Antenna Structures Having Slot-Based Parasitic Elements

• US 20130293425A1
• Filed: 05/04/2012
• Published: 11/07/2013
• Est. Priority Date: 05/04/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Zhu, Jiang, Guterman, Jerzy, Pascolini, Mattia, Hu, Hongfei
• Granted Patent: US 9,203,139 B2
• Time in Patent Office: Days
• US Class Current: 343/702
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 1/521 reducing the coupling between adjacent antennas
• CPC Class Codes: H01Q 13/10 Resonant slot antennas
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 9/42 with folded element, the folded parts being spaced apart a small fraction of the operating wavelength

Abstract

Electronic devices may include radio-frequency transceiver circuitry and antenna structures. The antenna structures may include antenna resonating elements and antenna ground plane structures. An electronic device may have antennas formed from the antenna resonating elements and an antenna ground plane. The antenna ground plane may have slot structures. The slot structures may be configured to form a slot-based parasitic antenna element to minimize coupling between the antennas in a device. The slot-based parasitic antenna element may be located between the antennas in a device. The slots structures from which a parasitic antenna element is formed may include open slots and closed slots. Slots may have one or more arms and one or more bends. Slots may be formed in internal housing members, traces on dielectric carriers, and other conductive structures.

Claims

1. Apparatus, comprising:

an antenna ground plane;

a first antenna resonating element;

a second antenna resonating element; and

a slot-based parasitic antenna element formed from slot structures in the antenna ground plane, wherein the first antenna resonating element and the antenna ground plane form a first antenna, wherein the second antenna resonating element and the antenna ground plane form a second antenna, and wherein the slot-based parasitic antenna element is configured to serve as an antenna isolation element to minimize coupling between the first and second antennas.

2. The apparatus defined in claim 1 wherein the slot structures comprise an open slot in the antenna ground plane.

3. The apparatus defined in claim 2 wherein the open slot comprises an L-shaped slot having an end with an opening and having a bend.

4. The apparatus defined in claim 1 wherein the slot structures comprise two open slots in the antenna ground plane.

5. The apparatus defined in claim 4 wherein the two open slots have different lengths.

6. The apparatus defined in claim 1 wherein the slot structures comprise a T-shaped open slot with first and second arms of different lengths.

7. The apparatus defined in claim 1 wherein the slot structures comprise a closed slot in the antenna ground plane.

8. The apparatus defined in claim 7 wherein the closed slot has a C-shape.

9. The apparatus defined in claim 7 wherein the closed slot has an H-shape.

10. The apparatus defined in claim 1 wherein portions of the antenna ground plane are configured to form antenna cavity structures for the first and second antennas.

11. The apparatus defined in claim 1 wherein the slot structures are interposed between the first and second antennas.

12. The apparatus defined in claim 1 further comprising an electronic device housing having opposing first and second ends, wherein the first antenna is located in the first end and wherein the second antenna is located in the second end.

13. The apparatus defined in claim 1 wherein the slot structures are formed in the antenna ground plane at a location that is interposed between the first end and the second end and wherein the slot antenna structures include at least one closed slot.

14. The apparatus defined in claim 13 wherein the electronic device housing includes a midplate structure formed from sheet metal and wherein the closed slot is formed in the midplate structure.

15. The apparatus defined in claim 14 wherein the closed slot comprises an H-shaped closed slot.

16. An electronic device, comprising:

a housing having first and second ends;

an antenna ground plane;

a first antenna resonating element at the first end;

a second antenna resonating element at the second end; and

a slot-based parasitic antenna element formed from slot structures in the antenna ground plane, wherein the first antenna resonating element and the antenna ground plane form a first antenna, wherein the second antenna resonating element and the antenna ground plane form a second antenna, and wherein the slot-based parasitic antenna element is configured to serve as an antenna isolation element to minimize coupling between the first and second antennas.

17. The electronic device defined in claim 16 wherein the slot structures comprise at least one closed slot in the antenna ground plane between the first and second ends.

18. The electronic device defined in claim 17 further comprising an internal metal housing structure that forms at least part of the antenna ground plane, wherein the closed slot is formed in the internal metal housing structure.

19. The electronic device defined in claim 18 wherein the internal metal housing structure comprises at least one planar metal layer in which the closed slot is formed and wherein the electronic device comprises cellular telephone transceiver circuitry coupled to the first and second antennas.

20. An electronic device, comprising:

a housing having edges;

an antenna ground plane;

a first antenna resonating element at a first location along a given of the edges;

a second antenna resonating element at a second location along the given one of the edges; and

a slot-based parasitic antenna element formed from slot structures in the antenna ground plane, wherein the first antenna resonating element and the antenna ground plane form a first antenna, wherein the second antenna resonating element and the antenna ground plane form a second antenna, and wherein the slot-based parasitic antenna element is located along the given one of the edges between the first and second antennas and is configured to serve as an isolation element to minimize coupling between the first and second antennas.

21. The electronic device defined in claim 20 wherein the antenna ground plane includes portions configured to form antenna cavity structures for the first and second antennas.

22. The electronic device defined in claim 21 wherein the slot structures comprise at least one open slot.

23. The electronic device defined in claim 22 wherein the open slot has at least one bend.

24. The electronic device defined in claim 20 wherein the slot structures comprise at least one closed slot.

25. The electronic device defined in claim 20 wherein the antenna ground plane comprises a patterned metal layer on a dielectric support structure.