Comments on "Broadband Matching Limitations for Higher Order Spherical Modes

The authors of (Villalobos et al., 2009) believe that the analytical solution to the problem of matching for spherical mode TM₀₁ was first found in (Hujanen et al., 2005). In fact, that solution was found much earlier in (Kogan, 1980) where a new technique of solving the problem of broadband matching was proposed on the basis of the classic Schur´s method (Schur, 1917) applied to an interpolation problem for bounded functions analytical within a unit circle.