Antenna design using a slot architecture for global positioning system (GPS) applications

• US 6,606,072 B1
• Filed: 07/06/2001
• Issued: 08/12/2003
• Est. Priority Date: 07/06/2000
• Status: Expired due to Fees

• Current Assignee: Stata Labs LLC
• Original Assignee: Stata Labs LLC
• Inventors: Hayward, Roger, Glissman, John, Fuller, Richard, Marshall, Noel
• Primary Examiner(s): Clinger, James
• Application Number:
  US09/900,488
• Time in Patent Office: 767 Days
• Field of Search: 343/767, 343/702, 343/769, 343/718
• US Class Current: 343/767
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 13/10 Resonant slot antennas
• 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 GPS receiver includes a slot antenna having first and second surfaces. The second surface includes a semi-circular portion. The first and second surfaces define a slot within which is disposed dielectric material. The slot antenna is optimized for receiving GPS signals when in proximity to a human body. The relatively compact size of the slot antenna allows for the incorporation of the antenna into a small device that can be worn on or carried in close proximity to the body of a user. This type of antenna is not as sensitive to gain variations when in the proximity of a human body because the design has a wider aperture and thus operates better near the body. Further, this type of antenna is virtually omni-directional, i.e., it is not problematically sensitive to the location of the GPS signal source. Moreover, the design is such that the antenna arrangement can be oriented within a device in a way that maximizes the number of GPS satellites tracked.

Claims

1. An apparatus including circuitry for processing global positioning system (GPS) signals, said apparatus comprising:

a slot antenna, wherein said slot antenna includes;

a first surface, and

a second surface, wherein said second surface is perpendicular to said first surface, wherein said second surface includes a semi-circular portion, and wherein said first surface and said second surface define a slot having a dielectric material therein;

a feedline having one end coupled to said second surface; and

an amplifier coupled to another end of said feedline and configured to amplify signals received by said slot antenna.

2. The apparatus of claim 1, further comprising:

a housing that encloses said slot antenna and orients said slot antenna such that said first surface reduces an amount of interference due to a proximity of a user of said apparatus.

3. The apparatus of claim 1, wherein said feedline is coupled to said second surface at a location such that an impedance of said amplifier is matched.

4. The apparatus of claim 3, wherein said location is, from an end of said slot, a distance of between 10% and 20% of a total length of said slot.

5. The apparatus of claim 1, wherein said second surface has a length of between 75 and 95 millimeters.

6. The apparatus of claim 1, wherein said second surface has a width of between 5 and 10 millimeters.

7. The apparatus of claim 1, wherein said first surface has a semi-circular portion.

8. The apparatus of claim 1, wherein said first surface is formed to include a hole.

9. The apparatus of claim 8, wherein said feedline passes through said hole.

10. The apparatus of claim 1, wherein said first surface overlaps and is coincident with said second surface.

11. The apparatus of claim 1, wherein said slot antenna has a narrow bandwidth.

12. The apparatus of claim 11, wherein said narrow bandwidth is 5 MHz.

13. The apparatus of claim 1, further comprising:

a processor coupled to said amplifier, wherein said processor is configured to process said signals and to generate GPS data.

14. The apparatus of claim 1, further comprising:

a cellular telephone.

15. The apparatus of claim 1, further comprising:

a printed circuit board having said slot antenna attached thereto.

16. The apparatus of claim 1, further comprising:

a display device configured to display information related to said signals, wherein said display device has a height corresponding to a height of said second surface, and wherein said second surface partially surrounds said display device.

17. The apparatus of claim 1, wherein said slot has a length of between 65 and 85 millimeters.

18. The apparatus of claim 1, wherein said slot has a width of between 5 and 10 millimeters.

19. The apparatus of claim 1, wherein one or more portions of said slot antenna divide said slot into one or more segments.

20. An apparatus including circuitry for processing global positioning system (GPS) signals, said apparatus comprising:

a slot antenna, wherein said slot antenna includes;

a first surface, and

a second surface, wherein said second surface includes a semi-circular portion, and wherein said first surface and said second surface define a slot having a dielectric material therein;

a feedline having one end coupled to said second surface;

an amplifier coupled to another end of said feedline and configured to amplify signals received by said slot antenna; and

a display device configured to display information related to said signals, wherein said display device has a height corresponding to a height of said second surface, and wherein said second surface partially surrounds said display device.

21. The apparatus of claim 20, further comprising:

a housing that encloses said slot antenna and orients said slot antenna such that said first surface reduces an amount of interference due to a proximity of a user of said apparatus.

22. The apparatus of claim 20, wherein said feedline is coupled to said second surface at a location such that an impedance of said amplifier is matched.

23. The apparatus of claim 22, wherein said location is, from an end of said slot, a distance of between 10% and 20% of a total length of said slot.

24. The apparatus of claim 20, wherein said second surface has a length of between 75 and 95 millimeters.

25. The apparatus of claim 20, wherein said second surface has a width of between 5 and 10 millimeters.

26. The apparatus of claim 20, wherein said first surface has a semi-circular portion.

27. The apparatus of claim 20, wherein said first surface is formed to include a hole.

28. The apparatus of claim 27, wherein said feedline passes through said hole.

29. The apparatus of claim 20, wherein said first surface overlaps and is coincident with said second surface.

30. The apparatus of claim 20, wherein said slot antenna has a narrow bandwidth.

31. The apparatus of claim 30, wherein said narrow bandwidth is 5 MHz.

32. The apparatus of claim 20, further comprising:

a processor coupled to said amplifier, wherein said processor is configured to process said signals and to generate GPS data.

33. The apparatus of claim 20, further comprising:

a cellular telephone.

34. The apparatus of claim 20, further comprising:

a printed circuit board having said slot antenna attached thereto.

35. The apparatus of claim 20, wherein said slot has a length of between 65 and 85 millimeters.

36. The apparatus of claim 20, wherein said slot has a width of between 5 and 10 millimeters.

37. The apparatus of claim 20, wherein one or more portions of said slot antenna divide said slot into one or more segments.