Directional switch antenna device

• US 20020105471A1
• Filed: 01/22/2002
• Published: 08/08/2002
• Est. Priority Date: 05/24/2000
• Status: Abandoned Application

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Enoki, Takashi, Kojima, Suguru
• Application Number:
  US10/031,460
• Publication Number:
  US 20020105471A1
• Time in Patent Office: Days
• US Class Current: 343/749
• CPC Class Codes: H01Q 19/32 the primary active element being end-fed and elongated
• CPC Class Codes: H01Q 3/24 varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching
• CPC Class Codes: H01Q 3/446 the radiating element being at the centre of one or more rings of auxiliary elements
• CPC Class Codes: H01Q 9/42 with folded element, the folded parts being spaced apart a small fraction of the operating wavelength

Abstract

A directionality switching antenna apparatus of the present invention is provided with radiator 102 in folded form, folded at a length of predetermined length from a feeding point of ground plane 101, with one end thereof connected to the feeding and with the other end thereof shorted with ground plane 101, a plurality of parasitic elements 103 spaced in the vicinity of radiator 102 each with an element length set to provide the parasitic elements with an electrically symmetrical relation to the center axis of radiator 102, inductors 104 loaded on respective parasitic elements 103, diodes 105 connected to ground plane 101, switching elements 106 that connects in parallel respective inductors 104 and respective diodes 105 between respective parasitic elements 103 and ground plane 101. In this way, even when positions of antenna elements become physically asymmetrical with respect to the axis of the radiator, the antenna elements are in electrically symmetrical relation, whereby it is possible to obtain equal radiation characteristics in each radiation direction.

Claims

1. A directionality switching antenna apparatus comprising:

a radiation element in folded form, folded at a length of predetermined wavelength from a feeding point of a ground plane, with one end thereof connected to the feeding point and with the other end thereof shorted with the ground plane;

a plurality of parasitic elements spaced in the vicinity of the radiation element, each having an element length set to provide the parasitic elements with an electrically symmetrical relation to the center axis of the radiation element and being loaded with one of inductive elements; and

a plurality of control circuits that switches on or off the function of one of the inductive elements.

8. A mobile station apparatus comprising the directionality switching antenna apparatus of claims 1.

9. A base station apparatus comprising the directionality switching antenna apparatus of claims 1.

2. A directionality switching antenna apparatus comprising:

a radiation element in folded form, folded at a length of predetermined wavelength from a feeding point of a ground plane, with one end thereof connected to the feeding point and with the other end thereof shorted with the ground plane;

a plurality of parasitic elements spaced in the vicinity of the radiation element, each having an element length set to provide the parasitic elements with an electrically symmetrical relation to the center axis of the radiation element and being loaded with one of capacitive element; and

a plurality of control circuits that switches on or off the function of one of the capacitive elements.

3. A directionality switching antenna apparatus comprising:

a radiation element in folded form, folded at a length of predetermined wavelength from a feeding point of a ground plane, with one end thereof connected to the feeding point and with the other end thereof shorted with the ground plane;

a plurality of parasitic elements spaced in the vicinity of the radiation element, each loaded with an inductive element set for a constant providing the parasitic elements with an electrically symmetrical relation to the center axis of the radiation element;

a plurality of control circuits that switches on or off the function of one of the inductive elements; and

a plurality of central constant circuits, each of which is connected to one of the control circuits, and is set for a constant providing the parasitic elements with the electrically symmetrical relation to the center axis of the radiation element.

4. A directionality switching antenna apparatus comprising:

a radiation element in folded form, folded at a length of predetermined wavelength from a feeding point of a ground plane, with one end thereof connected to the feeding point and with the other end thereof shorted with the ground plane;

a plurality of parasitic elements spaced in the vicinity of the radiation element, each loaded with a capacitive element set for a constant providing the parasitic elements with an electrically symmetrical relation to the center axis of the radiation element; and

a plurality of control circuits that switches on or off the function of one of the capacitive element; and

a plurality of central constant circuits, each of which is connected to the control circuits, and is set for a constant providing the parasitic elements with the electrically symmetric relation to the center axis of the radiation element.

5. A directionality switching antenna apparatus comprising:

a radiation element in folded form, folded at a length of predetermined wavelength from a feeding point of a ground plane, with one end thereof connected to the feeding point, with the other end thereof shorted with the ground plane, and with a portion rising from the feeding point folded so that the center of the antenna is positioned in the perpendicular direction at the feeding point;

a plurality of parasitic elements spaced in the vicinity of the radiation element;

a central constant circuit loaded on each of the parasitic elements;

a plurality of control circuits that switches on or off the function of one of the central constant elements.

6. A directionality switching antenna apparatus comprising:

a first radiation element in folded form, folded at a length of predetermined wavelength from a feeding point of a ground plane, with one end thereof connected to the feeding point, with the other end thereof shorted with the ground plane, and with a portion rising from the feeding point folded so that the center of the antenna is positioned in the perpendicular direction at the feeding point; and

a second radiation element in folded form, formed to be connected at the center of the first radiation element to the first radiation element.

7. A directionality switching antenna apparatus comprising:

a radiation element in folded form, with one end thereof connected to a feeding point of a ground plane, folded at a length of predetermined wavelength to have a plurality of branches with each end of the branches shorted with the ground plane, positions of the branches symmetrical with respect to the axis of a portion rising from the feeding point;

a plurality of parasitic elements spaced in the vicinity of the radiation element;

a central constant circuit loaded on each of the parasitic elements is loaded; and

a plurality of control circuits that switches on or off the function of one of the central constant circuits.