NON-DIRECTIONAL ANTENNA

PROBLEM TO BE SOLVED: To provide a non-directional antenna by which displacement of the position in the maximum radiation direction of vertical in-plane directivity can be prevented and the level deviation of horizonal in-plane directivity can be suppressed. SOLUTION: The non-directional antenna includes first and second dipole antenna elements (10A and 10B) which are arranged above and below with a specified spacing in such a manner that their central axis lines in the direction of length are positioned on a plumb line, a bifurcated feeder (30) which is arranged along the first and second dipole antenna elements (10A and 10B) and one end and the other end of which are connected with the first and second dipole antenna elements (10A and 10B) respectively and a main electric supply line (40) which is connected with the bifurcated feeder (30), passes through between the first and second antenna elements (10A and 10B) and then is led downward along the second antenna element (10B). The portion of the main electric supply line (40) which is led downward and the bi-distribution electric line (30) are positioned approximately symmetrically with respect to the second dipole antenna element (10B). COPYRIGHT: (C)2007,JPO&INPIT