KR101765558B1 - Multiband internal antenna for mobile handset - Google Patents

Abstract

According to an embodiment of the present invention, a multiband internal antenna for a mobile communication terminal comprises: a patch type antenna having a slot formed therein; and a monopole type antenna coupled to the patch type antenna. The patch type antenna includes a branch for transmitting and receiving a signal in a predetermined band, thereby transmitting and receiving multiband signals with one antenna, and minimizing required costs and spaces for the antenna.

Description

[0001] MULTIBAND INTERNAL ANTENNA FOR MOBILE HANDSET [

The present invention relates to an antenna, and more particularly, to a built-in multiband antenna for a mobile communication terminal.

With the rapid development of wireless communication systems, multi-band antennas have become one of the most important issues and have attracted much attention. Most modern wireless capable devices require a low cost, lightweight dual or multiband antenna that is easy to manufacture and integrates with RF devices.

For mobile telephones, planar antennas are very attractive because they have a low profile and can be easily fabricated on a mobile phone's system circuit board for practical applications. Recently, many planar antennas with multi-band capability have been proposed, including multi-band planar P-F (PIFA) antennas and planar monopole antennas.

The planar antennas are easy to manufacture and low cost and can be easily integrated into printed circuit boards of notebook computers, mobile terminals, and other wireless networking devices. The planar monopole antenna has even attracted the most attention in Ultra-Wide-Band (UWB).

It is well known that the resonant frequency band of an antenna moves as the environmental conditions change. Therefore, a sufficient margin for the resonant bandwidth is always required, and most multi-band antennas exhibit a narrow bandwidth for the lowest frequency band. And the lowest frequency band is very difficult to broaden the bandwidth. One approach is to design a multi-band antenna with multiple branches, with each branch for the corresponding frequency bands. The longest branch sends and receives signals in the lowest frequency band.

For mobile phones or devices, it is the most difficult to obtain suitable performance in the lowest frequency band when designing the antenna. The more and more the service frequency is lowered, the more difficult it is to design the antenna within a limited space. Obtaining suitable performance in the high frequency band is relatively easy to achieve. And acquiring more service bands with a single antenna is another challenging task. And if one antenna can cover multiple services, the cost and space required for the antennas can be minimized.

Accordingly, a built-in multiband antenna for a mobile communication terminal capable of transmitting and receiving signals of multiple bands with a single antenna and minimizing the cost and space required for the antenna is required.

KR 10-0997895 b1

SUMMARY OF THE INVENTION It is an object of the present invention to provide a built-in multiband antenna for a mobile communication terminal capable of transmitting and receiving signals of multiple bands with one antenna and minimizing cost and space required for the antenna.

According to an aspect of the present invention, there is provided an embedded multi-band antenna for a mobile communication terminal,

A patch antenna having a slot formed therein; And

And a monopole antenna coupled to the patch antenna,

The patch antenna includes a branch for transmitting and receiving a signal of a predetermined band.

In the built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention, the patch antenna includes a first radiator having no slot formed therein and a second radiator having a slot formed therein, A branch for transmitting and receiving a signal may be formed in the second radiation portion.

In the built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention, the first radiation part and a part of the second radiation part transmit / receive a low-band signal, and another part of the second radiation part The monopole antenna transmits and receives a signal of a predetermined band, and the monopole antenna can transmit and receive a signal of a high band.

In addition, in the built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention, the second radiation portion and the monopole antenna may be formed on the same plane at a predetermined distance.

Further, in the built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention, the first radiating part may further include a first line having a predetermined length and a predetermined width, And the other end may be connected to the first radiation portion.

Further, in the built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention, the first line may include a first edge of a surface on which the monopole antenna is formed, An edge, and a first edge of a surface perpendicular to the surface on which the second radiating part is formed and facing the surface on which the monopole antenna is formed.

In the built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention, a portion of the first radiation portion excluding the first line may be a surface facing the surface on which the second radiation portion is formed, 2 radiating part may be formed on a plane perpendicular to the plane on which the radiating part is formed.

