Multi-band Antenna of Compact Size

Abstract

A multi-band antenna of compact size includes a conductor of uniform cross-section folded to form the antenna with a connection portion, a low-frequency first radiation portion, and a high-frequency second radiation portion. The connection portion has a feeding point for signal feeding. The first and second radiation portions connect to two ends of the connection portion. The first radiation portion is folded along two different planes to form three main sections. The second radiation portion is folded along a plane to form two sections. A terminal section of the first radiation portion and a terminal section of the second radiation portion are parallel, such that radiation of these two sections is coupled to enhance radiation characteristics of the antenna. Also, the folded structure helps to achieve compact size of the antenna.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of an antenna of the prior art.

FIGS. 2-5 are diagrams of an embodiment of an antenna of the present invention from various perspectives.

FIGS. 6-9 present different portions of the antenna in FIG. 2.

FIG. 10 presents frequency characteristics formed by an intercoupling effect of high/low frequency radiation portions of the antenna of the present invention.

FIG. 11 is a diagram of a voltage standing wave ratio (VSWR) of the antenna of the present invention in practice.

FIG. 12 is a diagram of the antenna in FIG. 2 installed on a circuit board.

FIGS. 13-16 are diagrams of the antenna in FIG. 2 installed on a fixture.

FIGS. 17-18 are diagrams of the antenna in FIG. 2 embedded in a circuit board.

FIGS. 19-26 presents various embodiments of the antenna of the present invention respectively.

Claims

1. A multi-band antenna comprising: a coupling portion for feeding-in or feeding-out signals;a first radiation portion coupled to one end of the coupling portion; the first radiation portion bended at one or more bending points to form a plurality of sections, and at least two sections distributed on two planes that are not parallel to each other; anda second radiation portion coupled to another end of the coupling portion; the second radiation portion comprising at least one section, wherein the at least one section of the second radiation portion is paralleled to at least one section of the first radiation portion in order to have radiation characteristics of the two paralleled sections intercoupled for increasing a bandwidth of the multi-band antenna.

2. The multi-band antenna of claim 1 wherein a given section of the second radiation portion is paralleled to a terminal section of the first radiation portion to have radiation characteristics of the given section and the terminal section intercoupled; the terminal section is a section of the first radiation portion extended the furthest from the coupling portion.

3. The multi-band antenna of claim 2 wherein a distance between the given section of the second radiation portion and the terminal section of the first radiation portion is smaller than a distance between the given section of the second radiation portion and any other section of the first radiation portion.

4. The multi-band antenna of claim 2 wherein the given section of the second radiation portion is paralleled to a terminal section of the second radiation portion to have radiation characteristics of the given section and the terminal section of the second radiation portion intercoupled; the terminal section of the second radiation portion is a section of the second radiation portion extended the furthest from the coupling portion.

5. The multi-band antenna of claim 2 wherein the second radiation portion is bended at one or more bending points to form a plurality of sections.

6. The multi-band antenna of claim 2 wherein some of the sections of the second radiation portion are on a same plane as the terminal section of the first radiation portion.

7. The multi-band antenna of claim 6 wherein at least one of the sections of the first radiation portion is on a different plane from all of the sections of the second radiation portion.

8. The multi-band antenna of claim 1 is a monopole antenna.

9. The multi-band antenna of claim 1 wherein the first radiation portion is used for radiating electromagnetic waves in low frequency bands, the second radiation portion is used for radiating electromagnetic waves in high frequency bands, so the multi-band antenna supports transmitting and receiving of multi-band wireless signals.

10. The multi-band antenna of claim 1 wherein the first radiation portion and the second radiation portion are formed with bended conductors having uniform cross sections.

11. The multi-band antenna of claim 1 further comprising a fixture which comprises a medium material for protecting a structure of the multi-band antenna or adjusting characteristics of the multi-band antenna.

12. The multi-band antenna of claim 11, wherein the fixture allows the antenna to be embedded on a circuit board so that different sections of the multi-band antenna are distributed on both sides of the circuit board.

13. A multi-band antenna comprising: a coupling portion used for receiving a feed-in or a feed-out of a signal;a first radiation portion coupled to one end of the coupling portion; the first radiation portion bended at one or more bending points to form a plurality of sections; anda second radiation portion coupled to another end of the coupling portion; the second radiation portion comprising at least one section, wherein the at least one section of the second radiation portion is paralleled to at least one section of the first radiation portion in order to have radiation characteristics of the two paralleled sections intercoupled for increasing a bandwidth of the multi-band antenna.

14. The multi-band antenna of claim 13 wherein a given section of the second radiation portion is paralleled to a terminal section of the first radiation portion to have radiation characteristics of the given section and the terminal section intercoupled; the terminal section is a section of the first radiation portion extended the furthest from the coupling portion.

15. The multi-band antenna of claim 14 wherein a distance between the given section of the second radiation portion and the terminal section of the first radiation portion is smaller than a distance between the given section of the second radiation portion and other sections of the first radiation portion.

16. The multi-band antenna of claim 14 wherein a terminal section of the second radiation portion is a section of the second radiation portion extended the furthest from the coupling portion.

17. The multi-band antenna of claim 14, wherein the first radiation portion is used for radiating electromagnetic waves in low frequency bands, the second radiation portion is used for radiating electromagnetic waves in high frequency bands, so the multi-band antenna supports transmitting and receiving of multi-band wireless signals.

18. The multi-band antenna of claim 13 further comprising a fixture that comprises a medium material used for protecting a structure of the multi-band antenna or adjusting characteristics of the multi-band antenna.

19. The multi-band antenna of claim 18 wherein the fixture allows the antenna to be embedded on a circuit board so that different sections of the multi-band antenna are distributed on both sides of the circuit board.

20. A multi-band antenna comprising: a coupling portion, used for receiving a feed-in or a feed-out of a signal;a first radiation portion coupled to one end of the coupling portion formed with bended conductors having uniform cross sections; the first radiation portion bended at one or more bending points to form a plurality of sections; anda second radiation portion coupled to another end of the coupling portion and formed with bended conductors having uniform cross sections; at least one of the sections of the second radiation portion is paralleled to at least one section of the first radiation portion in order to have the radiation characteristics of the two paralleled sections intercoupled for increasing a bandwidth of the multi-band antenna.