stability and accuracy of TDIE solvers remain problematic. This paper introduces a new numerical method for the accurate ...

IEEE Transactions on Antennas and Propagation, 2005

... Extrapolation Greeshma Pisharody, Student, IEEE, and Daniel S. Weile, Member, IEEE ... 1064–1... more ... Extrapolation Greeshma Pisharody, Student, IEEE, and Daniel S. Weile, Member, IEEE ... 1064–1074, Jul. 2000. [22] MJ Bluck and SP Walker, “Time-domain BIE analysis of large three dimensional electromagnetic scattering problems,” IEEE Trans. Antennas Propag., vol. 45, no. ...