Further, in the built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention, the second radiating part may include a first radiating part having a shape determined by the shape of the slot and having a first end connected to a predetermined part of the first line And a second line connected at one end to the other end of the first pattern.

Also, in the built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention, the branch may be formed in a direction perpendicular to the first line along a corner of a surface on which the second radiation portion is formed.

Further, in the built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention, the monopole antenna is connected to a feeding point through a predetermined connection line, And may be formed in a direction perpendicular to the first line.

According to an embodiment of the present invention, a built-in multi-band antenna for a mobile communication terminal can transmit and receive signals of multiple bands with one antenna, and the cost and space required for the antenna can be minimized.

FIG. 1A is a top view and a side view of a built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention. FIG.
FIG. 1B is a view illustrating a structure of a built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention. FIG.
2A to 2I are diagrams showing a current distribution of a built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention.
3A-3I illustrate simulated 3D radiation patterns of a built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention.
4 is a photograph of an antenna implementing a built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention.
5 is a diagram showing the simulated S ₁₁ and S ₁₁ measured on the integrated multi-band antenna for the mobile communication terminal according to one embodiment of the present invention.
Figures 6A-6I illustrate normalized and measured radiation patterns of an implemented antenna.

BRIEF DESCRIPTION OF THE DRAWINGS The objectives, specific advantages and novel features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG.

Prior to that, terms and words used in the present specification and claims should not be construed in a conventional and dictionary sense, and the inventor may properly define the concept of the term in order to best explain its invention Should be construed in accordance with the principles and the meanings and concepts consistent with the technical idea of the present invention.

It should be noted that, in the present specification, the reference numerals are added to the constituent elements of the drawings, and the same constituent elements are assigned the same number as much as possible even if they are displayed on different drawings.

Also, the terms "first", "second", "one side", "other side", etc. are used to distinguish one element from another, It is not.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description of the present invention, a detailed description of known arts which may unnecessarily obscure the gist of the present invention will be omitted.

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

With the rapid changes in technology, people want to include more functionality in a single device. Moreover, countries need to design multi-band antennas for mobile phones because they use different frequency bands for traffic services and roaming is required when traveling abroad.

According to an embodiment of the present invention, an embedded multi-band antenna for a mobile communication terminal that can be used in a mobile device is provided. A built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention has a volume of 50 mm (W) x 21 mm (L) x 5 mm (H) × 100 mm (L), and can transmit and receive signals in nine service frequency bands including the LTE band with a VSWR (standing wave ratio) of less than 3.

Accordingly, the built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention can cover a plurality of services with one antenna, and the cost and space required for the antenna can be minimized.

Specifically, the built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention can transmit and receive signals of nine service frequency bands starting from the lowest frequency band (LTE: 699-798 MHz) in the LTE 700 have.

According to one embodiment of the present invention, the LTE 700, the PCS / K-PCS (Personal Communications Service / Korea-Personal Communications Service: 1750-1870 MHz), the US-PCS Communications Service: 1850-1990 MHz), UMTS / WCDMA (Wideband Code Division Multiple Access: 1920-2170 MHz), Wibro (2300-2390 MHz), LTE2300 (2300-2400 MHz), Bluetooth (2400- 2483 MHz) and WLAN (Wireless Local Area Network: 2400-2483.5 MHz), US-WiMAX (US Worldwide Interoperability for Microwave Access: 2400-2590 MHz), and LTE 2500 (2496-2690 MHz) An embedded multi-band antenna is provided.

The measured results of the fabricated antenna are verified by simulation results, and the simulation results were obtained using Ansoft 's High Frequency Structure Simulator (HFSS).

1A and 1B illustrate a geometric structure of a built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention. The antenna 130 of FIG. 1A is a final antenna completed by folding along the folding line of the antenna 150 of FIG. 1B.

The size of the antenna 130 is 50 mm (W) x 21 mm (L) x 5 mm (H). The size of the ground plane 140 is 60 mm (W) x 100 mm (L). The ground plane 140 is a copper sheet on an inexpensive FR4 substrate having a dielectric constant of 4.4 and a thickness of 1.6 mm. A 50 ohm coaxial cable was used to feed the antenna.

