OMNIDIRECTIONAL MULTI-BAND ANTENNAS

• US 20120169560A1
• Filed: 03/14/2012
• Published: 07/05/2012
• Est. Priority Date: 10/30/2009
• Status: Active Grant

• Current Assignee: TE Connectivity Solutions GmbH (TE Connectivity Ltd. (United Kingdom))
• Original Assignee: Laird Technologies Incorporated (DuPont de Nemours, Inc.)
• Inventors: Lee, Ting Hee, Jiunn, Ng Kok, Meng, Ooi Tze
• Granted Patent: US 8,866,685 B2
• Time in Patent Office: Days
• US Class Current: 343/770
• CPC Class Codes: H01Q 21/10 Collinear arrangements of substantially straight elongated conductive units
• CPC Class Codes: H01Q 5/00 Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements combinations of separate active antenna units operating in different wavebands and connected to a common feeder system H01Q21/30
• CPC Class Codes: H01Q 5/371 Branching current paths
• 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 9/30 with feed to end of elongated active element, e.g. unipole H01Q9/44 takes precedence

Abstract

Disclosed herein are various exemplary embodiments of omnidirectional multi-band antennas. In an exemplary embodiment, an antenna includes upper and lower portions. The upper portion includes one or more radiating elements, one or more tapering features for impedance matching, and one or more slots configured to enable multi-band operation of the antenna. The lower portion includes one or more radiating elements and one or more slots.

Claims

1. An omnidirectional multi-band antenna comprising:

an upper portion including at least one segment having one or more upper radiating elements, one or more tapering features, and one or more slots;

a lower portion including one or more lower radiating elements and one or more slots;

whereby the one or more slots of the upper and lower portions enable multi-band operation of the antenna and the one or more tapering features are operable for impedance matching;

whereby the antenna is operable within a first frequency range, with the lower portion and the at least one segment of the upper portion each having an electrical length of about λ

/4; and

whereby the antenna is operable within a second frequency range, with the lower portion and the at least one segment of the upper portion each having an electrical length of about λ

/2.

2. The antenna of claim 1, wherein:

the first frequency range is the 2.45 gigahertz band from about 2.4 gigahertz to about 2.5 gigahertz, and

the second frequency range is the 5 gigahertz band from about 4.9 gigahertz to about 5.875 gigahertz.

3. The antenna of claim 1, wherein:

the upper portion includes three segments each including one or more upper radiating elements;

the antenna is configured to be operable within the first frequency range, such that each of the three segments of the upper portion have an electrical length of about λ

/4, thereby providing the upper portion with a combined electrical length of about 3λ

/4; and

the antenna is configured to be operable within the second frequency range, such that each of the three segments of the upper portion have an electrical length of about λ

/2, thereby providing the upper portion with a combined electrical length of about 3λ

/2.

4. The antenna of claim 1, wherein the upper portion comprises:

upper and lower segments each having one or more upper radiating elements, one or more tapering features, and one or more slots; and

a middle generally straight segment between and connected to the upper and lower segments.

5. The antenna of claim 1, wherein:

the upper portion includes only one segment;

the antenna is configured to be operable within the first frequency range, such that the upper portion has an electrical length of about λ

/4; and

the antenna is configured to be operable within the second frequency, such that the upper portion has an electrical length of about λ

/2.

6. The antenna of claim 1, wherein the one or more tapering features comprise at least one generally V-shaped edge of at least one radiating element of the at least one segment of the antenna'"'"'s upper portion, and wherein the at least one generally V-shaped edge is spaced apart from the antenna'"'"'s lower portion and oriented so as to point generally toward the antenna'"'"'s lower portion.

7. The antenna of claim 1, wherein:

the lower portion comprises a planar skirt element; and

/or

the lower portion is configured to be operable as a quarter wavelength (λ

/4) choke at the first frequency range, such that at least a portion of the antenna current does not leak into an outer surface of a coaxial cable when the antenna is being fed by the coaxial cable; and

/or

the lower portion is configured to be operable as ground; and

/or

the lower portion is operable as a sleeve choke at the first frequency range; and

/or

the lower portion comprises two generally rectangular radiating elements and a generally rectangular ground element disposed between the two radiating elements, the two radiating elements spaced apart from the ground element by the one or more slots of the lower portion of the antenna, the two radiating elements and ground element generally perpendicular to and connected to a generally rectangular connecting radiating element.

