Patent ID: 6163307
Filing Date: 2000-12-19
Classification: H01Q

Abstract:
A multilayered helical antenna for use in mobile communication units comprising:a first dielectric sheet provided with a through-hole at a center thereof;a plurality of second dielectric sheets, all of the second dielectric sheets, except one, being provided with a starting hole and an ending hole, the exception is the first one of second dielectric sheets having only one starting hole, each being provided with a partially opened circular metallic pattern and a through-hole at a center thereof, wherein the partially opened circular metallic pattern extends from the starting hole to the ending hole in the respective second dielectric sheet except for the dielectric sheet having the starting hole only where the partially opened circular metallic pattern extends from the starting hole to a free end; anda plurality of third dielectric sheets, each being provided with a via hole and a through-hole at a center thereof, wherein the dielectric sheets are stacked in a predetermined order, the order being that the first dielectric sheet is placed at top of the stack followed by the second dielectric sheet with the starting hole only followed by the third dielectric sheet followed by the second dielectric sheet followed by the third dielectric sheet and so on, with the third dielectric sheet being placed at bottom of the stack, the via holes being filled with a conducting material to thereby vertically connect the partially opened circular metallic patterns on the second dielectric sheets through the corresponding starting holes and ending holes, forming a spiral inside the stack of dielectric sheets, thereby forming a helical antenna, and the through-holes therein being used to allow a whip antenna to be slid upward and downward along a center axis of the helical antenna to thereby form said multilayered helical antenna.