Diversity antenna system including two planar inverted F antennas

• US 6,483,463 B2
• Filed: 03/27/2001
• Issued: 11/19/2002
• Est. Priority Date: 03/27/2001
• Status: Expired due to Term

• Current Assignee: Laird Connectivity Inc.
• Original Assignee: Centurion Industries Incorporated (Laird Limited)
• Inventors: Kadambi, Govind R., Yarasi, Sripathi, Simmons, Kenneth D.
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): VANNUCCI, JAMES
• Application Number:
  US09/818,410
• Publication Number:
  US 20020140612A1
• Time in Patent Office: 602 Days
• Field of Search: 343/700.MS, 343/702, 343/725, 343/846, 455/90, 455/273
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 25/005 providing two patterns of opposite direction; back to back antennas H01Q25/004 takes precedence
• CPC Class Codes: H01Q 9/0421 with a shorting wall or a shorting pin at one end of the element H01Q9/0414 takes precedence

Abstract

A diversity antenna comprising two planar inverted F antennas (PIFAs) characterized by: two radiating elements with or without the physical separation between them; the spatially separable radiating elements of the two PIFAs with side-by-side or orthogonal placement with respect to each other are combined to form an equivalent single element consisting of the composite assembly of two radiators; a small ground plane of rectangular or L-shape with or without bending at its opposite ends is common to both the radiating elements; the radiating elements are placed above the unbent common ground plane; the radiating elements are placed above the vertical sections of the bent common ground plane; the shorted ends of the spatially separated radiating elements are placed back to back on the said common ground plane; a common shorting post placed along the common boundary line resulted by the merging of the two radiators with a prior side by side mutual placement; a common shorting post placed within the common boundary surface resulted by the merging of the two radiators with a prior mutual orthogonal orientation.

Claims

1. A diversity antenna comprising two planar inverted F antennas (PIFAs), comprising:

first and second spaced-apart radiating elements; and

said first and second radiating elements being positioned over a ground plane which is common to both of said first and second radiating elements;

said ground plane having a length smaller than one-quarter wavelength.

2. The diversity antenna of claim 1 wherein said first and second radiating elements are formed from a single element so that they are of one-piece unitary construction, but are RF spaced-apart by means of a shorting post that extends between said first and second radiating elements and said common ground plane.

3. The diversity antenna of claim 1 wherein said first and second rectangular shaped radiating elements are oriented orthogonally with respect to one another.

4. The diversity antenna of claim 3 wherein said first and second rectangular shaped radiating elements define an L-shape.

5. The diversity antenna of claim 4 wherein said radiating elements are formed from a single element so that they are of one-piece unitary construction, but are RF spaced-apart by means of a shorting post that extends between said first and second radiating elements and said common ground plane.

6. A diversity antenna comprising two planar inverted F antennas (PIFAs), comprising:

first and second spaced-apart radiating elements; and

said first and second radiating elements being positioned over a ground plane which is common to both of said first and second radiating elements;

said first and second radiating elements having ends which are shorted to said common ground plane;

said shorted ends of said first and second radiating elements being positioned back-to-back on said common ground plane to minimize the mutual coupling between said first and second radiating elements.

7. The diversity antenna of claim 6 wherein said common ground plane has opposite ends and wherein said common ground plane is bent downwardly at its opposite ends thereby forming first and second vertical sections.

8. A diversity antenna comprising two planar inverted F antennas (PIFAs), comprising:

first and second spaced-apart radiating elements;

said first and second radiating elements being positioned over a ground plane which is common to both of said first and second radiating elements;

said first and second radiating elements having ends which are shorted to said common ground plane;

said shorted ends of said first and second radiating elements being positioned back-to-back on said common ground plane to minimize the mutual coupling between said first and second radiating elements;

said common ground plane having opposite ends and wherein said common ground plane is bent downwardly at its opposite ends, thereby forming first and second vertical sections;

said first and second radiating elements being positioned above said first and second vertical sections, respectively.

9. The diversity antenna of claim 8 wherein said first and second radiating elements are positioned outwardly with respect to said first and second vertical sections of said common ground plane, respectively.

10. A diversity antenna comprising two planar inverted F antennas (PIFAs), comprising:

first and second spaced-apart radiating elements; and

said first and second radiating elements being positioned over an L-shaped ground plane which is common to both of said first and second radiating elements;

said first and second radiating elements being oriented orthogonally with respect to one another to define an L-shape.