Loaded antenna

• US 7,541,997 B2
• Filed: 07/03/2007
• Issued: 06/02/2009
• Est. Priority Date: 10/16/2001
• Status: Expired due to Fees

• Current Assignee: Fractus SA
• Original Assignee: Fractus SA
• Inventors: Soler Castany, Jordi, Puente Baliarda, Carles
• Primary Examiner(s): Wimer; Michael C
• Application Number:
  US11/824,823
• Publication Number:
  US 20080122715A1
• Time in Patent Office: 700 Days
• Field of Search: 343/700.MS, 343/752, 343/795, 343/829, 343/830, 343/846
• US Class Current: 343/752
• CPC Class Codes: H01Q 1/243 with built-in antennas
• 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 15/0093 having a fractal shape
• CPC Class Codes: H01Q 5/371 Branching current paths
• 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 9/0442 with particular tuning means
• CPC Class Codes: H01Q 9/285 Planar dipole H01Q9/065 takes precedence; patch antenna H01Q9/0407
• 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 loaded antenna is defined in the present invention. The radiating element of the loaded antenna consists of two different parts: a conducting surface and a loading structure. By means of this configuration, the antenna provides a small and multiband performance, and hence it features a similar behavior through different frequency bands.

Claims

1. A portable communications device comprising:

a case operable to be held in a user'"'"'s hand;

a grounding element;

an antenna mounted within the case in operative relation to the grounding element and operable to both radiate and receive electromagnetic waves across at least one industry-standard frequency band;

wherein the antenna comprises;

a radiating element disposed relative to the grounding element in a monopole configuration and comprising a first part and a second part;

wherein the first part comprises at least one conducting surface;

wherein the second part comprises a loading structure;

wherein the loading structure comprises at least one conducting strip connected at least two points on an edge of the at least one conducting surface;

wherein the maximal width of the at least one conducting strip is less than a quarter of the longest straight edge of the at least one conducting surface; and

wherein the loading structure causes the antenna to radiate and receive electromagnetic waves across at least one more industry-standard frequency band compared to an identical antenna without the loading structure.

2. The portable communications device of claim 1, wherein the grounding element comprises a ground plane.

3. The portable communications device of claim 2, wherein at least a part of the ground plane is formed by at least a portion of the case.

4. The portable communications device of claim 1, wherein:

a shape of at least one of the at least one conducting strip comprises a curve;

the curve comprises a minimum of two segments and a maximum of nine segments; and

each of the segments forms an angle with an adjacent segment of the segments so that no pair of adjacent segments of the segments defines a larger straight segment.

5. The portable communications device of claim 1, wherein two tips of at least one of the at least one conducting strip are connected at two points on a perimeter of the first part.

6. The portable communications device of claim 1, wherein:

the loading structure comprises at least two conducting strips; and

a tip of a first of the at least two conducting strips and a tip of a second of the at least two conducting strips are connected on an edge of the at least one conducting surface.

7. The portable communications device of claim 1, wherein:

the loading structure comprises at least two conducting strips; and

both tips of a first of the at least two conducting strips are connected to a second of the at least two conducting strips.

8. The portable communications device of claim 1, wherein:

the loading structure comprises at least two conducting strips; and

a first tip of a first of the at least two conducting strips is connected to a second of the at least two conducting strips; and

a second tip of the first of the at least two conducting strips is connected to the at least one conducting surface.

9. The portable communications device of claim 1, wherein the loading structure comprises at least two conducting strips connected at a plurality of points on a perimeter of the at least one conducting surface.

10. The portable communications device of claim 1, wherein at least one conducting surface and the loading structure lie on a common flat or curved surface.

11. The portable communications device of claim 1, wherein:

the antenna comprises at least two conducting surfaces;

a second conducting surface of the at least two conducting surfaces features a smaller area than a first conducting surface of the at least two conducting surfaces; and

at least one conducting strip of the at least one conducting strip is connected to the first conducting surface at a first end and to the second conducting surface at a second end.

12. The portable communications device of claim 1, wherein a perimeter of the at least one conducting surface is of shaped as one of a triangle, a square, a rectangle, a trapezoid, a pentagon, a hexagon, a heptagon, an octagon, a circle, and an ellipse.

13. The portable communications device of claim 1, wherein a perimeter of the at least one conducting surface is polygonal in shape.

14. The portable communications device of claim 1, wherein at least a part of a perimeter of the at least one conducting surface is shaped as a space-filling curve.

15. The portable communications device of claim 1, wherein at least a portion of the at least one conducting surface is shaped as a multilevel structure.

16. The portable communications device of claim 1, wherein:

the at least one conducting strip comprises a first conducting strip and a second conducting strip;

the first conducting strip is connected at least one point to a perimeter of the at least one conducting surface; and

a tip of the second conducting strip is connected to the first conducting strip.

17. The portable communications device of claim 1, wherein the maximal width of the at least one conducting strip is measured perpendicularly to a main axis along a length of the at least one conducting strip.

18. The portable communications device of claim 6, wherein a maximal width of each of the at least two conducting strips is measured perpendicularly to a main axis along a length thereof.

19. The portable communications device of claim 7, wherein a maximal width of each of the at least two conducting strips is measured perpendicularly to a main axis along a length thereof.

20. The portable communications device of claim 8, wherein a maximal width of each of the at least two conducting strips is measured perpendicularly to a main axis along a length thereof.

21. The portable communications device of claim 9, wherein a maximal width of each of the at least two conducting strips is measured perpendicularly to a main axis along a length thereof.

22. The portable communications device of claim 1, wherein the antenna is operable to radiate and receive electromagnetic waves across at least three industry-standard frequency bands.

23. The portable communications device of claim 22, wherein the at least three industry-standard frequency bands comprise GSM 900.

24. The portable communications device of claim 22, wherein the three industry-standard frequency bands comprise GSM 1800.

25. The portable communications device of claim 22, wherein the at least three industry-standard frequency bands comprise UMTS.