The built-in multiband antennas 130 and 150 for a mobile communication terminal according to an embodiment of the present invention include a patch antenna 104 having slots 110 formed therein and a monopole antenna 104 coupled to the patch antenna 104. [ (106).

The patch antenna 104 includes a branch 108 for transmitting and receiving a signal of a predetermined band.

The patch type antenna 104 includes a first radiation part 100 having no slot and a second radiation part 102 having a slot 110 formed therein and is connected to a branch branch 108 is formed in the second radiation part 102. [

A part of the first radiation unit 100 and the second radiation unit 102 transmit and receive a low band signal and the other part of the second radiation unit 102 transmits and receives a signal of a certain band, Type antenna 106 transmits and receives a high-band signal.

The second radiation part 102 and the monopole antenna 106 are formed on the same plane at a predetermined distance.

The first radiation unit 100 further includes a first line 118 having a predetermined length and a predetermined width. One end of the first line 118 is connected to a feed point through a predetermined connection line 114 and 116a and the other end is connected to the first radiation unit 100. [

The first line 118 includes a first edge of a surface on which the monopole antenna 106 is formed and a first edge of a surface on which the second radiation part 102 is formed and a second edge of the second radiation part 102, And is formed along a first edge of a surface facing the surface on which the monopole antenna 106 is formed.

A portion 119 of the first radiation portion 100 excluding the first line 118 is formed on a surface facing the surface on which the second radiation portion 102 is formed and a surface on which the second radiation portion 102 is formed And is formed on a plane perpendicular to the plane.

The second radiation part 102 includes a first pattern 120 whose shape is determined by the shape of the slot and whose one end is connected to a predetermined part of the first line 118, And a second line 122 connected to the other end of the second line.

The branch 108 is formed in a direction perpendicular to the first line 118 along the edge of the surface on which the second radiation part 102 is formed.

The monopole antenna 106 is connected to the feed point 112 through predetermined connection lines 114 and 116b and is connected to the first line (not shown) along the corners opposite to the corners of the surface on which the branch 108 is formed. 118 in the vertical direction.

In order to analyze the proposed antenna in the design process of the built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention and to compare the simulation results with the experimental results, Ansoft Corporation based on the finite element method, (HFSS) was used.

Table 1 shows the values of the design parameters obtained through simulation.

parameter Length (mm) parameter Length (mm) L 100.0 W 60.0 L1 14.0 W1 50.0 L2 6.6 W2 46.0 L3 17.0 W3 2.0 L4 11.0 W4 16.0 L5 15.0 W5 14.0 L6 2.0 W6 37.0 L7 2.0 W7 21.0 L8 3.0 W8 8.0 L9 2.0 W9 2.0 L10 21.0 W10 10.0 L11 5.6 W11 46.0 L12 14.6 W12 10.0 L13 4.6 W13 32.0 L14 8.0 W14 29.0 L15 2.0 W15 33.0

A commercial program based on the finite element method, HFSS, was used to obtain suitable values of the parameters associated with the built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention and to characterize the antenna.

Figures 2A-2I illustrate the excited surface current distribution obtained from the HFSS simulation in the radiating element of the built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention at each frequency.

2A is a diagram showing a current distribution for identifying a main radiating element at a low band frequency of 748 MHz, and FIGS. 2B, 2C and 2D are graphs showing current distributions at 1810 MHz, 1920 MHz and 2045 MHz, Lt; RTI ID = 0.0 > a < / RTI > main radiating element.

2E to 2I are diagrams showing current distributions for confirming the main radiation elements at specific frequencies of 2345 MHz, 2350 MHz, 2442 MHz, 2495 MHz and 2595 MHz, respectively.

Referring to FIG. 2A, the first line 118 of the left path (P1 in FIG. 1B) and the first line 118 of the left path (P1 in FIG. 1B) are set with reference to the feeding point 112 of the built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention. And the first pattern 120 are the main radiating elements at 748 MHz.

