Notched-fed antenna

• US 7,342,553 B2
• Filed: 01/12/2005
• Issued: 03/11/2008
• Est. Priority Date: 07/15/2002
• Status: Expired due to Term

• Current Assignee: Fractus SA
• Original Assignee: S. A. Fractus
• Inventors: Soler Castany, Jordi, Puente Baliarda, Carles
• Primary Examiner(s): Owens, Douglas W.
• Assistant Examiner(s): Alemu, Ephrem
• Application Number:
  US11/033,788
• Publication Number:
  US 20050116873A1
• Time in Patent Office: 1,154 Days
• Field of Search: 343/700.MS, 343/853, 343/846, 343/749, 343/830, 343/702
• US Class Current: 343/853
• 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 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 5/371 Branching current paths
• CPC Class Codes: H01Q 5/42 using two or more imbricated arrays H01Q5/49 takes precedence
• CPC Class Codes: H01Q 9/04 Resonant antennas
• CPC Class Codes: H01Q 9/045 with particular feeding means for circular polarisation H01Q9/0428
• CPC Class Codes: H01Q 9/16 with feed intermediate between the extremities of the antenna, e.g. centre-fed dipole H01Q9/44 takes precedence
• CPC Class Codes: H01Q 9/28 Conical, cylindrical, cage, strip, gauze, or like elements having an extended radiating surface; Elements comprising two conical surfaces having collinear axes and adjacent apices and fed by two-conductor transmission lines waveguide horns or mouths H01Q13/00; slot antennas H01Q13/00
• CPC Class Codes: H01Q 9/285 Planar dipole H01Q9/065 takes precedence; patch antenna H01Q9/0407
• CPC Class Codes: H01Q 9/30 with feed to end of elongated active element, e.g. unipole H01Q9/44 takes precedence
• CPC Class Codes: H01Q 9/40 Element having extended radiating surface

Abstract

A monopole or dipole antenna includes a radiating element having at least one notch. The at least one notch intersects at least at one point on an edge of the radiating element wherein the intersecting point is located at a distance to a feeding point. The distance being shorter than half a length of a longest edge of the radiating element. A maximum width of the at least one notch is narrower than a half of a longest length of the at least one notch.

Claims

1. An antenna comprising:

a radiating element including at least one notch that intersects at least at one point on an edge of said radiating element and at least a portion of said radiating element includes a multilevel structure, said intersecting point is located at a distance to a feeding point that is shorter than half a length of the longest edge of said radiating element; and

wherein the maximum width of said at least one notch is narrower than half of the length of said at least one notch and said antenna features a similar radiation pattern and input impedance at more than one frequency band.

2. The antenna according to claim 1, wherein the radiating element includes one notch.

3. The antenna according to claim 1, wherein the radiating element includes two notches.

4. The antenna according to claim 1, wherein the radiating element includes two notches, a first notch is inserted at one side of the feeding point, and a second notch is inserted at an opposite side of the feeding point.

5. The antenna according to claim 4, wherein the two notches have similar shapes.

6. The antenna according to claim 1, wherein the radiating element includes at least a first notch and a second notch, said second notch is different in shape from said first notch, being such difference in length, shape or both.

7. The antenna according to claim 1, wherein the antenna includes at least one notch shaped as a curve intersecting itself at least at one point.

8. The antenna according to claim 1, wherein the antenna includes at least two notches, said at least two notches intersecting each other at least at one point.

9. The antenna according to claim 1, wherein a perimeter of said radiating element is a shape chosen from the following set:

triangular, square, rectangular, trapezoidal, pentagonal, hexagonal, heptagonal or octagonal.

10. The antenna according to claim 1, wherein a perimeter of said radiating element has a circular or elliptical shape, and for the circular or elliptical shape, the longest edge is considered as a quarter of the perimeter of the circular or elliptical shape.

11. The antenna according to claim 1, wherein the at least one notch is a curve composed by a minimum of two segments and a maximum of nine segments which are connected in such a way that each segment forms an angle with their neighbors and no pair of adjacent segments define a larger straight segment.

12. The antenna according to claim 1, wherein a shape of at least a portion of the at least one notch is a space-filling curve.

13. The antenna according to claim 1, wherein the radiating element includes at least a second conductor parallel to the radiating element, said second conductor being located at a distance from the radiating element smaller than a quarter of a central operating wavelength, and a space between the radiating element and said second conductor is filled with air or a dielectric or a combination of both.

14. The antenna according to claim 1, wherein said antenna is an element of an antenna array, said array including at least a notched-fed antenna.

15. The antenna according to claim 1, wherein the antenna is shorter than a quarter of a central operating wavelength.

16. The antenna according to claim 1, wherein the antenna includes a conducting or superconducting ground-plane.

17. The antenna according to claim 16, wherein the ground-plane is part of a handled case.

18. The antenna of claim 17, wherein the antenna is suitable for mobile communications and is placed inside a cellular phone or handheld wireless terminal.

19. The antenna of claim 17, wherein the antenna is excited by means of a transmission line, said transmission line including first and second conductors, said first conductor being connected to the ground-plane, and said second conductor being connected to a point of the radiating element.

20. The antenna according to claim 17, wherein the radiating element is printed over a dielectric substrate.

21. The antenna according to claim 20, wherein the dielectric substrate is part of the metallic structure of a handled telephone.

22. The antenna according to claim 20, wherein the antenna is adapted to transmit or receive electromagnetic waves of radio, or TV, or cellular telephone in the bands GSM 900, GSM 1800 or UMTS.