A New Spatial Interpolation Algorithm to Reduce the Matrix Fill Time in the Method of Moments Analysis of Planar Microstrip Structures

A new spatial interpolation scheme is proposed to reduce the matrix fill time in the method of moments implementation of planar microstrip structures. The approach is based on the division of the distance between the basis and the testing functions into three, namely near, intermediate and far regions. The matrix entries in the near region are computed directly. The entries corresponding to both intermediate and far regions are evaluated in two steps: (1) choosing an adequate number of sampling points in these regions and computing the associated entries directly and (2) interpolating the remaining entries by using cubic spline or bicubic spline algorithms. To demonstrate the efficiency and accuracy, the technique is applied to a planar microstrip low-pass filter and a microstrip-line fed patch antenna problems. It is shown that the interpolation scheme can result in significant savings with high accuracy.

[1]  E. K. Miller,et al.  Application of the Cauchy method for extrapolating/interpolating narrowband system responses , 1997 .

[2]  E. Newman,et al.  Scattering from a microstrip patch , 1987 .

[3]  M. D. Deshpande,et al.  Fast RCS computation over a frequency band using method of moments in conjunction with asymptotic waveform evaluation technique , 1998 .

[4]  Lale Alatan,et al.  Analytical evaluation of the MoM matrix elements , 1996 .

[5]  Y. L. Chow,et al.  3-D Green's functions of microstrip separated into simpler terms-behavior, mutual interaction and formulas of the terms , 2001 .

[6]  Raj Mittra,et al.  An algorithm for interpolating the frequency variations of method-of-moments matrices arising in the analysis of planar microstrip structures , 2003 .

[7]  Gabriel F. Herrma Note on Interpolational Basis Functions in the Method of Moments , 1990 .

[8]  E. H. Newman,et al.  Generation of wide-band data from the method of moments by interpolating the impedance matrix (EM problems) , 1988 .

[9]  E. K. Miller,et al.  Accurate computation of wide-band response of electromagnetic systems utilizing narrow-band information , 1991 .

[10]  M. I. Aksun A robust approach for the derivation of closed-form Green's functions , 1996 .

[11]  Y. Lo,et al.  Theory and experiment on microstrip antennas , 1979 .

[12]  Y. Rahmat-Samii,et al.  Efficient wide-band evaluation of mobile communications antennas using [Z] or [Y] matrix interpolation with the method of moments , 1999 .

[13]  Ramachandra Achar,et al.  Simultaneous time and frequency domain solutions of EM problems using finite element and CFH techniques , 1996 .

[14]  E. K. Miller,et al.  Using model-based parameter estimation to increase the efficiency of computing electromagnetic transfer functions , 1989 .

[15]  D. M. Sheen,et al.  Application of the three-dimensional finite-difference time-domain method to the analysis of planar microstrip circuits , 1990 .

[16]  Raj Mittra,et al.  Parametric interpolation of the moment matrix in surface integral equation formulation , 1999 .

[17]  Steven C. Chapra,et al.  Numerical Methods for Engineers , 1986 .

[18]  G. F. Herrmann,et al.  Note on interpolational basis functions in the method of moments (EM scattering) , 1990 .

[19]  Bo Zhang,et al.  Efficient evaluation of the [Z] matrix with method of moment in grounding analysis by using adaptive spatial sampling approach , 2006, IEEE Transactions on Electromagnetic Compatibility.