Referring to FIGS. 2B to 2D, a first line 118, a branch 108, a first pattern 120, and a second line 120 of a built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention 122) are the main radiating elements in each frequency band.

Referring to Figs. 2E to 2I, it can be confirmed that the monopole antenna 106 from the right path P2 on the basis of the feeding point 112 is the main radiation element.

In particular, referring to FIG. 2I, it can be seen that the monopole antenna 106 from the right path P2 on the basis of the feeding point 112 plays a major role for 2595 MHz.

3A-3I illustrate simulated 3D radiation patterns at 748 MHz, 1810 MHz, 1920 MHz, 2045 MHz, 2345 MHz, 2350 MHz, 2442 MHz, 2495 MHz and 2595 MHz, respectively.

4 is a photograph of an antenna implementing a built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention.

FIG. 5 shows measurement and simulation results related to S ₁₁ of a built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention. The results show good agreement between measurements and simulations.

The implemented antennas are LTE700 (699-798 MHz), PCS / K-PCS (1750-1870 MHz), US-PCS (1850-1990 MHz), UMTS / WCDMA (1920-2170 MHz), Wibro (2300-2390 MHz) ), LTE2300 (2300-2400 MHz), Bluetooth (2400-2483 MHz), WLAN (2400-2483.5 MHz), US-WiMAX (2400-2590 MHz), and LTE2500 (2496-2690 MHz) Respectively.

Table 2 shows measurement results and simulation results related to a VSWR (Voltage Standing Wave Ratio) of a built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention.

Frequency band (MHz) Simulated VSWR Measured VSWR LTE700
(At 748) 2.210 1.766 PCS / k-PCS
(At 1810) 1.866 1.771 US-PCS
(At 1920) 1.917 1.378 UMTS / WCDMA
(At 2045) 1.398 1.616 Wibro
(At 2345) 2.447 2.090 LTE2300
(At 2350) 2.375 2.077 Bluetooth / WLAN
(At 2442) 1.841 1.856 US-WiMAX
(At 2495) 1.500 1.627 LTE2500
(From 2595) 1.204 1.446

From Table 2, it is possible to identify the VSWRs that are simulated and measured in each frequency band. The maximum and minimum values of the simulated standing wave ratio values are 2.447 in the Wibro band and 1.204 in the LTE2500 band, respectively. Also, the maximum and minimum values of the measured standing wave ratio values are 2.090 in the LTE2300 band and 1.378 in the US-PCS band, respectively.

6a-6i illustrate the normalized and measured co-polarization of an implemented antenna of an embedded multi-band antenna for a mobile communication terminal according to an embodiment of the present invention in the xy, zy and zx planes at respective center frequencies ) And cross-polarization radiation patterns.

6A is a normalized and measured radiation pattern of the implemented antenna at 748 MHz, FIG. 6B is a normalized and measured radiation pattern of the implemented antenna at 1810 MHz, FIG. 6C is the normalized and measured radiation pattern of the implemented antenna at 1920 MHz 6D is the normalized and measured radiation pattern of the implemented antenna at 2045 MHz, FIG. 6E is the normalized and measured radiation pattern of the implemented antenna at 2345 MHz, FIG. 6F is the normalized and measured radiation pattern of 2350 MHz 6g is the normalized and measured radiation pattern of the implemented antenna at 2442 MHz and Fig. 6h is the normalized and measured radiation pattern of the implemented antenna at 2495 MHz And Figure 6i is the normalized and measured radiation pattern of the implemented antenna at 2595 MHz.

The radiation patterns of the implemented antenna were measured in an anechoic chamber equipped with an HP 8510C network analyzer and a remote measurement system. Since the sharp deep in the radiation patterns is considered to cause call drop, the antenna should not have sharp bone in the radiation patterns.

It has been confirmed that the built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention has appropriate radiation patterns at all center frequencies.

Table 3 shows measurement results of the maximum peak gain and average gain of the implemented antenna.

