| 摘要 |
PURPOSE:To obtain a small-sized antenna with a broad band buit in a portable radio equipment by constituting the antenna that an antenna element provided in parallel with an earthing plate is made flat and its end is grounded with a different width from both side faces. CONSTITUTION:The antenna element 1 formed flat which is made by cladding a conductor pattern on the front side and the rear side of a glass epoxy board, the earthing plate 4 and a short-circuit plate 2 for matching or the like made of a copper plate are formed into the incorporated structure. A part 2a stood upright of the matching short-circuit plate 2 to the earth plate 4 has an angle theta to the edge of the antenna element 1 and the antenna element 1 is grounded at points at distances of l1, l2 from the left end of the antenna element 1. The distances l1, l2 decide the upper and lower limit of the required frequency of the antenna. The position of a feeding point 3 is selected so that the relation of the l1 and l2 satisfies d1/d2 l1/l2. Thus, the desired antenna is con stituted. |