8. The antenna of claim 1, wherein the one or more slots of the at least one segment of the antenna'"'"'s upper portion include a generally rectangular or triangular portion and two generally straight portions connected to and extending from the generally rectangular or triangular portion.

9. The antenna of claim 8, wherein:

the one or more slots of the at least one segment of the antenna'"'"'s upper portion further comprise inwardly angled end portions connected to the straight portions; and

/or

the one or more slots of the at least one segment of the antenna'"'"'s upper portion include the generally rectangular portion adjacent an upper end of the at least one segment; and

/or

the one or more slots of the at least one segment of the antenna'"'"'s upper portion include the generally triangular portion adjacent the one or more tapering features of the at least one segment.

10. The antenna of claim 1, wherein:

the upper radiating elements comprise high and low band radiating elements with one or more slots therebetween; and

the antenna is configured such that;

at the first frequency range, the low band radiating element has an electrical length of about λ

/4; and

at the second frequency range, the high and low band radiating elements respectively have electrical lengths of about λ

/4 and λ

/2.

11. The antenna of claim 10, wherein:

the high band radiating element includes a generally rectangular shaped portion connected to the one or more tapering features; and

the low band radiating element includes two generally straight portions connected to the one or more tapering features and extending alongside the generally rectangular portion of the high band radiating element.

12. The antenna of claim 11, wherein:

the generally rectangular shaped portion and the one or more tapering features cooperatively define an arrow shape; and

/or

the low band radiating element further comprises;

a connecting element connecting the end portions of the generally straight portions;

or

two end portions generally perpendicular to and extending inwardly from a corresponding one of the generally straight portions and/or two generally L-shaped portions.

13. The antenna of claim 1, wherein the one or more slots of the at least one segment of the antenna'"'"'s upper portion generally define a shape substantially resembling the English alphabetic letter “

v”

or “

n”

.

14. The antenna of claim 1, wherein:

the antenna is operable with at least about 2 decibels referenced to isotropic gain (dBi) for the 2.45 gigahertz band and with more than 4 dBi for the 5 gigahertz band; and

/or

the antenna is configured such that;

the antenna operates essentially as a standard half wavelength dipole antenna at the 2.45 gigahertz band and a wavelength dipole antenna at the 5 gigahertz band;

or

the antenna operates essentially as a wavelength dipole antenna at the 2.45 gigahertz band and a collinear array antenna at the 5 gigahertz band.

15. The antenna of claim 1, wherein:

the radiating elements, the one or more tapering features, and the one or more slots are on the same side of a printed circuit board; and

/or

the antenna further comprises a substrate supporting the upper and lower portions of the antenna on a same side of the substrate.

16. The antenna of claim 1, further comprising:

a coaxial cable having inner and outer conductors electrically coupled to the respective upper and lower portions of the antenna; and

/or

a circuit board supporting the upper and lower portions of the antenna on a same side of the circuit board, and wherein the upper and lower radiating elements comprise conductive traces on the circuit board.

17. An omnidirectional multi-band antenna comprising:

an upper portion including;

an upper segment having one or more upper radiating elements, one or more tapering features, and one or more slots;

a lower segment having one or more upper radiating elements, one or more tapering features, and one or more slots;

a middle generally straight radiating segment connected to the upper and lower segments;

a lower portion including one or more lower radiating elements and one or more slots.

18. The antenna of claim 17, wherein:

the antenna is configured to be operable within a first frequency range, such that the lower portion has an electrical length of about λ

/4 and such that each of the three segments of the upper portion have an electrical length of about λ

/4, thereby providing the upper portion with a combined electrical length of about 3λ

/4; and

the antenna is configured to be operable within a second frequency range, such that the lower portion has an electrical length of about λ

/2 and such that each of the three segments of the upper portion have an electrical length of about λ

/2, thereby providing the upper portion with a combined electrical length of about 3λ

/2.

19. The antenna of claim 18, wherein:

the first frequency range is the 2.45 gigahertz band from about 2.4 gigahertz to about 2.5 gigahertz; and

the second frequency range is the 5 gigahertz band from 4.9 gigahertz to 5.875 gigahertz.

20. The antenna of claim 17, wherein the one or more tapering features comprises at least one generally V-shaped edge of at least one radiating element of the corresponding upper and lower segments that is spaced apart from the antenna'"'"'s lower portion and oriented so as to point generally toward the antenna'"'"'s lower portion.

