A calderón multiplicative preconditioner for the combined field integral equation
KAUST DepartmentComputational Electromagnetics Laboratory
Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division
Electrical Engineering Program
Physical Science and Engineering (PSE) Division
Permanent link to this recordhttp://hdl.handle.net/10754/561446
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AbstractA Calderón multiplicative preconditioner (CMP) for the combined field integral equation (CFIE) is developed. Just like with previously proposed Caldern-preconditioned CFIEs, a localization procedure is employed to ensure that the equation is resonance-free. The iterative solution of the linear system of equations obtained via the CMP-based discretization of the CFIE converges rapidly regardless of the discretization density and the frequency of excitation. © 2009 IEEE.
SponsorsManuscript received October 17, 2008; revised January 27, 2009. First published August 07, 2009; current version published October 07, 2009. This work was supported in part by AFOSR MURI Grant F014432-051936, aimed at modeling installed antennas and their feeds, and by NSF Grant DMS 0713771.
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On the static loop modes in the marching-on-in-time solution of the time-domain electric field integral equationShi, Yifei; Bagci, Hakan; Lu, Mingyu (IEEE Antennas and Wireless Propagation Letters, Institute of Electrical and Electronics Engineers (IEEE), 2014) [Article]When marching-on-in-time (MOT) method is applied to solve the time-domain electric field integral equation, spurious internal resonant and static loop modes are always observed in the solution. The internal resonant modes have recently been studied by the authors; this letter investigates the static loop modes. Like internal resonant modes, static loop modes, in theory, should not be observed in the MOT solution since they do not satisfy the zero initial conditions; their appearance is attributed to numerical errors. It is discussed in this letter that the dependence of spurious static loop modes on numerical errors is substantially different from that of spurious internal resonant modes. More specifically, when Rao-Wilton-Glisson functions and Lagrange interpolation functions are used as spatial and temporal basis functions, respectively, errors due to space-time discretization have no discernible impact on spurious static loop modes. Numerical experiments indeed support this discussion and demonstrate that the numerical errors due to the approximate solution of the MOT matrix system have dominant impact on spurious static loop modes in the MOT solution. © 2014 IEEE.