KR20090111056A - Multiband Antenna of Portable Device and Portable Device Using the Same - Google Patents

Abstract

Disclosed is a multi-band internal antenna capable of securing a wide bandwidth by changing a configuration of a feeder. A built-in antenna used in a portable terminal, comprising: a feed terminal fed from a main board of a terminal through a feed line, a ground terminal grounded through a ground line to a ground portion of the terminal, and a first frequency resonance pattern resonating in a first frequency band And an antenna pattern portion including a second frequency resonance pattern resonating in a second frequency band higher than the first frequency and an antenna carrier portion to which the antenna pattern portion is fixed, wherein the feed terminal and the second feeding terminal of the antenna pattern portion A slot-shaped impedance matching part is provided between the frequency resonance patterns to form an internal antenna. Therefore, it is possible to easily configure a multi-band internal antenna that must support multiple bands by ensuring a wide bandwidth even in the internal antenna of the same volume, it is suitable for a multi-band mobile communication terminal.

Description

MULTI-BAND ANTENNA FOR PORTABLE DEVICE AND PORTABLE DEVICE USING THE SAME

The present invention relates to a multi-band antenna of a portable device, and more particularly, to a multi-band antenna having a configuration of a feeder capable of securing a wide bandwidth for two or more bands as an antenna mainly used in a mobile communication terminal. will be.

The development of antenna technology may also be an important factor in the slimming and miniaturization of mobile communication terminals and portable digital TV (eg, DMB, DVB-H, MediaFlo) terminals, which are becoming more common.

For example, the conventional first generation mobile communication terminals are equipped with a stud type antenna, and have a protruding exterior at one side of the upper end of the mobile communication terminal, which is inconvenient to carry and has a high risk of damage. There was a problem that the degree of freedom of design which greatly affects the commerciality was limited.

In recent years, however, an intena type has been generally adopted in which an antenna is mounted in a housing of a terminal and a protruding antenna is not exposed in appearance.

In order to meet the design trend of slim and miniaturized mobile communication terminals, such built-in antennas are required to have excellent radiation characteristics and wide bandwidth even in a small volume. In particular, in the case of the built-in antenna, the antenna space that can be mounted in the entire mobile communication terminal is becoming more and more narrow. Therefore, it is necessary to obtain excellent characteristics within the range that does not change the size of the entire antenna. It's a big issue for you.

In addition, most recent terminals have to accommodate two or three or more bands. For example, in the case of a mobile communication terminal that complies with the Wide-band Code Division Multiple Access (WCDMA) technology of the 3GPP standard, which is widely used worldwide as a representative of the third generation mobile communication, in most cases, the GSM frequency band ( 860 to 960 MHz), Universal Mobile Telecommnunications System (UMTS) band (1,920 to 2,170 MHz), and additionally, Global Positioning System (DCS) band (1,710 to 1,880 MHz) and PCS (Personal Communication Service) band (1,880 to 1,990) MHz) shall be supported.

As such a method for supporting multiple bands with a single antenna, a method of forming a transmitting / receiving radiator into a multilayer structure and a method of forming a pattern on a single radiator to implement double resonance may be used. A method that can be used as a process and a low cost is a method for forming a double resonance by forming a pattern on a single radiator. However, this method has a problem that it is difficult to obtain a wide reception bandwidth.

An object of the present invention for solving the above problems is to provide a built-in multi-band antenna for a portable terminal that can obtain a wide impedance bandwidth in a high frequency band by improving the structure of the feeder.

Another object of the present invention for solving the above problems is to provide a portable device using an embedded multi-band antenna that can obtain a wide impedance bandwidth in a high frequency band by improving the structure of the feeder.

In order to achieve the above object, the present invention provides a built-in antenna for a portable terminal, comprising: a feed terminal fed from a main board of a terminal through a feed line, a ground terminal grounded through a ground line to a ground portion of the terminal, Double resonance including an antenna pattern portion including a first frequency resonance pattern resonating in one frequency band and a second frequency resonance pattern resonating in a second frequency band higher than the first frequency and an antenna carrier portion to which the antenna pattern portion is fixed And an antenna, and an impedance matching part having a slot shape is provided between the power supply terminal and the second frequency resonance pattern of the antenna pattern part.

The antenna carrier part may be made of polycarbonate (PC) and the antenna pattern part may be made of a conductive metal material.

