KR20100099076A - Ultra wide band monopole internal antenna - Google Patents

Abstract

PURPOSE: A multiband built-in antenna is provided to have a wideband property by using a coupling matching process when a multiband is designed. CONSTITUTION: An impedance matching/feeding part(704) is formed on a substrate and executes an impedance matching process and a power supplying process. A first radiation member is combined with the impedance matching/feeding part. A first matching member(720) is connected to the ground with a predetermined length. A second matching member(730) is arranged to be separated from the first matching member and is electrically connected to a feeding point. The distance between the first matching member and the second matching member partly varies. The first radiation member is extended from the first matching member and receives power by being connected to the second matching member.

Description

Multiband Internal Antenna {Ultra Wide Band Monopole Internal Antenna}

The present invention relates to an antenna, and more particularly to a multi-band internal antenna.

Recently, a mobile terminal has been required to have a small size and a light weight, and to receive a mobile communication service having a different frequency band using a single terminal. For example, CDMA services in the 824-894 MHz band commercially available in Korea, PCS services in the 1750-1870 MHz band, CDMA services in the 832-925 MHz band commercially available in Japan, and the 1850-1990 MHz band commercially available in the US. Multi-band signal as needed among mobile communication services using various frequency bands such as PCS service, GSM service of 880 ~ 960 MHz band commercialized in Europe, China, and DCS service of 1710 ~ 1880 MHz band commercialized in some parts of Europe. There is a need for a terminal that can simultaneously use.

In addition, there is a demand for a composite terminal that can use services such as Bluetooth, Zigbee, WLAN, and GPS. In order to use such a multi-band service, a multi-band antenna capable of operating in two or more bands desired should be used. In general, a helical antenna and a planar inverted antenna (PIFA) are mainly used as antennas of a mobile communication terminal.

/4 헬리컬 안테나로 동작한다. 이러한 안테나는 높은 이득을 얻을 수 있는 장점이 있으나, 무지향성으로 인해 전자파 인체 유해기준인 SAR 특성이 좋지 않다. 또한, 헬리컬 안테나는 단말기의 외부에 돌출된 모양으로 구성되므로, 단말기의 미적외관 및 휴대기능에 적합한 외관 설계가 어려운데, 이에 대한 내장형의 구조는 아직 연구된 바 없다. Here, the helical antenna is used together with the monopole antenna as an external antenna fixed to the top of the terminal. When the helical antenna and the monopole antenna are used together, the antenna operates as a monopole antenna when the antenna is extended from the terminal body, and when the antenna is retracted,

/ 4 Operates as a helical antenna. These antennas have the advantage of obtaining high gain, but due to their omni-directional, SAR characteristics, which are harmful to the human body of electromagnetic waves, are not good. In addition, since the helical antenna is configured to protrude to the outside of the terminal, it is difficult to design an appearance suitable for the aesthetics and the portable function of the terminal, but the internal structure thereof has not been studied yet.

In addition, the inverted-F antenna is an antenna designed to have a low profile structure to overcome this disadvantage. The inverted-F antenna improves SAR characteristics by reinforcing the beam directed toward the ground plane of the entire beams generated by the current induced in the radiator to a human body, thereby reinforcing the beam directed toward the radiator. The low profile structure can be realized by acting as a rectangular microstrip antenna having a directivity and the length of the rectangular flat radiating portion reduced by half.

Such an inverted-F antenna has a radiation characteristic having a directivity that attenuates the beam intensity in the human body direction and strengthens the beam intensity in the human body direction, so that the electromagnetic wave absorption rate is excellent when compared with a helical antenna. However, when the inverted-F antenna is designed to operate in multiple bands, there is a problem that the frequency bandwidth is narrow.

When the inverted-F antenna is designed to operate in multiple bands, the narrow frequency bandwidth is caused by point matching where a match is made at a specific point when matching with the radiator.

 There is a need for an antenna capable of overcoming narrow band characteristics, which is a disadvantage of the inverted-F antenna, while having a low profile structure for more stable operation in multiple bands.

