| 摘要 |
An antenna comprises an insulating substrate 403 with first and second conductive portions 501, 502 on opposite respective surfaces of the said substrate. The first said portion 501 provides a first quarter wavelength resonator for frequencies in the range of 800 MHz to 1000 MHz and the second said portion 502 provides a second quarter wavelength resonator for frequencies in the range of 1200 MHz to 2000 MHz. The said first and second radiators 501, 502 have no direct galvanic connection. The substrate 403 also carries a ground plane portion 509. The substrate 403 is separated and supported by insulating support columns 405 from a conducting support member 301 which provides at least part of a ground plane. The conducting support member 301 may be electrically connected via a conductive shorting pin 411 to the ground plane portion 509 and the second conducting portion 502. The central conductor 505 of a coaxial cable 409 may be soldered to the first radiator so that it can supply a feed signal to the said first radiator 501. The outer conductor 508 of the coaxial cable 409 may supply a feed signal to the second radiator 502 via the third conducting portion 509 and conductive via elements 511. Other conductive elements associated with an imager device may be used to improve the impedance matching of the antenna elements. The compact, efficient multi-frequency antenna may be suitable for use in a wireless communication device. |
