ADMITTANCE OF AN ISOLATED WAVE-GUIDE-FED SLOT RADIATING BETWEEN BAFFLES USING A SPECTRUM OF 2-DIMENSIONAL SOLUTIONS

This paper presents an efficient method of computing resonant length a nd admittance characteristics of an isolated broad-wall shunt slot, ra diating between baffles of finite height. The outer three-dimensional (3-D) field problem associated with this geometry is reduced to a two- dimensional (2-D) one via a Fourier transformation with respect to the longitudinal z direction. For each value of the longitudinal wave num ber k(z) an integral equation is solved for the E field in the mouth o f the plates using the method of moments. This procedure is repeated f or several discrete values of k(z), to obtain a spectrum of 2-D soluti ons which are then inverse-transformed to construct the 3-D solution i n the spatial domain for the exterior baffle region and the half space . The slot aperture field is determined by the conventional moment met hod solution to the integral equation that enforces the continuity of the H field across the slot. Scattering properties of the slot are the n deduced. Numerical results for the resonant length and resonant cond uctance are presented. Computed results are found to be in good agreem ent with experimentally measured data.