High-bandwidth multi-band antenna

• US 7,109,921 B2
• Filed: 12/19/2002
• Issued: 09/19/2006
• Est. Priority Date: 12/19/2001
• Status: Expired due to Fees

• Current Assignee: Harada Industry Company Limited
• Original Assignee: Harada Industry Company Limited
• Inventors: Leelaratne, Dedimuni Rusiru Vinodaka
• Primary Examiner(s): Ho, Tan
• Application Number:
  US10/499,523
• Publication Number:
  US 20050140549A1
• Time in Patent Office: 1,370 Days
• Field of Search: 343/700.MS, 343/846
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 9/0421 with a shorting wall or a shorting pin at one end of the element H01Q9/0414 takes precedence
• CPC Class Codes: H01Q 9/045 with particular feeding means for circular polarisation H01Q9/0428
• CPC Class Codes: H01Q 9/0457 electromagnetically coupled to the feed line

Abstract

A high-bandwidth multi-band antenna includes a ground plane member, a first patch member extending in generally-parallel spaced relationship with the ground plane member and electrically connected thereto, and a second patch member connectable to a signal feedline and extending generally coplanar with the first patch member within a slot formed in the first patch member. The second patch member is formed integral with a vertical conductive connecting member as part of a folded conducting plate; this construction allows the second patch member to be quickly and accurately positioned relative to the ground plane member before attachement to the ground plane member. The antenna has the advantages of a high bandwidth, simple construction and inexpensive manufacture.

Claims

1. A high-bandwidth multi-band antenna comprising a grounded patch member, a further patch member extending in generally-parallel spaced relationship with the grounded patch member and being electrically connected thereto, and a feed means adapted to carry a feedline signal, the feed means terminating at a termination that is generally coplanar with the further patch member and occupies part of a void space in the further patch member, a slot being thereby defined between the further patch member and the termination, the further patch member and the termination being capacitively coupled across the slot.

2. The antenna as described in claim 1, wherein the termination is a feed patch member, and wherein dimensions of the feed patch member and the width of the slot are selected such that each is within a respective range in which the bandwidth of the antenna varies with the slot width.

3. The antenna as described in claim 2, wherein the grounded patch member, the further patch member and the feed patch member are each formed as a conductive surface on a dielectric support.

4. The antenna as described in claim 2, wherein the further patch member and feed patch member both have a rectangular shape with longer first edges of each being oriented in the same direction.

5. The antenna as described in claim 4, wherein a frequency bandwidth for a higher one of the resonant frequencies of the antenna increases with a reduction in the length of the further patch member.

6. The antenna as described in claim 4, wherein a lowest resonant frequency of the antenna decreases with a reduction in the length of the further patch member.

7. The antenna as described in claim 2, and also comprising a radiating element connecting a portion of an edge of the grounded patch member to a portion of an edge of the further patch member such that the grounded patch member, radiating element and further patch member form a generally U-shaped configuration, wherein the grounded patch member, further patch member, feed patch member and radiating element all extend in the same plane.

8. The antenna as described in claim 7, and also comprising a feedline patch member connected to the feed patch member, the feedline patch member extending generally parallel to the radiating element and toward the grounded patch member in the plane of the further patch member, feed patch member and radiating element.

9. The antenna as described in claim 8, wherein the grounded patch member, further patch member, feed patch member, feedline patch member and radiating element are each formed as a conductive surface on a dielectric support.

10. The antenna as described in claim 1, and also comprising a discrete capacitor connected between the termination and the further patch member.

11. The antenna as described in claim 2, wherein the further patch member is electrically connected to the grounded patch member by a radiating element extending between the grounded patch member and one first edge of the further patch member.

12. The antenna as described in claim 11, wherein a first edge of the radiating element is connected to the one first edge of the further patch member.

13. The antenna as described in claim 11, wherein the feed patch member extends inwardly from an unconnected portion of the one first edge of the further patch member.

14. The antenna as described in claim 11, wherein the further patch member and the radiating element are integrally formed from a conductive sheet and separated by a fold-line in the sheet.

15. The antema as described in claim 14, and also comprising a solid dielectric material extending in the space that separates the grounded patch member from the further patch member and the feed patch member.

16. The antenna as described in claim 11, wherein the resonant frequencies of the antenna increase with an increase in the width of the radiating element.

17. The antenna as described in claim 11, wherein the radiating element is comprised of a series of parallel strips, each strip extending between the grounded patch member and the one first edge of the further patch member.

18. The antenna as described in claim 1, wherein the antenna operates in a first band in the range of 900 MHz and in a second band in the range of 1800 MHz.

19. The antenna as described in claim 18, wherein the antenna also operates in a third band in the range of 2200 MHz.