In the present invention, in order to solve the problems of the prior art as described above, it is proposed a multi-band internal antenna having a broadband characteristics when designing a multi-band.

Another object of the present invention is to propose a multi-band internal antenna having broadband characteristics using matching by coupling.

It is a further object of the present invention to propose a multiband antenna which is less affected by external factors such as hand effects.

Other objects of the present invention may be derived by those skilled in the art through the following examples.

In order to achieve the above object, according to an aspect of the present invention, a substrate; An impedance matching / feeding unit formed on the substrate; A first radiating member coupled to the impedance matching / feeding part, wherein the impedance matching / feeding part has a predetermined length and is spaced apart from the first matching member having a predetermined length and a first matching member connected to ground; And a second matching member disposed and electrically connected to the feed point, wherein a separation distance between the first matching member and the second matching member is partially changed.

The first matching member and the second matching member perform impedance matching by coupling.

The first matching member is bent at least once, and the second matching member is bent in correspondence with the bent structure of the first matching member.

The first radiating member extends from the first matching member of the impedance matching / feeding part and is fed by a coupling from the second matching member.

The antenna may further include a second radiating member formed on the substrate and electrically connected to ground and fed by coupling from the second matching member of the impedance matching / feeding unit.

Meanwhile, according to another embodiment, the antenna may further include a second radiation member formed on the substrate and electrically coupled with the second matching member of the impedance matching / feeding unit to receive power.

According to another aspect of the invention, the substrate; An impedance matching / feeding unit formed on the substrate; A first radiating member coupled to the impedance matching / feeding part, wherein the impedance matching / feeding part has a predetermined length and is spaced apart from the first matching member having a predetermined length and a first matching member connected to ground; A second matching member disposed and electrically connected to a feed point, wherein at least one of the first matching member and the second matching member includes a plurality of coupling elements protruding from the first matching member or the second matching member; There is provided a multiband internal antenna comprising.

According to the present invention, there is an advantage in that it is possible to provide a multiband internal antenna having wideband characteristics by using coupling matching in a multiband design. In addition, according to the present invention, another object of the present invention is to provide a multi-band antenna less affected by external factors such as hand effects.

1 is a view showing the structure of a multi-band internal antenna according to a first embodiment of the present invention.
FIG. 2 shows S11 parameters of the antenna shown in FIG. 1; FIG.
3 is a diagram showing the structure of a multi band internal antenna according to a second embodiment of the present invention;
4 is a diagram illustrating S11 parameters of an antenna according to a second embodiment of the present invention.
5 is a diagram showing the structure of a multi band internal antenna according to a third embodiment of the present invention;
6 is a diagram illustrating S11 parameters of a multi band antenna according to the third embodiment of the present invention.
7 is a diagram illustrating a structure of a multi band internal antenna according to a fourth embodiment of the present invention.
8 illustrates S11 parameters of a multiband antenna according to the fourth embodiment of the present invention.
9 is a diagram illustrating a structure in which a multi band internal antenna according to a third embodiment of the present invention is coupled to an antenna carrier of a terminal.
10 is a diagram illustrating a structure in which a multi band internal antenna according to a fourth embodiment of the present invention is coupled to a PCB of a terminal;
11 to 13 illustrate structures of the radiation member and the ground member for securing a large coupling according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the multi-band internal antenna according to the present invention.

In the present embodiment, a multi-band antenna used for the GSM service band, the PCS service band, and the WCDMA service band will be described as an example. However, the multiband antenna of the present invention is not limited to the above-described band, and may operate as a multiband antenna for various frequency bands.

1 is a diagram illustrating a structure of a multi band internal antenna according to a first embodiment of the present invention.

Referring to FIG. 1, the multi band internal antenna according to the first exemplary embodiment of the present invention may include a substrate 100, a radiation member 102 and an impedance matching / feeding unit 104 formed on the substrate.