21. The antenna of claim 17, wherein:

the lower portion is configured to be operable as a quarter wavelength (λ

/4) choke at the first frequency range, such that at least a portion of the antenna current does not leak into an outer surface of a coaxial cable when the antenna is being fed by the coaxial cable; and

/or

the lower portion is operable as a sleeve choke at the first frequency range; and

/or

the lower portion is configured to be operable as ground; and

/or

the lower portion comprises two generally rectangular radiating elements and a generally rectangular ground element disposed between the two radiating elements, the two radiating elements spaced apart from the ground element by the one or more slots of the lower portion of the antenna, the two radiating elements and ground element generally perpendicular to and connected to a generally rectangular connecting radiating element.

22. The antenna of claim 17, wherein the one or more slots of each of the upper and lower segments includes a generally rectangular portion, two generally straight portions connected to and extending from the generally rectangular portion generally towards the antenna'"'"'s lower portion, and inwardly angled end portions connected to the straight portions.

23. The antenna of claim 17, wherein:

the upper segment includes a generally rectangular shaped portion connected to the one or more tapering features of the upper segment, two generally straight portions connected to the one or more tapering features, and a connecting element connecting the end portions of the generally straight portions; and

the lower segment includes a generally rectangular shaped portion connected to the one or more tapering features of the lower segment, and two generally L-shaped straight portions connected to the one or more tapering features and extending alongside the generally rectangular portion.

24. The antenna of claim 17, wherein:

the radiating elements, the one or more tapering features, and the one or more slots are on the same side of a printed circuit board; and

/or

the antenna further comprises a substrate supporting the upper and lower portions of the antenna on a same side of the substrate; and

/or

the antenna further comprises a circuit board supporting the upper and lower portions of the antenna on a same side of the circuit board, and wherein the radiating elements comprise conductive traces on the circuit board; and

/or

the antenna further comprises a coaxial cable having inner and outer conductors electrically coupled to the respective upper and lower portions of the antenna.

25. An omnidirectional multi-band antenna comprising:

an upper portion including one or more upper radiating elements and one or more slots, the one or more slots including a generally rectangular portion and two generally straight portions connected to and extending from the generally rectangular portion;

the one or more upper radiating elements comprise high and low band radiating elements with one or more slots therebetween, the high band radiating element includes a generally rectangular shaped portion, the low band radiating element includes two generally straight portions extending alongside the generally rectangular portion of the high band radiating element and two end portions generally perpendicular to and extending inwardly from a corresponding one of the generally straight portions; and

a lower portion including one or more lower radiating elements;

wherein at least one of the one or more upper radiating elements defining a generally V-shaped edge oriented so as to point generally toward the antenna'"'"'s lower portion.

26. The antenna of claim 25, wherein:

the antenna is operable within a first frequency range, with the upper and lower portions each having an electrical length of about λ

/4; and

the antenna is operable within a second frequency range, with the upper and lower portions each having an electrical length of about λ

/2.

27. The antenna of claim 26, wherein:

the first frequency range is the 2.45 gigahertz band from about 2.4 gigahertz to about 2.5 gigahertz; and

the second frequency range is the 5 gigahertz band from 4.9 gigahertz to 5.875 gigahertz.

28. The antenna of claim 26, wherein the antenna is configured such that:

at the first frequency range, the low band radiating element has an electrical length of about λ

/4; and

at the second frequency range, the high and low band radiating elements respectively have electrical lengths of about λ

/4 and λ

/2.

29. The antenna of claim 25, wherein:

the lower portion is configured to be operable as a quarter wavelength (λ

/4) choke at a first frequency range, such that at least a portion of the antenna current does not leak into an outer surface of a coaxial cable when the antenna is being fed by the coaxial cable; and

/or

the lower portion is operable as a sleeve choke at a first frequency range; and

/or

the lower portion is configured to be operable as ground.

30. The antenna of claim 25, wherein:

the antenna further comprises a coaxial cable having inner and outer conductors electrically coupled to the respective upper and lower portions of the antenna; and

/or

the radiating elements, the one or more tapering features, and the one or more slots are on the same side of a printed circuit board; and

/or

the antenna further comprises a substrate supporting the upper and lower portions of the antenna on a same side of the substrate; and

/or

the antenna further comprises a circuit board supporting the upper and lower portions of the antenna on a same side of the circuit board, and wherein the radiating elements comprise conductive traces on the circuit board.