Antenna Configurations for Compact Device Wireless Communication

• US 20090115672A1
• Filed: 09/03/2008
• Published: 05/07/2009
• Est. Priority Date: 09/04/2007
• Status: Active Grant

• Current Assignee: NETGEAR, Inc.
• Original Assignee: Sierra Wireless Incorporated
• Inventors: Nysen, Paul A.
• Granted Patent: US 8,049,671 B2
• Time in Patent Office: Days
• US Class Current: 343/730
• CPC Class Codes: H01Q 1/2275 associated to expansion card or bus, e.g. in PCMCIA, PC cards, Wireless USB
• CPC Class Codes: H01Q 13/10 Resonant slot antennas
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 5/364 Creating multiple current paths
• CPC Class Codes: H01Q 9/285 Planar dipole H01Q9/065 takes precedence; patch antenna H01Q9/0407
• CPC Class Codes: H01Q 9/36 with top loading
• CPC Class Codes: H03H 7/48 Networks for connecting several sources or loads, working on the same frequency or frequency band, to a common load or source phase shifters providing two or more output signals H03H7/21
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity

Abstract

A diversity antenna for use with a portable host device such as a laptop computer, for example as part of a PCMCIA card pluggable into the laptop computer to enable wireless computer by the laptop computer, includes a main antenna and a diversity antenna. Various configurations for these antennas are possible, including the use of a balanced dipole as the main antenna element and a split diversity antenna for the diversity antenna element. The diversity antenna provides high isolation between the antenna elements and isolation from interfering self-noise generated by the host device.

Claims

1. A diversity antenna system for use with a host device and configured to provide isolation from radiated self-noise by the host device and to minimize interactions between antenna elements of the diversity antenna system, the diversity antenna system comprising:

a ground plane;

a main antenna coupled to the ground plane and having a common mode feed; and

a diversity antenna having first and second arms extending from the common-mode feed of the main antenna.

2. The diversity antenna system of claim 1, wherein the main antenna is a balanced dipole antenna.

3. The diversity antenna system of claim 1, wherein the main antenna is coupled to the ground plane by way of a balun.

4. The diversity antenna system of claim 1, wherein the polarization of the main antenna is orthogonal to polarization of a common mode of the diversity antenna.

5. The diversity antenna system of claim 1, wherein the diversity antenna includes a gap between the first and second arms, said gap configured to substantially reduce odd mode excitation from the main antenna.

6. The diversity antenna system of claim 1, wherein the diversity antenna is a top loaded monopole.

26. The diversity antenna system of claim 5, further comprising a power splitter configured to drive the first and second arms.

27. The diversity antenna system of claim 26, wherein the power splitter is a Wilkinson power splitter.

28. The diversity antenna system of claim 5, further comprising a matching circuit coupled across the gap between the first and second arms.

29. The diversity antenna system of claim 1, wherein the host device is a laptop computer having a top face and having a side face to which the diversity antenna system is coupled, the main antenna being configured to extend substantially in parallel to said top face and said side face.

7. A diversity antenna system for use with a host device and configured to provide isolation from radiated self-noise by the host device and to minimize interactions between antenna elements of the diversity antenna system, the diversity antenna system comprising:

a ground plane;

a main antenna including a first portion of the ground plane and a first notch formed in the first portion; and

a diversity antenna including a pair of balanced notches formed is a second portion of the ground plane.

8. The diversity antenna system of claim 7, wherein the diversity antenna further comprises a gap feed for combining the pair of notches.

9. The diversity antenna system of claim 8, wherein the diversity antenna further comprises a Wilkinson power splitter combiner configured to combine notch signals of the diversity antenna in phase.

30. The diversity antenna system of claim 7, wherein the host device is a laptop computer having a top face and having a side face to which the diversity antenna system is coupled, the main antenna being configured to extend substantially in parallel to said top face and said side face.

10. A diversity antenna system for use with a host device and configured to provide isolation from radiated self-noise by the host device and to minimize interactions between antenna elements of the diversity antenna system, the diversity antenna system comprising:

a ground plane;

a main antenna;

a diversity antenna orthogonal to the main antenna; and

a double balun configured to provide independent feeds to the main and diversity antennas.

11. The diversity antenna system of claim 10, wherein the diversity antenna is configured to use a common mode of the main antenna and the double balun to achieve a non-balanced dipole.

12. The diversity antenna system of claim 11, further comprising a jumper, wherein the double balun provides a main feed to the main antenna through a first portion of the double balun, and a dual feed, to the main and diversity antennas, through a second portion of the double balun, the jumper being configured to connect the dual feed and the diversity antenna feed.

13. The diversity antenna system of claim 10, wherein the main antenna is a balanced dipole antenna.

14. The diversity antenna system of claim 10, wherein the polarization of the main antenna is orthogonal to polarization of a common mode of the diversity antenna.

31. The diversity antenna system of claim 10, wherein the host device is a laptop computer having a top face and having a side face to which the diversity antenna system is coupled, the main antenna being configured to extend substantially in parallel to said top face and said side face.

15. A diversity antenna system for use with a host device having a ground plane, the diversity antenna system being configured to provide isolation from radiated self-noise by the host device and to minimize interactions between antenna elements of the diversity antenna system, the diversity antenna system comprising:

a main antenna;

a diversity antenna orthogonal to the main antenna;

a first balun coupled to the main antenna; and

a jumper configured as a second balun for exciting a common mode of the main antenna.

16. The diversity antenna system of claim 15, wherein the main and diversity antennas are dipoles.

17. The diversity antenna system of claim 16, wherein the main antenna includes a stem, the diversity antenna system being configured such that a common mode of the main antenna is operable as a counterpoise for the diversity antenna.

18. The diversity antenna system of claim 16, wherein the main antenna is a balanced dipole antenna.

32. The diversity antenna system of claim 15, wherein the host device is a laptop computer having a top face and having a side face to which the diversity antenna system is coupled, the main antenna being configured to extend substantially in parallel to said top face and said side face.

19. A diversity antenna system for use with a host device having a ground plane and a case, the diversity antenna system being configured to provide isolation from radiated self-noise by the host device and to minimize interactions between antenna elements of the diversity antenna system, the diversity antenna system comprising:

a main antenna coupled to the ground plane;

a balun having a gap and coupled to the main antenna;

a common mode feed for the main antenna, the common mode feed configured to excite the gap of the balun; and

a diversity antenna having first and second arms extending from the common mode feed, the diversity antenna being configured to use the case as a counterpoise.

20. The diversity antenna system of claim 19, wherein the main antenna is a balanced dipole antenna.

21. The diversity antenna system of claim 19, wherein the polarization of the main antenna is orthogonal to polarization of a common mode of the diversity antenna.

22. The diversity antenna system of claim 19, wherein the diversity antenna includes a gap between the first and second arms, said gap configured to substantially reduce odd mode excitation from the main antenna.

23. The diversity antenna system of claim 22, further comprising a power splitter configured to drive the first and second arms.

24. The diversity antenna system of claim 23, wherein the power splitter is a Wilkinson power splitter.

25. The diversity antenna system of claim 22, further comprising a matching circuit coupled across the gap between the first and second arms.

33. The diversity antenna system of claim 19, wherein the host device is a laptop computer having a top face and having a side face to which the diversity antenna system is coupled, the main antenna being configured to extend substantially in parallel to said top face and said side face.