| 摘要 |
<p>An antenna equipment for use with radio waves of a predetermined wavelength comprises a metal case (2; 112) for containing a radio circuit (3); a plastic case (1) surrounding and electrically insulating said metal case; and an antenna element for transmitting/receiving radio waves from/to the radio circuit, wherein said antenna element comprises a multilayered inductance element (7; 8; 17; 117) mounted externally of said metal case and formed of a plurality of sheets (FD) of insulating material stacked upon one another to form a stack, with conductor segments (PC) of a spirally shaped inductance element being carried separately on the sheets and being electrically connected to each other through via-holes (TH) extending through said sheets to form the multilayered inductance element in the form of a continuous conductor formed of the conductor segments and extending spirally within the stack of the sheets; and case or sleeve means (2; 11; 14; 15a, 15b; 112, 18) electromagnetically shielding said radio circuit (3) or parts (10) electrically connected to said radio circuit; wherein said multilayered inductance element (7; 17; 117) extends to an equivalent length equal to approximately a half of a wavelength, said multilayered inductance element acting with a matching circuit (9) and said case or sleeve means (2; 11; 14; 15a, 15b; 112, 18). <IMAGE></p> |
