WO2010067930A1

WO2010067930A1 - Small dual-band radiation element

Info

Publication number: WO2010067930A1
Application number: PCT/KR2009/002580
Authority: WO
Inventors: 이재두; 박종식; 김정호; 김상진
Original assignee: 주식회사 감마누
Priority date: 2008-12-08
Filing date: 2009-05-15
Publication date: 2010-06-17
Also published as: KR100911438B1

Abstract

The present invention relates to a dual-band radiation element which has a smaller size as compared to conventional dual-band antennas, and satisfies the characteristics of two frequency bands. The radiation element of the present invention comprises: a front high frequency antenna which is arranged on the front surface of a radiation substrate, and which radiates high frequency band signals fed through a feeding cable; a rear low frequency antenna which is arranged on the rear surface of the radiation substrate, and which radiates low frequency band signals fed through the coupling with the front high frequency antenna; a first low frequency parasitic element which is formed into an inverse L-shape, spaced apart from the radiation substrate, overlapped onto a portion of the upper surface of the radiation substrate, and disposed at both sides of the radiation substrate, and which controls resonance frequency with the rear low frequency antenna through the coupling with the rear low frequency antenna; and a second low frequency parasitic element spaced apart from the first low frequency parasitic element to expand the frequency bandwidth of the rear low frequency antenna; and a reflector arranged on the bottom surface of the radiation substrate to reflect signals radiated by the high frequency antenna and by the low frequency antenna.

Description

Small dual band radiation element

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small dual band radiation element, and more particularly, by placing a dipole antenna on the front and rear sides of a radiation substrate and by placing a parasitic element coupled to the rear dipole antenna on the side of the radiation substrate. The present invention relates to a dual band radiating element capable of satisfying characteristics of both desired frequency bands while miniaturizing its size compared to a dual band antenna.

With the rapid development of analog and digital communication technology in the world, various kinds of mobile communication services such as cellular, PCS, GSM and Iridium services using satellites are being implemented. PCS and the like are in commercial service, and recently, Digital Multimedia Broadcasting (DMB), which introduces the concept of personal multimedia, is also being serviced.

According to this trend, there is an increasing demand for a dual band antenna that can be used in not only one band but also two or more frequency bands for providing a service such as mobile communication.

In the case of the conventional dual band antenna, a high frequency antenna and a low frequency antenna are mainly designed, respectively, and then a band combiner is used to bundle two antennas into one. However, when the dual band antenna is implemented as a sector as described above, it is difficult to obtain satisfactory characteristics at both frequencies because the array spacing varies according to two frequencies.

In addition, in the conventional method, since a separate antenna for each band is required, a problem arises in that the size of the antenna becomes larger than necessary.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems described above, and an object of the present invention is to provide a dual-band radiating element capable of satisfying the characteristics of both desired frequency bands while miniaturizing the size of the conventional dual-band antenna. It is to provide.

Small dual-band radiating element of the present invention for achieving the above object is provided on the front surface of the radiation substrate, the front high frequency antenna for radiating the signal of the high frequency band fed through the feed cable; A rear low frequency antenna provided on a rear surface of the radiation substrate and configured to radiate a low frequency band signal fed through a coupling with the front high frequency antenna; It is formed in a '-' shape so as to overlap a portion of the upper surface of the radiation substrate spaced apart from the radiation substrate and disposed on both sides of the radiation substrate, the coupling of the rear low frequency antenna through the coupling with the rear low frequency antenna A first low frequency parasitic element adjusting a resonance frequency; A second low frequency parasitic element spaced apart from the first low frequency parasitic element by a predetermined distance and extending a frequency bandwidth of the rear low frequency antenna; And a reflector provided on a bottom surface of the radiation substrate and reflecting a signal radiated from the high frequency antenna and the low frequency antenna.

By having the configuration as described above, the present invention can transmit both high-frequency band and low-frequency band signals through one antenna, and has the advantage of satisfying both characteristics of both frequency bands.

In addition, the size of the conventional dual-band antenna can be significantly reduced, there is an advantage that can greatly reduce the restrictions on installation and operation.

1 is a perspective view showing the overall configuration of a small dual-band radiation device according to the present invention.

FIG. 2 is a perspective view in which the radiation substrate is not illustrated in order to indicate an arrangement state of a front high frequency antenna and a rear low frequency antenna in the small dual band radiation element of FIG. 1.

3 is a view showing a specific configuration of the front high frequency antenna 100 of the small dual band radiation element according to the embodiment of the present invention.

4 is a view showing a specific configuration of the rear low-frequency antenna 200 of the small dual-band radiating element according to an embodiment of the present invention.

5 is a diagram illustrating a current distribution of a front high frequency antenna of a small dual band radiating element according to an exemplary embodiment of the present invention.

