Wave Propagation Governed by an Infinite Number of Transition Points

The reflection of waves from an isolated transition point isgeneralized to embrace an infinite number of evenly spaced non-isolatedtransition points lying on a straight line perpendicular tothe propagation axis in the complex plane. The comparison functionssuited to the problem are Bessel functions, yielding uniformapproximate solutions along the axis, from which reflectioncoefficients may be calculated. The theory is illustrated bycomparison with an exact analytical solution in terms of Whittakerfunctions, for a model containing two parallel lines of transitionpoints.