In FIG. 1, the substrate 100 is made of a dielectric material and functions as the body of the antenna to which other components are coupled. Various dielectric materials may be applied to the substrate 100. In one example, a PCB substrate or an FR4 substrate may be used as the substrate.

As described above, an antenna having a structure such as an inverted-F antenna has been point-matched with the radiating member by a shorting pin or the like. This point matching has a problem of narrowing the frequency bandwidth.

According to a preferred embodiment of the present invention, in order to solve the problem of point matching, a matching scheme by coupling is proposed, and an impedance matching / feeding unit 106 having a predetermined length is provided.

The impedance matching / feeding unit 104 includes a first matching member 120 electrically connected to a ground and a second matching member 130 electrically connected to a feed point (not shown). In the impedance matching / feeding unit 104, coupling feeding from the second matching member 130 to the first matching member 120 is performed, and the radiation member 102 electrically connected to the first matching member 120. At this point the radiation of the signal takes place.

The first matching member 120 and the second matching member 130 are formed at predetermined intervals, and coupling matching is performed by the interaction between the first matching member 120 and the second matching member. When the first matching member 120 and the second matching member 130 interact with each other, the capacitive component among the capacitive component and the inductive component acts as a more important element. A structure that provides impedance matching for is proposed.

In order to diversify the capacitive component, the spacing between the first matching member 120 and the second matching member 130 is partially changed.

In FIG. 1, as an example for partially changing the distance between the first matching member 120 and the second matching member 130, the first matching member 120 is bent over a plurality of second matching members 130. A correspondingly curved structure is shown.

Based on the bent point, the first matching member 120 is divided into three parts, and is divided into an A1-A1 'part, an A2-A2' part, and an A3-A3 'part. Meanwhile, the second matching member 130 is bent to correspond to the first matching member 120 and is divided into a B1-B1 'part, a B2-B2' part, and a B3-B3 'part.

According to a preferred embodiment of the present invention, the separation distance d1 between A1-A1 'part and B1-B1' part, the separation distance d2 between A2-A2 'part and B2-B2' part and A3-A3 The separation distance d3 between the 'part and the B3-B3' part is set differently.

That is, the first matching member 120 and the second matching member 130 are implemented in a bent structure and partially different from each other to satisfy the broadband characteristics due to coupling matching and feeding.

1 illustrates an embodiment in which the distance between the first matching member 120 and the second matching member 130 is partially changed by bending the first matching member 120 and the second matching member 130. It will be understood by those skilled in the art that this may be implemented in various forms in addition to the embodiment shown in FIG. 1.

For example, the second matching member 130 is formed in a straight line, and the first matching member 120, the radiation member is disposed in a diagonal line to vary the distance, in part, such as the radiation member 102 and the ground member 104 Various embodiments may be included in the scope of the present invention, such that the distance between the?

The radiating member 102 functions to receive an RF signal and radiate to the outside by the coupling feeding as described above. The radiating member 102 is connected from the first matching member 120 of the impedance matching / feeding section 104. In this case, the radiation frequency band may be set by the length of the radiation member 102 and the length of the impedance matching / feeding unit 104.

FIG. 2 is a diagram illustrating S11 parameters of the antenna illustrated in FIG. 1.

Referring to FIG. 2, it can be seen that the S11 parameter of the antenna shown in FIG. 1 exhibits relatively wideband characteristics.

In order to obtain higher broadband characteristics when matching by coupling is desired, a structure in which a large capacitive component value is obtained in a specific region along with the diversification of the capacitive component is preferable. In addition, when a large capacitive component is present, a large capacitance value may be less affected by external factors such as a hand effect.

3 is a diagram illustrating a structure of a multi band internal antenna according to a second embodiment of the present invention.

Referring to FIG. 3, the multi band internal antenna according to the second exemplary embodiment of the present invention includes a substrate 300, a radiation member 302 and an impedance matching / feeding unit 304 formed on the substrate 300. The impedance matching unit 304 may include a first matching member 320 and a second matching member 330.

