| 摘要 |
PROBLEM TO BE SOLVED: To provide an antenna device which handles a plurality of radio communication systems and can ensure high antenna performance with a small antenna area without requiring thickness.SOLUTION: An antenna device comprises: a first antenna element 11 whose length is an approximately half of a wavelength of a first operation frequency; a second antenna element 12 whose length is shorter than that of the first antenna element 11 by a predetermined length; a third antenna element 15 which surrounds the first and second antenna elements apart at predetermined intervals; a first power supply terminal and second power supply terminal 13 and 14 allocated to ends of the first and second antenna elements 11 and 12 ; and power supply terminals 16 and 17 allocated to both ends of a notch part of the third antenna element 15. A first antenna is configured by performing arrangement so that the first and second power supply terminals 13 and 14 are close to each other, and the first and second antenna elements 11 and 12 are orthogonal to each other. An antenna of a second operation frequency band is configured by arranging the third antenna element 15, which has an opening whose length is approximately double of a wavelength of a first operation frequency band and an outer periphery whose length is approximately one wavelength of a second operation frequency band, so as to be in parallel with the respective elements of the first antenna. |
