Multiband antenna

• US 8,228,245 B2
• Filed: 10/22/2010
• Issued: 07/24/2012
• Est. Priority Date: 10/16/2001
• Status: Expired due to Term

• Current Assignee: Fractus SA
• Original Assignee: Fractus SA
• Inventors: Quintero Illera, Ramiro, Puerlte Baliarda, Carles
• Primary Examiner(s): PHAN, THO GIA
• Application Number:
  US12/910,016
• Publication Number:
  US 20110260926A1
• Time in Patent Office: 641 Days
• Field of Search: 343/700.MS, 343/702, 343/829, 343/846
• US Class Current: 343/702
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 5/357 using a single feed point
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40
• 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 9/0442 with particular tuning means

Abstract

A multiband antenna includes at least two polygons. The at least two polygons are spaced by means of a non-straight gap shaped as a space-filling curve, in such a way that the whole gap length is increased yet keeping its size and the same overall antenna size allowing for an effective tuning of frequency bands of the anenna.

Claims

1. A wireless handheld or portable device comprising:

a substantially rectangular ground plane;

a multiband antenna formed by a multilevel conducting structure;

wherein said multiband antenna is integrated within the wireless handheld or portable device;

wherein the multilevel conducting structure comprises a plurality of polygons defined by a free perimeter thereof and a projection of a longest exposed perimeter thereof to define the least number of generally identifiable polygons having an equal number of sides or faces;

wherein a contact region between directly connected polygons is narrower than 50% of the perimeter of said polygons in at least 75% of said plurality of polygons;

wherein polygons of a subset of said plurality of polygons are electromagnetically coupled in multiple frequency bands; and

wherein at least two polygons of the plurality of polygons are separated by a non-straight gap.

2. The wireless handheld or portable device of claim 1, wherein the multiband antenna is inscribed in a rectangular area having a longest dimension substantially parallel to a shortest side of the substantially rectangular ground plane, and wherein the multiband antenna is placed substantially close to said shortest side.

3. The wireless handheld or portable device of claim 1, wherein the non-straight gap is placed between two polygons, and wherein said two polygons are electromagnetically coupled at multiple frequency bands.

4. The wireless handheld or portable device of claim 1, wherein the non-straight gap comprises at least one curve selected from the group comprising a meandering curve, a periodic curve, a branching curve comprising a main longer curve and at least one added segment or branching curves departing from a point of said main longer curve, an arbitrary curve, or a combination thereof, and wherein said curve includes at least five segments.

5. The wireless handheld or portable device of claim 1, wherein the non-straight gap modifies a frequency response of the multiband antenna relative to a multiband antenna comprising an otherwise identical gap without the non-straight gap.

6. The wireless handheld or portable device of claim 1, wherein the non-straight gap tunes the multiband antenna to operate in a further frequency band while keeping an overall size of the multiband antenna.

7. The wireless handheld or portable device of claim 1, wherein the non-straight gap reduces an overall size of the multiband antenna while maintaining its frequency response relative to a multiband antenna comprising an otherwise identical gap without the non-straight gap.

8. The wireless handheld or portable device of claim 1, wherein the non-straight gap is located proximate to a feeding point of the multiband antenna.

9. The wireless handheld or portable device of claim 1, wherein the multiband antenna comprises a second non-straight gap.

10. The wireless handheld or portable device of claim 9, wherein the second non-straight gap tunes the multiband antenna to operate in a further frequency band.

11. The wireless handheld or portable device of claim 1, wherein the multiband antenna operates at least five frequency bands associated to licensed services preferably selected from the group comprising:

Bluetooth, 2.4 GHz Bluetooth, GPS, LTE, GSM 850, GSM 900, GSM 1800, GSM 1900, DCS, PCS, UMTS, CDMA, DMB, DVB-H, WLAN, WCDMA, DAB, WiFi, UWB, 2.4-2.483 GHz band, 2.471-2.497 GHz band, IEEE802.11ba, IEEE802.11b, IEEE802.11g and FM.

12. The wireless handheld or portable device according to claim 1, wherein the multiband antenna is a monopole antenna, and wherein a major portion of an area of the monopole antenna does not overlap the substantially rectangular ground plane.

13. The wireless handheld or portable device of claim 1, wherein said wireless handheld or portable device is selected from the group consisting of a cellular phone, a mobile phone, a handheld phone, a handset, a smart phone, a satellite phone, a multimedia terminal, personal digital assistant (PDA), a personal computer, a Notebook, PC, a pocket PC, a laptop, a portable computer, a palmtop, a laptop, a personal digital assistants, and a tablet.

14. The wireless handheld or portable device according to claim 1, wherein the multiband antenna is a patch antenna, and wherein said patch antenna is placed over a dielectric substrate.

15. A wireless handheld or portable device comprising:

a substantially rectangular ground plane;

a multiband antenna formed by a multilevel conducting structure;

wherein said multiband antenna is integrated within the wireless handheld or portable device;

wherein the multilevel conducting structure comprises a plurality of generally identifiable polygons having an equal number of sides or faces;

wherein the plurality of polygons define at least two portions;

a first portion defining a current path in a first operating frequency band and a second portion defining a current path in a second operating frequency band;

wherein the first portion and the second portion overlap at least partially with each other;

wherein at least two polygons of the plurality of polygons are separated by a non-straight gap; and

wherein a longest dimensions of the first portion divided by a longest free-space operating wavelength of the first frequency band is smaller than ¼

.

16. The wireless handheld or portable device of claim 15, wherein the multiband antenna includes a loading capacitor placed at one edge of the multiband antenna.

17. The wireless handheld or portable device of claim 15, wherein the non-straight gap is shaped as a space-filling curve comprising segments shorter than a tenth of a free-space operating wavelength.

18. The wireless handheld or portable device according to claim 15, wherein the non-straight gap reduces an overall size of the multiband antenna while maintaining its frequency response relative to a multiband antenna comprising an otherwise identical gap without the non-straight gap.

19. The wireless handheld or portable device according to claim 15, wherein the substantially rectangular ground plane is formed with two conducting surfaces, and wherein said two conducting surfaces are connected by means a conducting strip.

20. The wireless handheld or portable device according to claim 15, wherein the non-straight gap tunes the multiband antenna to operate at five frequency bands, and wherein at least two frequency bands are used by a GSM and UMTS communication service.