Here, the slot shape of the impedance matching portion may have a capacitive load and may be configured to extend the bandwidth of the second frequency resonance pattern through impedance matching between the feed terminal and the second frequency resonance pattern.

The present invention for achieving the above object, there is provided a portable device having the built-in antenna.

The portable device may be a mobile communication terminal having a built-in antenna, wherein the first frequency band is a band including 860 MHz to 960 MHz, and the second frequency band is a band including 1,710 MHz and 2,170 MHz.

When using the built-in antenna according to the present invention as described above, it is possible to secure a wider bandwidth by modifying the feeder configuration as compared to the conventional built-in antenna.

In addition, in the case of using the built-in antenna according to the present invention, it is possible to secure a wide bandwidth only by changing the configuration of the feeder, and it is not necessary to separately change the material of the antenna carrier or the volume of the antenna pattern part to increase the bandwidth. That is, it is possible to form an antenna having a wide bandwidth only by the configuration of the feeder can be used suitably for the recent portable terminal, especially mobile communication terminal that must support multiple bands.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In describing the drawings, similar reference numerals are used for similar elements.

Terms such as first, second, A, and B may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described in the specification, and one or more other It is to be understood that the present invention does not exclude the possibility of the presence or the addition of features, numbers, steps, operations, components, parts, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1A to 1C and 2 are conceptual diagrams for explaining the structure of a multi-band antenna according to the present invention.

First, FIG. 1A is a top view of a multi band antenna according to the present invention, FIG. 1B is a front view of a multi band antenna according to the present invention, and FIG. 1C is a rear view of a multi band antenna according to the present invention.

2 is a perspective view of a multi band antenna according to the present invention.

Hereinafter, a basic structure of a multi band antenna according to the present invention will be described with reference to FIGS. 1A to 1C and FIG. 2.

The multi band antenna according to the present invention may include an antenna pattern part 110 and an antenna carrier part 120 to which the antenna pattern part 110 is fixed.

In this case, the antenna carrier part 120 may be made of a high dielectric material, and the antenna pattern part 110 may be made of a conductive metal material. For example, the antenna carrier unit 120 may be formed of a synthetic resin material such as poly-carbonate (PC) or the like by injection molding. The antenna carrier part 120 is installed to be spaced apart from the printed circuit board mounted inside the terminal while the antenna pattern part 110 is fixed to support the antenna pattern part 110.

A plurality of fastening holes 111 are formed in the antenna pattern part 110, and a plurality of fastening protrusions 121 are formed in the antenna carrier part 120, and the fastening protrusions 111 and the fastening holes are formed. The antenna pattern part 110 is coupled to the antenna carrier part 120 by the combination of the fields 121. In addition, after coupling the fastening holes 111 and the fastening protrusions 121, the antenna pattern part 110 may be fixed to the antenna carrier part 120 by heat fusion molding.

As shown in FIGS. 1A to 1C and 2, the antenna pattern unit 110 is bent to form a multi-band antenna having a shape fixed to the top, front, and rear surfaces of the antenna carrier 120. In addition, the antenna pattern part 110 has a feed terminal 112 fed by a feed line from a printed circuit board of the terminal, a ground terminal 113 grounded by a ground line grounded to a ground portion of the terminal, and a first frequency. A first frequency resonance pattern resonating in a band and a second frequency resonance pattern resonating in a second frequency band higher than the first frequency are included.

Hereinafter, the shape of the antenna pattern portion 110 shown in an unfolded unfolded form will be described in more detail.

3A and 3B are conceptual views illustrating an antenna pattern unit for explaining a structure of a feeding unit of a multi-band antenna according to the present invention.

3A and 3B are conceptual views provided to illustrate the shape of the antenna pattern part 110 fixed to the antenna carrier part 120 described with reference to FIGS. 1A to 1C and 2, and the case of FIG. 3A is conventional. An example of an antenna pattern of a multi band antenna according to the technology is illustrated, and FIG. 3B illustrates an example of an antenna pattern of a multi band antenna according to the present invention. That is, FIGS. 2A and 2B illustrate the antenna pattern portion 110 having a flattened shape before being bent to be fixed to the antenna carrier portion 120.

