An algorithm for interpolating the frequency variations of method-of-moments matrices arising in the analysis of planar microstrip structures

This paper presents a new impedance matrix interpolation algorithm, in the context of method of moments, for planar microstrip structures. Three different interpolating functions are implemented depending upon the distance between the basis and testing functions. To demonstrate its efficiency, the technique is applied to several planar microstrip structures, viz. a patch antenna fed by microstrip line and a 4×4 planar patch array. It is demonstrated that the use of the proposed impedance matrix interpolation scheme can result in significant savings in the computation time with little or no compromise in the accuracy of the solution.