A numerical approach for automatic detection of the multipoles responsible for ill conditioning in generalized multipole technique

The generalized multipole technique in conjunction with the point matching technique has found its application in the electromagnetic field computation in case of radiating apertures. The conditioning of the resulting system of equation depends on the distribution of the multipoles inside the body of the antenna and matching points on the antenna surface and aperture. Although there are some empirical rules for distributing the multipoles to avoid ill conditioning, there is no systematic procedure to identify the multipoles responsible for the ill conditioning. In this contribution, we suggest a method to identify the multipoles, which are responsible for the ill conditioning and show the effect of eliminating these multipoles on the electromagnetic field computation.