Space-filling miniature antennas

• US 10,355,346 B2
• Filed: 03/29/2016
• Issued: 07/16/2019
• Est. Priority Date: 01/19/2000
• Status: Expired due to Fees

• Current Assignee: Fractus SA
• Original Assignee: Fractus SA
• Inventors: Puente Baliarda, Carles, Jean Louis Rozan, Edouard, Anguera Pros, Jaume
• Primary Examiner(s): Levi, Dameon E
• Assistant Examiner(s): Dawkins, Collin
• Application Number:
  US15/084,140
• Publication Number:
  US 20160285168A1
• Time in Patent Office: 1,204 Days
• Field of Search: 343700 MS, 343702, 343725, 343892
• CPC Class Codes: H01Q 1/36 Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewithH01Q1/08, H01Q1/14 take precedence
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 13/10 Resonant slot antennas
• CPC Class Codes: H01Q 5/25 Ultra-wideband [UWB] systems, e.g. multiple resonance systems; Pulse systems
• CPC Class Codes: H01Q 5/357 using a single feed point
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40
• CPC Class Codes: H01Q 9/40 Element having extended radiating surface
• CPC Class Codes: H01Q 9/42 with folded element, the folded parts being spaced apart a small fraction of the operating wavelength

Abstract

A novel geometry, the geometry of Space-Filling Curves (SFC) is defined in the present invention and it is used to shape a part of an antenna. By means of this novel technique, the size of the antenna can be reduced with respect to prior art, or alternatively, given a fixed size the antenna can operate at a lower frequency with respect to a conventional antenna of the same size.

Claims

1. A device comprising:

a monopole antenna entirely included within the device and comprising an antenna element and a ground plane, the antenna element having an entire perimeter shaped as a space-filling curve, wherein;

the space-filling curve comprises at least ten connected segments;

each segment is shorter than one tenth of at least one operating free-space wavelength of the monopole antenna;

the segments are spatially arranged such that no two adjacent and connected segments form another longer segment;

each pair of adjacent segments forms a corner;

none of the segments intersect with another segment other than to form a closed loop; and

the space-filling curve is shaped so that an arrangement of the segments does not include a subset of segments that is repeated through the space-filling curve, and the arrangement of the segments is not self-similar with respect to the entire space-filling curve.

2. The device of claim 1, wherein the monopole antenna is configured to simultaneously operate in at least first and second non-overlapping frequency bands.

3. The device of claim 2, wherein the first frequency band comprises 1,800 MHz and the second frequency band comprises 2,100 MHz.

4. The device of claim 2, wherein the first frequency band comprises 850 MHz and the second frequency band comprises 2,100 MHz.

5. The device of claim 1 wherein the antenna element extends out of the ground plane from a connection point near a surface of the ground plane.

6. The device of claim 5, wherein the at least ten connected segments comprising the space-filling curve are straight segments.

7. A device comprising:

an antenna entirely included within the device and comprising an antenna element and a ground plane, the antenna element having an entire perimeter shaped as a space-filling curve, wherein;

the space-filling curve comprises at least ten connected segments;

each segment is shorter than one tenth of at least one operating free-space wavelength of the antenna;

the segments are spatially arranged such that no two adjacent and connected segments form another longer segment;

each pair of adjacent segments forms a corner;

none of the segments intersect with another segment other than to form a closed loop;

the space-filling curve is shaped so that an arrangement of the segments does not include a continued repetition of some parts of itself, and the arrangement of the segments is not self-similar with respect to the entire space-filling curve; and

the space-filling curve has a box-counting dimension greater than one, with the box-counting dimension computed as the slope of a substantially straight portion of a line in a log-log graph over at least an octave of scales on the horizontal axis of the log-log graph.

8. The device of claim 7, wherein the space-filling curve has a box-counting dimension greater than 1.2.

9. The device of claim 8, wherein the space-filling curve has a box-counting dimension greater than 1.3.

10. The device of claim 9, wherein the space-filling curve has a box-counting dimension greater than 1.4.

11. The device of claim 10, wherein the space-filling curve has a box-counting dimension greater than 1.5.

12. The device of claim 8, wherein the antenna is configured to simultaneously operate in at least first and second non-overlapping frequency bands.

13. The device of claim 12, wherein the first frequency band comprises 1,800 MHz and the second frequency band comprises 2,100 MHz.

14. The device of claim 8, wherein the corners are curved.

15. A device comprising:

an antenna entirely included within the device and comprising an antenna element and a ground plane, the antenna element having an entire perimeter shaped as a space-filling curve, wherein;

the space-filling curve comprises at least ten connected segments;

each segment is shorter than one tenth of at least one operating free-space wavelength of the antenna;

the segments are spatially arranged such that no two adjacent and connected segments form another longer segment;

each pair of adjacent segments forms a corner;

none of the segments intersect with another segment other than to form a closed loop;

the space-filling curve is shaped so that an arrangement of the segments does not include a continued repetition of some parts of itself, and the arrangement of the segments is not self-similar with respect to the entire space-filling curve;

the space-filling curve has a box-counting dimension greater than one, with the box-counting dimension computed as the slope of a substantially straight portion of a line in a log-log graph over at least an octave of scales on the horizontal axis of the log-log graph; and

the antenna is configured to simultaneously operate in at least first and second non-overlapping frequency bands.

16. The device of claim 15, wherein the first frequency band comprises 1,800 MHz and the second frequency band comprises 2,100 MHz.

17. The device of claim 15, wherein the space-filling curve has a box-counting dimension greater than 1.3.

18. The device of claim 15, wherein the at least ten connected segments comprising the space-filling curve are straight segments.

19. The device of claim 15, wherein the corners are curved.

20. The device of claim 15, wherein the antenna element extends out of the ground plane from a connection point near a surface of the ground plane.