Antenna structure and electronic device having same

Patent metadata

Field	Value
Publication number	US-9912049-B2
Application number	US-201414527127-A
Country	US
Kind code	B2
Filing date	Oct 29, 2014
Priority date	Oct 15, 2014
Publication date	Mar 6, 2018
Grant date	Mar 6, 2018

Abstract

A dual-band Wi-Fi antenna structure includes a metallic middle frame of a casing of a handheld electronic device, a grounding plane received in the middle frame, an antenna body connected to the grounding plane, and an adjusting element. The grounding plane defines a rectangular recess in a corner thereof. The antenna body has a radiation patch having a part located over the recess. The adjusting element is located in the recess. An effective length of the recess is adjustable by adjusting a parameter of the adjusting element, which is a coefficient of self-inductance when the adjusting element is an adjustable inductor. By adjusting the effective length of the recess, a resonant frequency of the antenna structure at a low frequency band is adjustable, while a resonant frequency thereof at a high frequency band is not altered.

First claim

What is claimed is:

1. An electronic device with a dual-band antenna structure comprising:
a metallic middle frame, the metallic middle frame including a first side wall and a second side wall connected to, and substantially perpendicular to, the first side wall;
a grounding plane configured to be received into the middle frame, the grounding plane having:
a first side edge, having a first portion and a second portion;
a second side edge substantially perpendicular to both the first portion and second portion of the first side edge; and
a first face substantially perpendicular to the first side edge and to the second side edge;

wherein, when the grounding plane is received into the middle frame:
the first portion and second portion of the first side edge are substantially parallel to the first side wall and the second portion of the first side edge is substantially adjacent the first side wall; and
the second edge of the grounding plane is substantially parallel to the second side wall and positioned substantially near the second side wall; and
wherein, the first portion of the first side edge, the first side wall and the second side wall cooperate to define a recess in the grounding plane and creating a recess space extending from the grounding plane with sides substantially perpendicular to the first face of the grounding plane; and

an antenna body electrically coupled to the grounding plane and having a radiation patch, the radiation patch positioned in a first plane substantially parallel to and spaced from the grounding plane, and the radiation patch suspended above the first face with at least a portion of the radiation patch extending into the recess space;
wherein the antenna body comprises a feed section connecting with the grounding plane, a grounding section connecting with the grounding plane, a first connection section connecting with the feed section, a second connection section connecting with the grounding section;
wherein the radiation patch comprises a first radiation section, a second radiation section and a third radiation section successively connecting with each other;
wherein the first radiation section, the second radiation section, the third radiation section, the first connection section, and the second connection section are coplanar;
wherein the first connecting section is spaced from the first radiation section and the third radiation section, and positioned between the first radiation section and the third radiation section; an end of the first connecting section is perpendicularly connected to the second radiation section, and another end of the first connecting section is spaced from the second connecting section.

2. The dual-band antenna structure of claim 1 , further comprising an adjusting element received in the recess and electrically coupling with the metallic middle frame and the grounding plane, a resonant frequency of the dual-band antenna structure being adjusted by adjusting a parameter of the adjusting element.

3. The dual-band antenna structure of claim 2 , wherein the adjusting element is an adjustable inductor and the parameter is a coefficient of self-inductance of the adjustable inductor.

4. The dual-band antenna structure of claim 1 , wherein the antenna body is a planar inverted-F antenna.

5. The dual-band antenna structure of claim 4 , wherein the radiation patch connecting with the first and second connecting sections, the radiation patch having a substantially U-shaped profile, the feed and the grounding sections are positioned in a second plane substantially perpendicular to the grounding plane.

6. The dual-band antenna structure of claim 5 , wherein the grounding plane is substantially rectangular and the recess is rectangular and defined in neighboring first and second sides of the grounding plane, the first and third radiation sections being parallel to the first side of the grounding plane, the second radiation section being parallel to the second side of the grounding plane and interconnecting ends of the first and third radiation sections away from the second side of the grounding plane.

7. The dual-band antenna structure of claim 6 , wherein the first radiation section is suspended above the recess and extends along a lengthwise direction of the recess.

8. The dual-band antenna structure of claim 7 , wherein the dual-band antenna structure has a first resonant frequency at a low frequency band of 2.4 GHz and a second resonant frequency at a high frequency band of 5.15-5.85 GHz.

9. The dual-band antenna structure of claim 8 , wherein the dual-band antenna structure is configured for Wi-Fi communication.

10. The dual-band antenna structure of claim 7 , further comprising an adjustable inductor located in the recess and electrically coupled to the metallic middle frame and the grounding plane, a distance between the second side of the grounding plane and the adjustable inductor is 15 mm, a length of the recess is 30 mm and a coefficient of self-inductance of the adjustable inductor is 2.6 nH.

11. An handheld electronic device, comprising:
a casing having a substantially rectangular metallic middle frame;
a substantially rectangular grounding plane received in the metallic middle frame, defining a recess in one of two top corners thereof; and
a planar inverted-F antenna for dual-band Wi-Fi communication having a feed section and a grounding section substantially perpendicularly connected to the grounding plane, and a substantially U-shaped radiation patch connected to the feed and grounding sections;
wherein the radiation patch is positioned in a first plane substantially parallel to and spaced from the grounding plane, and the radiation patch is suspended above the grounding plane and has at least a section located over the recess, the feed and the grounding sections are positioned in a second plane substantially perpendicular to the grounding plane;
wherein the antenna body comprises a feed section connecting with the grounding plane, a grounding section connecting with the grounding plane, a first connection section connecting with the feed section, a second connection section connecting with the grounding section;
wherein the radiation patch comprises a first radiation section, a second radiation section and a third radiation section successively connecting with each other;
wherein the first radiation section, the second radiation section, the third radiation section, the first connection section, and the second connection section are coplanar;
wherein the first connecting section is spaced from the first radiation section and the third radiation section, and positioned between the first radiation section and the third radiation section; an end of the first connecting section is perpendicularly connected to the second radiation section, and another end of the first connecting section is spaced from the second connecting section.

12. The handheld electronic device of claim 11 , further comprising an adjusting element located in the recess and electrically coupling with the grounding plane and the metallic middle frame, a resonant frequency of the planar inverted-F antenna at a low frequency band being adjustable by adjusting a parameter of the adjusting element.

13. The handheld electronic device of claim 12 , wherein the adjusting element is an adjustable inductor and the parameter is a coefficient of self-inductance of the adjustable inductor.

14. The handheld electronic device of claim 13 , wherein the radiation patch has a first radiation section, a second radiation section and a third radiation section successively connected together to form a U-shaped con

Assignees

• Chiun Mai Communication Systems Inc

Inventors

• Chang Tze Hsuan
• Hsu Cho Kang

Classifications

• H01Q9/42

  with folded element, the folded parts being spaced apart a small fraction of the operating wavelength · CPC title

• H01Q5/371

  Branching current paths · CPC title

• H01Q1/243

  with built-in antennas · CPC title

• H01Q9/0442

  with particular tuning means · CPC title

• H01Q1/48 Primary

  Earthing means; Earth screens; Counterpoises · CPC title