| 摘要 |
PROBLEM TO BE SOLVED: To provide an antenna device in which a proper placement pattern can be selected depending on the situation of the installation place of the antenna device while minimizing deterioration of antenna performance due to approach to the ground.SOLUTION: An antenna element 2 of an antenna device 1 includes a first antenna piece 4 having a feeding part 3 provided at one end, and a second antenna piece 5 formed by bending the other end of the first antenna piece 4 at a predetermined angle &thetas;. The antenna device 1 can select the placement of a pair of antenna elements 2, 2, by a first placement pattern where the angle formed by the second antenna pieces 5, 5 is about 180 degrees, and a second placement pattern where the angle formed by the second antenna pieces 5, 5 is about 90 degrees. In any one of the first or second placement pattern, the second antenna piece 5 is separated by a distance D, dependent on the length L of the first antenna piece 4 and the predetermined angle &thetas;, from a ground virtual line G determined with reference to one end of the first antenna piece 4. |
