Coupling Matrix Extraction by Entries Deviation and with Use of Sherman-Morrison Formula

This paper presents a new method of coupling matrix extraction. In this method it is assumed that we have scattering or admittance parameters at single frequency point for each entries of coupling matrix deviated by any of two different values from the proper value. By using Sherman-Morrison matrix formula for the elements of inverse coupling matrix and corresponding scattering or admittance values it is possible to obtain one by one all entries of the entire inverse matrix to the coupling matrix. Finally by inverse of resulting matrix the extracted coupling matrix is obtained. Additionally it is shown that the coupling matrix can be fully extracted using of one scattering parameter only, i.e. reflection or transmission, assuming that all coupling matrix entries are deviated including those equal to zero. Numerical experiment presented in the paper proved the correctness of the proposed approach.