Nonstationary excitation problem solution for a biconical structure consisting of an unclosed cone and isotropic one

The initial boundary value problem of building a nonstationary Green´s function of a perfectly conducting biconical surface consisting of a cone with periodical longitudinal slots and an isotropic one is considered. This geometry can be regarded as a model of a special biconical slot antenna with reflector, or a conical grating with a conical reflection screen. The solution method is based on using the Kontorovich-Lebedev integral transforms and the Rieman-Hilbert method. The analytical solution is derived for some particular cases of the structure