6 is a diagram illustrating a current distribution of a rear low frequency antenna of a small dual band radiating element according to an exemplary embodiment of the present invention.

7 is a graph showing the S11 value of the dual-band radiating element according to an embodiment of the present invention.

100: front high frequency antenna 200: rear low frequency antenna

300: first low frequency parasitic element 400: second low frequency parasitic element

500: reflector

110:

feeder

120a, 120b: parallel feed line portion

130, 140:

front dipole antenna

150a, 150b: front parasitic element

111: core wire hole 112: ground via hole

113: balun hole 114: printed circuit pattern

210:

first coupling part

220a, 220b: rear dipole antenna

230a, 230b: second coupling part 240, 250: antenna extension part

260a, 260b: rear parasitic element 115: first circular circuit pattern

116: second circular circuit pattern

The small dual band radiation device of the present invention includes a front high frequency antenna provided on a front surface of a radiation substrate and radiating a signal of a high frequency band fed through a feed cable; A rear low frequency antenna provided on a rear surface of the radiation substrate and configured to radiate a low frequency band signal fed through a coupling with the front high frequency antenna; It is formed in a '-' shape so as to overlap a portion of the upper surface of the radiation substrate spaced apart from the radiation substrate and disposed on both sides of the radiation substrate, the coupling of the rear low frequency antenna through the coupling with the rear low frequency antenna A first low frequency parasitic element adjusting a resonance frequency; A second low frequency parasitic element spaced apart from the first low frequency parasitic element by a predetermined distance and extending a frequency bandwidth of the rear low frequency antenna; And a reflector provided on a bottom surface of the radiation substrate and reflecting a signal radiated from the high frequency antenna and the low frequency antenna.

In this case, the front high frequency antenna, a power supply unit for receiving a signal of a high frequency band from the power supply cable; A parallel feed line unit for transmitting a signal of a high frequency band fed to the feed unit to a front dipole antenna; A front dipole antenna which radiates the high frequency band signal transmitted from the parallel feed line unit to free space; It is preferably configured to include.

The power feeding unit may include: a core wire hole through which a core wire (+) of the feed cable is connected through the radiation board from a rear surface of the radiation board; A ground via hole connected through the radiation substrate and electrically connected to a ground line (−) of the feed cable; And a balun hole in which a balun cable, which is paired with the feed cable and serves as a balun, is inserted and connected. The core wire hole and the balun hole may be electrically connected through a printed circuit pattern.

The front radio frequency antenna may further include a front parasitic element arranged in parallel with the front dipole antenna on a front surface of the radiation substrate to extend a frequency bandwidth of the front dipole antenna.

The rear low frequency antenna may include a coupling unit configured to receive a low frequency band signal through a coupling with the front high frequency antenna; A rear dipole antenna having one side connected to the coupling part and radiating a low frequency band signal fed from the coupling part to free space; An antenna extension unit arranged perpendicular to the longitudinal direction of the rear dipole antenna and having one side connected to the other side of the rear dipole antenna; And a second coupling part positioned at a portion where the rear dipole antenna and the antenna extension part are connected and coupled to the first low frequency parasitic element.

In this case, the rear low frequency antenna, the rear side of the radiation substrate is arranged in parallel with the antenna extension, it is preferable to further include a rear parasitic element for extending the frequency bandwidth of the rear dipole antenna.

In addition, the first low frequency parasitic elements are preferably arranged such that the plane parallel to the radiation substrate is located at two center portions of the four corners of the radiation substrate on which the front dipole antenna is not formed.

The method of claim 1 or 7, wherein the second low frequency parasitic elements are spaced apart from the first low frequency parasitic elements by a predetermined distance and are disposed on the rear surface of the first low frequency parasitic elements based on the radiation substrate. desirable.

Details of the above object and technical configuration of the present invention and the effects thereof according to the present invention will be more clearly understood by the following detailed description based on the accompanying drawings.

Prior to the description of the present invention, a detailed description of known functions or configurations related to the present invention will be omitted if it is determined that the gist of the present invention may be unnecessarily obscured.

In addition, terms to be described below are terms defined in consideration of functions in the present invention, which may vary according to intention or custom of users and operators. Therefore, such a definition should be determined based on the contents described throughout the specification.

1 is a perspective view showing the overall configuration of a small dual-band radiating element according to the present invention, Figure 2 is a radiation substrate for indicating the arrangement of the front high frequency antenna and the rear low frequency antenna in the small dual band radiating element shown in FIG. A perspective view is omitted.

As shown, the small dual-band radiating element includes a front high frequency antenna 100, a rear low frequency antenna 200, a first low frequency parasitic element 300, a second low frequency parasitic element 400, and a reflecting plate 500. It is configured by.

The front high frequency antenna 100 is provided on the front surface of the radiation substrate, and radiates a signal of a high frequency band fed through a feed cable.

