SYSTEMS AND METHODS FOR A CAPACITIVELY-LOADED LOOP ANTENNA

• US 20070222698A1
• Filed: 05/25/2007
• Published: 09/27/2007
• Est. Priority Date: 09/14/2004
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Ozkar, Mete, Fabrega-Sanchez, Jorge, Poilasne, Gregory, Pathak, Vaneet
• Granted Patent: US 7,760,151 B2
• Time in Patent Office: Days
• US Class Current: 343/866
• CPC Class Codes: H01Q 1/241 used in mobile communications, e.g. GSM H01Q1/247, H01Q1/248 take precedence
• CPC Class Codes: H01Q 21/29 Combinations of different interacting antenna units for giving a desired directional characteristic H01Q25/00 takes precedence
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop

Abstract

A capacitively-loaded loop antenna and corresponding radiation method have been provided. The antenna comprises a transformer loop having a balanced feed interface and a capacitively-loaded loop radiator. In one aspect, the capacitively-loaded loop radiator is a balanced radiator. In another, the transformed loop and capacitively-loaded loop radiator are physically connected. That is, the transformer loop and the capacitively-loaded loop radiator have a portion shared by both of the loop perimeters. Alternately, the loops are physically independent of each other. In one aspect, the perimeters have a rectangular shape. Other shapes such as round or oval are also possible. In another aspect, the planes formed by the transformer and capacitively-loaded loop radiator can be coplanar or non-planar, while both loops are orthogonal to a common magnetic near-field generated by the transformed loop. The radiator has a capacitively-loaded side, or capacitively loaded perimeter section, depending on the shape of the perimeter.

Claims

1. A wireless telephone communications device, the device comprising:

a telephone transceiver; and

,

a balanced feed capacitively-loaded loop antenna connected to the transceiver.

2. The device of claim 1 wherein the antenna includes:

a transformer loop having a balanced feed interface; and

,

a capacitively-loaded loop radiator.

3. The device of claim 2 wherein the capacitively-loaded loop radiator is a balanced radiator.

4. The device of claim 2 wherein the capacitively-loaded loop radiator includes:

a quasi loop with a first end section and a second end section; and

,

a bridge section interposed between the quasi loop first and second end sections.

5. The device of claim 4 wherein the bridge section is an element selected from the group including a dielectric gap capacitor and a lumped element capacitor.

6. The device of claim 5 wherein the transformer loop has a first perimeter;

and,

wherein the quasi loop has a second perimeter with at least a portion of the second perimeter in common with the first perimeter.

7. The device of claim 6 wherein the transformer loop has a rectangular shape with a first side;

and,

wherein the quasi loop has a rectangular shape with the first side.

8. The device of claim 4 wherein the transformer loop has a loop area in a first plane defined by a first perimeter, orthogonal to a first magnetic field;

and,

wherein the quasi loop has a loop area in a second plane, defined by a second perimeter, orthogonal to the first field.

9. The device of claim 8 wherein the transformer loop first perimeter is physically independent of the quasi loop second perimeter.

10. A wireless telephone communications base station with a capacitively-loaded loop antenna, the base station comprising:

a base station transceiver; and

,

a balanced feed capacitively-loaded loop antenna.

11. The base station of claim 10 wherein the antenna includes:

a transformer loop having a balanced feed interface; and

,

a capacitively-loaded loop radiator.

12. The base station of claim 11 wherein the capacitively-loaded loop radiator is a balanced radiator.

13. The base station of claim 11 wherein the capacitively-loaded loop radiator includes:

a quasi loop with a first end section and a second end section; and

,

a bridge section interposed between the quasi loop first and second end sections.

14. The base station of claim 13 wherein the bridge section is an element selected from the group including a dielectric gap capacitor and a lumped element capacitor.