ANTENNA

PROBLEM TO BE SOLVED: To provide a transmitting or receiving antenna achieving high-level frequency directivity characteristics in microwave ranges. SOLUTION: The antenna contains at least one probes 10, which can convert electrical energy into electromagnetic energy and vice versa, and an assembly 20 of elements made of at least two materials of different dielectric constants and/or magnetic permeability and/or electrical conductivity. Within it, the probes are located, an arrangement of the elements in the assembly ensures radiation and spatial frequency filtering of the electromagnetic waves generated or received with the probes; and through the filtering, an operating frequency f, required to be transmitted for one or more antennas within a gap particularly in a certain non-transmission frequency band, is permitted. In addition, the assembly 20 of the elements has radial form periodicity, and at least one cavity 21 in the radial form periodicity. COPYRIGHT: (C)2004,JPO