The feed cable receives feed signals of (+) current and (−) current from the outside to feed the front high frequency antenna 100 and the rear low frequency antenna 200. In this case, the front high frequency antenna 100 is directly connected to a feed cable to receive a signal, and the rear low frequency antenna 200 receives a feed signal through a coupling in a portion overlapping with the front high frequency antenna 100. The feed cable may be implemented as, for example, a coaxial cable for power transmission or signal transmission, and includes an inner conductor (core wire) serving as a signal line and an outer conductor serving as a grounding wire.

The rear low frequency antenna 200 is provided on the rear surface of the radiation substrate and radiates a low frequency band signal fed through the coupling with the front high frequency antenna.

The rear low frequency antenna 200 rotates the front high frequency antenna 100 by 90 degrees.

The first low frequency

parasitic elements

300a and 300b are formed in a '-' shape so as to overlap a portion of an upper surface of the radiation substrate by being spaced apart from the radiation substrate at a predetermined interval and disposed on both sides of the radiation substrate, and the rear low frequency Coupling with the antenna adjusts the resonance frequency of the rear low frequency antenna.

Specifically, the first low frequency parasitic elements (300a, 300b), of the four corners of the rectangular radiation substrate, of the 'A' shape at the center of the two corners, the front high frequency antenna 100 is not formed The upper surface (ie, the surface parallel to the radiation substrate) is disposed so as to be located respectively. As can be seen in FIG. 2, when the first low frequency

parasitic elements

300a and 300b are disposed as described above, the first low frequency

parasitic elements

300a and 300b are disposed on the rear surface of the radiation substrate. ) And the radiation substrate are spaced apart from each other by a predetermined distance therebetween, and coupling occurs with the rear low frequency antenna 200 at the overlapping portion, so that the rear low frequency antenna 200 can copy a signal in a low frequency band. Make sure

The second low frequency

parasitic elements

400a and 400b are disposed on the rear surface of the first low frequency

parasitic elements

300a and 300b when the second low frequency

parasitic elements

300a and 300b are spaced apart from the first low frequency

parasitic elements

300a and 300b by reference to the radiation substrate. It serves to extend the frequency bandwidth of the rear low frequency antenna.

The reflector 500 is provided on the bottom surface of the radiation substrate and reflects the signal radiated from the high frequency antenna and the low frequency antenna.

As shown, the front high frequency antenna 100 includes a feed unit 110, parallel

feed line units

120a and 120b,

front dipole antennas

130 and 140, and front

parasitic elements

150a and 150b. It is composed.

The power feeding unit 110 receives a signal of a high frequency band from the power feeding cable.

Herein, the configuration of the power supply unit 110 will be described in detail. The power supply unit 110 includes a core wire hole 111 through which a core wire (+) of the feed cable is connected through the radiation board from the rear surface of the radiation board, and the A ground via hole 112 connected through the radiation substrate and electrically connected to a ground line (-) of the feed cable, and a balun hole 113 into which a balun cable serving as a balun is inserted into and connected to the feed cable; The core wire hole and the balloon hole are configured to be electrically connected to each other through the printed circuit pattern 114. According to such a configuration, a positive current is applied to the core wire hole 111 from the feed cable and a negative current is applied to the ground via hole 112.

Here, the role of balun (balance / unbalance) is to make resonance by matching a difference between a positive feed signal and a negative feed signal of a feed cable, which is a known technique in the antenna field.

The parallel

feed line units

120a and 120b transmit a high frequency band signal fed to the feed unit 110 to the front dipole antenna.

The parallel feed line portions 120a and 12b are configured such that two feed lines for transferring positive and negative currents from the feed portion 110 to the

front dipole antennas

130 and 140 are arranged in parallel. do.

In this case, the parallel

feed line units

120a and 120b match the impedance between the feed unit 110 and the

front dipole antennas

130 and 140. That is, although the impedance of the power supply unit 110 and the impedance between the

front dipole antennas

130 and 140 are different, the feed signal passes through the parallel

feed line units

120a and 120b in the power supply unit 110 (the front dipole antenna ( 130 and 140, the parallel

feed line units

120a and 120b convert the impedance of the feed unit 110 into the impedances of the

front dipole antennas

130 and 140.

The

front dipole antennas

130 and 140 copy the signal of the high frequency band transmitted from the parallel feed line unit to free space.

The

front dipole antennas

130 and 140 may include a front first dipole antenna 130 and a front second dipole antenna 140 configured up and down symmetrically with respect to the power feeding unit 110. Here, the front first dipole antenna 130 is located at a quarter wavelength away from the power supply unit 110 in the upward direction, and the front second dipole antenna 140 is 1 / downward in the downward direction from the power supply unit 110. 4 wavelengths away.

