Patent ID: 7256743
Filing Date: 2007-08-14
Classification: H01Q

Abstract:
1. An internal multiband antenna of a radio device, which antenna has at least a first and a second operating band and comprises a ground plane, a radiating plane and a radiating parasitic element electromagnetically coupled to the radiating plane, which radiating plane is at a feeding point connected to antenna port of the radio device and at a first short-circuit point to the ground plane, and is divided into a first and a second conductor branch as viewed from the first short-circuit point, and which parasitic element is at a second short-circuit point connected to the ground plane, wherein the first conductor branch together with the surrounding antenna parts forms a resonator having a natural frequency in said first operating band the second conductor branch together with the surrounding antenna parts forms a resonator having a natural frequency in said second operating band, and the parasitic element together with the surrounding antenna parts forms a resonator having a natural frequency in some operating band of the antenna, said feed point being close to the second short-circuit point, and the parasitic element being located substantially on the same geometric plane as the radiating plane, in its inner area.