In addition, a plurality of first coupling elements 306 are formed to protrude perpendicularly to the longitudinal direction of the first matching member 320, and a plurality of second coupling elements perpendicular to the longitudinal direction of the second matching member. 308 is formed to protrude.

As in the first embodiment described above, the first matching member 320 is electrically connected to the ground, the second matching member 330 is electrically connected to the feed point, and the feeding is performed at the second matching member 330. Feeding by a coupling is performed to the first matching member 320.

 The multi-band internal antenna according to the second embodiment of the present invention shown in FIG. 3 is structured to allow coupling by higher capacitive components.

The built-in antenna according to the second embodiment of the present invention has a structure in which a first coupling element 306 and a second coupling element 308 are added to the antenna structure according to the first embodiment.

The first coupling element 306 and the second coupling element 308 allow for coupling matching by larger capacitive components.

As shown in FIG. 3, the first coupling element 306 and the second coupling element 308 protrude from the first matching member and the second matching member in the form of a comb. Preferably, the first coupling element 306 and the second coupling element 308 are formed in a comb tooth shape and intersecting with each other.

Such coupling elements 306 and 308 can substantially close the distance between the first matching member and the second matching member to enable acquisition of larger capacitive components as well as contribute to the diversification of the capacitive components. This allows for more broadband matching.

4 is a diagram illustrating S11 parameters of an antenna according to a second embodiment of the present invention.

Referring to FIG. 4, it can be seen that the antenna according to the second embodiment has better broadband characteristics than the antenna of the first embodiment shown in FIG. 2.

The structure for securing a larger coupling between the radiating member and the ground member can be implemented in various ways in addition to the structures shown in FIGS. 1 and 3. 11 to 13 are diagrams illustrating structures of a first matching member and a second matching member for securing a large coupling according to an embodiment of the present invention.

11 to 13, the width and length of the coupling element may be set to vary, and the coupling element may be implemented in a non-rectangular shape as shown in FIG. 13.

5 is a diagram illustrating a structure of a multi band internal antenna according to a third embodiment of the present invention.

Referring to FIG. 5, the multi-band internal antenna according to the third exemplary embodiment of the present invention includes a substrate 500, a first radiating member 502 and an impedance matching / feeding unit 504 formed on the substrate 500. And a second radiating member 506.

The impedance matching / feeding unit 504 includes a first matching member 520 electrically connected to the ground and a second matching member 530 electrically connected to the feed point, and the first matching member 520 and the first matching member 520. In the second matching member, coupling elements 306 and 308 are formed to protrude to allow for more broadband matching.

The first radiating member 502 extends from the first matching member 520 and is fed by a coupling.

In the third embodiment, the configuration of the first radiation member 502 and the impedance matching unit 504 is the same as in the above-described second embodiment, and the second radiation member 506 is additionally provided. The second radiating member 506 is additionally provided to transmit and receive a signal of a different band from the first radiating member 502.

The second radiating member 506 is spaced apart from the first radiating member 502 and the impedance matching / feeding unit 504 by a predetermined distance to be in electrical contact with each other. The second radiating member 506 is electrically connected to the ground, and power feeding is supplied by coupling from the impedance matching / feeding unit 504.

In FIG. 5, a case in which the second radiating member 506 is shorter than that of the first radiating member 502 is illustrated, and the second radiating member 506 is capable of receiving a signal having a high frequency band compared to the first radiating member 502. It is provided to transmit and receive.

Although the second radiating member 506 is illustrated in FIG. 5 once bent, it will be apparent to those skilled in the art that the shape of the second radiating member is not limited thereto.

It will be understood by those skilled in the art that the method of additionally including the radiating member for forming resonance points in other bands is applicable to the first embodiment as well as the second embodiment.

6 is a diagram illustrating S11 parameters of a multi band antenna according to the third embodiment of the present invention.

Referring to FIG. 6, it may be confirmed that the resonance point is formed in the high frequency band by additionally providing the second ground member 510. Two resonance points are formed in the high frequency band, and the additional resonance point is due to parasitic components.

