J. Kergomard et al., GENERAL FORMULATION OF WAVE-GUIDE JUNCTIO NS AT LOW-FREQUENCIES, Comptes rendus de l'Academie des sciences. Serie II. Mecanique, physique, chimie, astronomie, 319(8), 1994, pp. 887-892
A general expression for the low frequency impedance matrix for planar
modes of N-guides planar modes joined through a cavity is found. The
Green function decomposition of the cavity in terms of the eigenmodes
highlights the frequency dependence of the impedance. The Bernoulli ap
proximation of the impedance is deduced from the general expression.