In addition, the numerical values of the first frequency band in the GSM band, the second frequency band in the UMTS (Universal Mobile Telecommnunications System) band (1,920 to 2,170 MHz), the Global Positioning System (DCS) band (1,710 to 1,880 MHz) and PCS ( Personal Communication Service) It is assumed that the band (1,880 ~ 1,990MHz) is set to the comprehensive band. It is the numerical value in millimeters. For example, the antenna pattern portion illustrated in FIGS. 3A and 3B has a volume of 29.2 mm × 8.2 mm × 8.3 mm in a bent state.

First, in both cases of FIGS. 3A and 3B, the pattern portion 310 resonating in a low band and the pattern portion 320 resonating in a high band exist together. Able to know. That is, the first frequency resonance pattern 310 is a pattern formed to have a length corresponding to the first frequency band, and the second frequency resonance pattern 320 has a length corresponding to a second frequency band higher than the first frequency. It is a pattern formed to have.

Next, the feed terminal 112 is electrically connected to a printed circuit board (PCB) mounted inside the terminal to form a first frequency resonance pattern 310 and a second frequency formed in the antenna pattern unit 110. A terminal for transmitting a signal to the resonance pattern 320, the ground terminal 113 is connected to the ground layer of the printed circuit board mounted on the terminal or connected to the ground region inside the terminal to the first frequency resonance pattern 310 And a terminal for grounding the current of the second frequency resonance pattern 320.

The antenna pattern part 110 of the multi-band antenna illustrated in FIGS. 3A and 3B is electrically connected directly to the printed circuit board or the ground area of the portable terminal by the feed terminal 112 and the ground terminal 113. That is, a signal is applied through the power supply terminal 112 of the antenna pattern unit 110, and a current applied to the power supply terminal 112 turns the first frequency resonance pattern 310 and the second frequency resonance pattern 320 to ground. The terminal 113 is returned.

At this time, the antenna pattern portion 110 has a shape that typically includes several slits, whereby the current applied to the antenna pattern portion 110 flows along a plurality of current paths. The resonance frequency band is determined according to the electrical length of each current path, and by varying the length of the current path, resonance in multiple bands is possible.

That is, the built-in antenna illustrated in FIGS. 3A and 3B may be described as a structure inducing resonance of a dual band by adjusting an electrical length of a current path by adjusting a shape of an antenna pattern part which is a radiator.

At this time, when comparing the shape of the antenna pattern portion illustrated in Figures 3a and 3b, in the antenna pattern portion of the conventional structure illustrated in Figure 3a the feed terminal 112 and the first and second frequency resonant patterns (310, 320) simply Unlike the connection, the antenna pattern portion according to the present invention illustrated in FIG. 3B has a slot shape 330 between the feed terminal 112 and the first and second frequency resonance patterns 310 and 320; feeding structure) is added.

At this time, between the feed terminal 112 and the first and second frequency resonance patterns 310 and 320 are added

The predetermined slot shape is a component provided to improve the bandwidth, which is an object of the present invention, and has a capacitive load, and through the impedance matching between the feed line and the first and second frequency resonance patterns 310 and 320, It serves to extend the bandwidth of the two frequency resonance pattern 320.

4 is an equivalent circuit diagram for explaining the effect of the slot shape interposed between the slot feed terminal and the resonance pattern in accordance with the present invention.

Referring to FIG. 4, an equivalent circuit of the multi-band antenna radiator unit according to the present invention illustrated in FIG. 3B is illustrated, and the equivalent circuit unit 410 of the first frequency resonance pattern 310 and the second frequency resonance pattern 320 of FIG. Equivalent circuit portion 420 is illustrated, respectively.

Next, according to the present invention, an equivalent circuit unit 430 according to a feeder provided with a slot shape is disclosed.

Here, the inductance parasitic load 431 is a load that can also be obtained by the feeder configuration of the conventional antenna radiator portion illustrated in FIG. 3A, but the capacitive parasitic load 432 is It is a capacitive load that can be obtained by the feeding part configuration of the antenna radiator part according to the present invention illustrated in Fig. 3b.

That is, the slot shape of the feeder provides a capacitive load between the feeder terminal 112 and the second frequency radiation pattern 320 and expands the bandwidth of the second frequency radiation pattern through impedance matching. It can be described as. Alternatively, the capacitive parasitic load 432 due to the slot shape of the feeder cancels the inductive parasitic load 431 and lowers the reactance component of the feeder by resonance, thereby adjusting the first through impedance matching. It can be explained by extending the bandwidth of the two frequency radiation pattern.

