| 摘要 |
PROBLEM TO BE SOLVED: To provide an antenna system that is operable even at a low wavelength band of several GHz with a size nearly the same as that of an nondirectional antenna system and whose directivity can be varied. SOLUTION: The antenna system 21 is provided with: a coaxial line 22 comprising a radiator (radiation element), and a ground conductor 31 continuously provided on the radiator 23 and concentrically provided in the outer part of a signal line 30 around the signal line 30 for feeding the radiator 23; and a ground disk plate 24 provided in a border part between the coaxial line 22 and the radiator 23. Then the ground plate 24 has a dielectric film 28 formed thereon, and short-circuit lines (electric field changing means) 27a to 27d changing the electric field distribution of the coaxial line 22 and bias lines (conductor members) 25a to 25d connected to the short-circuit lines 27a to 27d are formed on the dielectric film 28, and switches 26a to 26d for interrupting the connections between the bias lines 25a to 25d and the short-circuit lines 27a to 27d are arranged. COPYRIGHT: (C)2005,JPO&NCIPI
|