7 is a diagram illustrating a structure of a multi band internal antenna according to a fourth embodiment of the present invention.

Referring to FIG. 7, a multi band internal antenna according to a fourth exemplary embodiment of the present invention is formed on a substrate 700, a first radiating member 702 formed on the substrate 700, and the substrate 700. The impedance matching / feeding unit 704, and the second radiating member 706.

The impedance matching / feeding unit 704 includes a first matching member 720 and a second matching member 730, the first matching member 720 being electrically connected to ground, and the second matching member 730. Is electrically connected to the feed point.

As in the second and third embodiments, the first radiating member receives the RF signal through coupling feeding at the impedance matching / feeding unit.

In the fourth embodiment, as compared with the third embodiment, the second radiating member 706 is not fed by the coupling and is fed directly. The second radiating member 706 is electrically coupled with the second matching member 730 of the impedance matching / feeding unit 704 that is electrically connected to the feeding point to perform direct feeding.

As such, when the radiation member is additionally provided for transmission and reception of signals in other bands, the radiation member may be fed by the coupler as in the third embodiment, and as in the fourth embodiment, direct feeding may be performed. It may be.

7 illustrates a case in which the second matching member 730 and the second radiating member 706 are electrically coupled on the substrate, but the second matching member 730 and the second radiating member 706 are necessarily coupled on the substrate. Need not be and may be electrically coupled in other areas.

In addition, it will be apparent to those skilled in the art that the manner in which the resonance point is formed in another band by adding the radiation member can be applied to the first embodiment as well as the second embodiment.

8 is a diagram illustrating S11 parameters of a multi-band antenna according to the fourth embodiment of the present invention.

Referring to FIG. 8, it can be seen that a resonance point is additionally formed in the high frequency band. On the other hand, unlike the third embodiment of Figure 6 it can be seen that no additional resonance point is formed by the parasitic component.

9 is a diagram illustrating a structure in which a multi band internal antenna according to a third embodiment of the present invention is coupled to an antenna carrier of a terminal.

The antenna carrier includes a horizontal portion 900 and a vertical portion 902, the vertical portion 902 is formed perpendicular to the substrate 910 of the terminal to support the horizontal portion 900, the horizontal portion 900 It is formed parallel to the substrate of the terminal, the above-described elements are coupled to the horizontal portion 900.

In FIG. 9, the first matching member extends to the vertical portion 902 to be coupled to the ground of the terminal substrate 910, and the second matching member extends to be electrically connected to the feed point. In addition, when the second radiation member is provided, the second radiation member is extended to the vertical portion 902 to be coupled to the ground of the terminal substrate 910.

10 is a diagram illustrating a structure in which a multi band internal antenna according to a fourth embodiment of the present invention is coupled to a PCB of a terminal.

Referring to FIG. 10, the second radiating member and the second matching member connected to the feed point of the fourth embodiment are electrically coupled at a point A, and the second radiating member is directly fed with power.

Claims (5)

Board;
An impedance matching / feeding unit formed on the substrate to perform impedance matching and feeding;
A first radiating member coupled to the impedance matching / feeding part,
The impedance matching / feeding unit includes a first matching member having a predetermined length and connected to ground, and a second matching member disposed to be spaced apart from the first matching member and having a predetermined length and electrically connected to a feed point.
The separation distance between the first matching member and the second matching member is partially changed, and the first radiating member extends from the first matching member and is fed by a coupling from the second matching member. Multiband internal antenna. The method of claim 1,
And the first matching member and the second matching member perform impedance matching by coupling. The method of claim 1,
And the first matching member is bent at least once, and the second matching member is bent in correspondence with the bent structure of the first matching member. The method of claim 1,
And a second radiating member formed on the substrate and electrically connected to ground, the second radiating member being fed by a coupling from the second matching member of the impedance matching / feeding unit. The method of claim 4, wherein
And a second radiating member formed on the substrate and electrically coupled with the second matching member of the impedance matching / feeding part to receive power.

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