FIG. 5 is a graph of standing voltage ratios (VSWRs) for explaining bandwidth expansion of a multi-band antenna according to the present invention.

Typically, standing wave ratio of 2 or less for single band antenna, standing wave ratio of 3 or less for double band antenna, and standing wave ratio of 4 or less for triple band antenna are required. do. The antenna pattern portion illustrated in FIG. 3B is an antenna pattern portion for an antenna corresponding to the GSM band of the 900 MHz band and the DCS / PCS / UMTS band covering the 1,710 MHz to 2,170 MHz band, and can be largely treated as a dual band antenna. There will be.

Accordingly, if the antenna pattern part illustrated in FIG. 3B is taken as an example, a bandwidth having a standing wave ratio of 3 or less may be recognized as a bandwidth of the corresponding antenna, and FIG. 5 includes the antenna pattern part of the prior art illustrated in FIG. 3A. A built-in antenna having a built-in antenna and an antenna pattern part according to the present invention illustrated in FIG. 3B illustrates a standing wave ratio graph for each.

Referring to FIG. 5, in the case of a built-in antenna having an antenna pattern part of the related art, the high frequency band has a bandwidth (16.92%) of 1.688 GHz to 2.00 GHz, but in the case of a dual band antenna having an antenna radiator part according to the present invention. In the high frequency band, it has a bandwidth (33.49%) of 1.688GHz to 2.367GHz. That is, in the case of a built-in antenna having a feeder configuration according to the present invention, the effect of bandwidth expansion can be obtained by only modifying the feeder configuration in the same volume.

Meanwhile, in the above-described embodiment, a dual resonance built-in antenna for accommodating the GSM band (860 to 960 MHz) and the DCS / PCS / UMTS band (1,710 to 2,170 MHz) has been described as an example. However, the support band of the built-in antenna using the feeder configuration according to the present invention is not limited to the case of the above-described embodiment, for example, a dual band simultaneously supporting the DMB broadcast band, the WCDMA frequency band, the DMB broadcast band and the GSM frequency band. The antenna may also be variously applied.

That is, while the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be able to vary the present invention without departing from the spirit and scope of the invention described in the claims below. It will be appreciated that modifications and variations can be made.

1A is a top view of a multi band antenna according to the present invention, FIG. 1B is a front view of a multi band antenna according to the present invention, and FIG. 1C is a rear view of a multi band antenna according to the present invention.

2 is a perspective view for explaining the structure of a multi-band antenna according to the present invention.

3A and 3B are conceptual views illustrating an antenna pattern unit for explaining a structure of a feeding unit of a multi-band antenna according to the present invention.

4 is an equivalent circuit diagram for explaining the effect of the slot shape interposed between the slot feed terminal and the resonance pattern in accordance with the present invention.

5 is a graph of standing wave ratio (VSWR) for each frequency for explaining the bandwidth extension of a multi-band antenna according to the present invention.

<Explanation of symbols for the main parts of the drawings>

110: antenna pattern portion

111: power supply terminal 112: ground terminal

120: antenna carrier

310: first frequency resonance pattern

320: second frequency resonance pattern

Claims (5)

In the built-in antenna used for the portable terminal, A feed terminal fed from a main board of the terminal through a feed line, a ground terminal grounded through a ground line to a ground portion of the terminal, a first frequency resonance pattern resonating in a first frequency band, and a second higher than the first frequency An antenna pattern unit including a second frequency resonance pattern resonating in a frequency band; And A dual resonant antenna is configured to include an antenna carrier part to which the antenna pattern part is fixed; And a slot-shaped impedance matching portion between the feed terminal and the second frequency resonance pattern of the antenna pattern portion. The method of claim 1, The antenna carrier portion is a polycarbonate (PC: Poly-Carbonate) material, and the antenna pattern portion is a built-in antenna, characterized in that made of a conductive metal material. The method of claim 1, And the slot shape of the impedance matching part has a capacitive load to extend the bandwidth of the second frequency radiation pattern through impedance matching between the feed terminal and the second frequency resonance pattern. A portable device having the built-in antenna according to claim 1. The method of claim 4, wherein The portable device is a portable device comprising a mobile communication terminal having a built-in antenna, the first frequency band is a band containing 860MHz to 960MHz, the second frequency band is a band including 1,710MHz to 2,170MHz.

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