Frequency band Peak gain (dB) Average gain (dBi) LTE700 1.30 -1.01 PCS / k-PCS 2.16 -1.36 US-PCS 2.90 -2.31 WCDMA 2.56 -2.09 Wibro 2.21 -2.14 LTE2300 2.44 -2.20 Bluetooth / WLAN 3.35 -2.58 US-WiMAX 3.05 -2.79 LTE2500 2.38 -3.03

From Table 3, the maximum peak gain, the minimum peak gain, and the average gain in each service can be known. The maximum peak gain and the minimum peak gain are 3.35 dBi in the Bluetooth / WLAN service band and 1.30 dBi in the LTE700 service band. The maximum and minimum average gains are -1.01 ㏈ i at LTE700 and -3.03 ㏈ i at LTE2500, respectively.

The built-in multiband antenna for a mobile communication terminal according to an embodiment of the present invention covers the LTE700, PCS / K-PCS, US-PCS, UMTS / WCDMA, Wibro, LTE2300, Bluetooth, WLAN, US / WiMAX and LTE2500 bands . The antenna has a volume of 50 mm (W) x 21 mm (L) x 5 mm (H), and the size of the ground plane is 60 mm (W) x 100 mm (L).

The built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention has a VSWR of less than 3 in all service bands and does not have a sharp bone in a radiation pattern. And the measured antenna gain is practically applicable. Therefore, the results of the built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention show proper performance characteristics.

The built-in multi-band antenna for a mobile communication terminal according to an embodiment of the present invention is applicable to various multi-band mobile devices.

According to an embodiment of the present invention, a built-in multi-band antenna for a mobile communication terminal can transmit and receive signals of multiple bands with one antenna, and the cost and space required for the antenna can be minimized.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It is clear that the present invention can be modified or improved.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

100: first radiation part 102: second radiation part
104: patch antenna 106: monopole antenna
108: Branch 110: Slot
112: feed point 114, 116a, 116b: connection line
118: my line 119: patch
120: first pattern 122: second line
130, 150: Built-in multiband antenna for mobile communication terminal
140: ground plane

Claims (10)

A patch antenna having a slot formed therein; And
And a monopole antenna coupled to the patch antenna,
The patch antenna includes a branch for transmitting and receiving a signal of a predetermined band,
Wherein the patch antenna includes a first radiation part in which a slot is not formed and a second radiation part in which a slot is formed,
A branch for transmitting and receiving the signal of the predetermined band is formed in the second radiation portion,
The first and second radiating parts transmit and receive signals of a low band and the other part of the second radiating part transmits and receives signals of a predetermined band. The monopole antenna transmits and receives signals of a high band,
The second radiation portion and the monopole antenna are formed on the same plane at a predetermined distance,
Wherein the first radiating part further comprises a first line having a predetermined length and a predetermined width,
Wherein one end of the first line is connected to the feeding point via a predetermined connection line and the other end is connected to the first radiation unit. delete delete delete delete The method according to claim 1,
Wherein the first line includes a first edge of a surface on which the monopole antenna is formed, a first edge of a surface on which the second radiation portion is formed, and a surface on which the monopole antenna is formed, A built-in multiband antenna for a mobile communication terminal formed along a first edge of a facing surface. The method of claim 6,
Wherein the portion of the first radiating portion excluding the first line is formed on a surface facing the surface on which the second radiating portion is formed and a surface perpendicular to the surface on which the second radiating portion is formed. The method of claim 7,
Wherein the second radiating portion further comprises a first pattern whose shape is determined by the shape of the slot and whose one end is connected to a predetermined portion of the first line and a second line whose one end is connected to the other end of the first pattern Built - in multiband antenna for telecommunication terminals. The method of claim 8,
Wherein the branch is formed in a direction perpendicular to the first line along an edge of a surface on which the second radiation section is formed. The method of claim 9,
The monopole antenna is connected to a feed point through a predetermined connection line and is formed in a direction perpendicular to the first line along an edge opposite to an edge of a surface on which the branch is formed, .

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