| 摘要 |
A multiple frequency resonant antenna comprises a feed point Fd and a ground point Gd and a conductive track 12 extending between the said points. The conductive track 12 forms a first loop element and a second larger loop element, where the said loop elements include conductive track portions separated by a gap G and at least one shared conductive track portion H to Gd. The conductive track 12 is arranged with a small gap, containing dielectric material, from a parallel ground plane 2. The antenna may operate in a low frequency loop antenna mode and a high frequency patch antenna mode. The resonant frequencies of the antenna may be adjusted by changing various dimensions of the conductive track or possibly by changing the location of a shorting element 50 which can bridge the gap G and connect two portions of the track 12. In an alternative arrangement a first small U-shaped member, a large U-shaped member and a second small U-shaped member may be connected in series and the small U-shaped members may provide impedance matching for the antenna when it operates in a high frequency patch mode. The antenna provides a compact multi-frequency antenna for use in mobile telephones or radio transceiver devices. |
