Balanced Antenna Devices

• US 20080238800A1
• Filed: 09/18/2006
• Published: 10/02/2008
• Est. Priority Date: 09/19/2005
• Status: Abandoned Application

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Collins, Brian
• Application Number:
  US12/064,270
• Publication Number:
  US 20080238800A1
• Time in Patent Office: Days
• US Class Current: 343/795
• CPC Class Codes: H01Q 1/2275 associated to expansion card or bus, e.g. in PCMCIA, PC cards, Wireless USB
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 23/00 Antennas with active circuits or circuit elements integrated within them or attached to them
• CPC Class Codes: H01Q 9/26 with folded element or elements, the folded parts being spaced apart a small fraction of operating wavelength resonant loop antennas H01Q7/00
• CPC Class Codes: H01Q 9/285 Planar dipole H01Q9/065 takes precedence; patch antenna H01Q9/0407

Abstract

A balanced antenna comprising a dipole with first and second radiating arms, the radiating arms being provided with a balanced transmission line for connection to a feed, the balanced transmission line comprising first and second conductors connected to each other by a short-circuit conductor, and in which the antenna device is fed by applying a potential difference across the first and second conductors. The antenna device may be fed with an unbalanced feed, and is significantly smaller than a typical balanced dipole antenna device configured for operation at the same frequency.

Claims

1. A balanced antenna comprising a dipole with first and second radiating arms, the radiating arms being provided with a balanced transmission line for connection to a feed, the balanced transmission line comprising first and second conductors connected to each other by a short-circuit conductor, and in which the antenna device is fed by applying a potential difference across the first and second conductors.

2. An antenna device as claimed in claim 1, wherein the first and second radiating arms are formed as printed tracks on first and second opposed surfaces of a dielectric substrate.

3. An antenna device as claimed in claim 2, wherein the dielectric substrate is mounted vertically or near-vertically on a surface of a printed circuit board (PCB), the surface being provided with a conductive groundplane to which the first and second radiating arms are electrically connected.

4. An antenna device as claimed in claim 2, wherein the dielectric substrate is a PCB having first and second opposed surfaces each provided with a conductive groundplane except on predetermined opposing areas of the surfaces, and wherein the first and second radiating arms are formed on the predetermined areas of the surfaces.

5. An antenna device as claimed in claim 1, wherein the radiating arms have a meandering configuration.

6. An antenna device as claimed in claim 1, wherein the radiating arms are of different lengths.

7. An antenna device as claimed in claim 1, wherein the radiating arms do not follow identical paths.

8. An antenna device as claimed in claim 1, wherein the feed is an unbalanced feed.

9. An antenna device as claimed in claim 1, wherein the feed is a balanced feed.

10. An antenna device as claimed in claim 9, wherein the unbalanced feed comprises a coaxial cable, microstrip transmission line, coplanar waveguide or tri-plate waveguide.

11. An antenna device as claimed in claim 3, wherein at least one radiating arm is additionally connected to the groundplane by at least one inductive or capacitive component.

13. An antenna device as claimed in claim 1, wherein a radio-frequency integrated circuit is mounted on the transmission line

14. An antenna device as claimed in claim 1, wherein the antenna is mounted on an electronic memory card.

12. (canceled)

15. (canceled)