In addition, the antenna component 130a receiving positive (+) current from the front first dipole antenna 130 and the antenna component 130b receiving negative (−) current are bilaterally symmetric, and the front second dipole antenna ( At 140, the antenna component 140a to which the positive current is applied and the antenna component 140b to which the negative current is applied are symmetrical.

Meanwhile, the front high frequency antenna 100 further includes front

parasitic elements

150a and 150b arranged in parallel with the front first dipole antenna 130 and the front second dipole antenna 140 on the front surface of the radiation substrate. can do. The front

parasitic elements

150a and 150b have currents having the same direction as that of the front first dipole antenna 130 and the front second dipole antenna 140, and thus, the front first dipole antenna 140 and It serves to extend the frequency bandwidth of the front second dipole antenna 140.

As shown, the rear low frequency antenna 200 includes a first coupling part 210,

rear dipole antennas

220a and 220b,

second coupling parts

230a and 230b,

antenna extension parts

240 and 250, It is configured to include the rear

parasitic elements

260a and 260b, and the front high frequency antenna 100 is rotated 90 degrees.

The first coupling unit 210 feeds the low frequency band signal to the rear low frequency antenna 200 through the coupling with the front high frequency antenna 100. As described above, the power feeding to the rear low frequency antenna 200 is performed through the coupling with the front high frequency antenna 100, rather than the direct power feeding method by the cable. In detail, the power feeding unit 110 of the front high frequency antenna 100 positioned on the front surface corresponding to the first coupling unit 210 is coupled to each other based on the radiation substrate, thereby feeding power to the rear low frequency antenna 200. .

One side of the

rear dipole antennas

220a and 220b is connected to the first coupling unit 210 to copy the low frequency band signal fed from the coupling unit to free space. In the case of the front high frequency antenna 100, a portion corresponding to the

rear dipole antennas

220a and 220b forms a parallel

feed line portion

120a and 120b, but the rear low frequency antenna 200 is not a feed line. The difference is that it functions as a dipole antenna.

The

second coupling units

230a and 230b are portions in which coupling occurs between the first low frequency

parasitic elements

300a and 300b and the rear low frequency antenna 200. As shown in FIGS. 1 and 2, the first low frequency

parasitic elements

300a and 300b have front portions corresponding to the

second coupling portions

230a and 230b on the rear surface of the radiation substrate. It is placed at a certain distance apart. Accordingly, coupling occurs with the first low frequency

parasitic elements

300a and 300b in a region of the

second coupling units

230a and 230b of the rear low frequency antenna 200, thereby causing low frequency through the

rear dipole antennas

220a and 220b. The signal in the band is copied.

The

antenna extensions

240 and 250 correspond to the

front dipole antennas

130 and 140 of the front high frequency antenna 100, and are arranged perpendicular to the longitudinal direction of the

rear dipole antennas

220a and 220b as shown. The

second coupling parts

230a and 230b may be connected to the other side of the

rear dipole antennas

220a and 220b.

By providing the

antenna extension parts

240 and 250 in this manner, the lengths of the

rear dipole antennas

220a and 220b can be reduced, thereby minimizing the overall size of the small dual band radiating element according to the present invention.

Meanwhile, in the rear low frequency antenna 200 of FIG. 4, the first circular circuit pattern 115 surrounding the balloon hole 113 in a circle is spaced apart from the rear dipole antenna 220a by a predetermined distance. In addition, the second circular circuit pattern 116 including one or more ground via holes 112 and being surrounded by a circle at a predetermined interval with respect to the core wire 111 may also be spaced apart from the rear dipole antenna 220b at a predetermined interval. It is.

Meanwhile, the rear low frequency antenna 200 is arranged in parallel with the

antenna extension parts

240 and 250 on the rear side of the radiation substrate like the front high frequency antenna 100 to extend the frequency bandwidth of the

rear dipole antennas

220a and 220b. The

parasitic elements

260a and 260b may be further included.

As shown, the front high frequency antenna 100 is fed through a cable in the feed section 110 of the antenna center portion, the fed signal is the front dipole antenna 130 through the parallel feed line (120a, 120b) , 140) and copied into free space. At this time, a current flows in the front portion of the high frequency antenna 100 as shown, but no coupling occurs in the rear surface, and thus no current flows.

As shown in the drawing, the rear low frequency antenna feeds a low frequency signal by coupling occurring in the first coupling part 210 overlapping the front high frequency antenna, and the first low frequency parasitic element (2) in the

second coupling parts

230a and 230b. It is coupled to the 300a, 300b to operate as a low-frequency antenna, the low-frequency signal is radiated to the free space through the rear dipole antenna (220a, 220b).

As shown, when the dual band radiation device according to the present invention is implemented, it can be seen that the resonance in the low frequency 800MHz band and the high frequency 2000MHz band, respectively.

Although specific embodiments of the present invention have been described in detail above, those skilled in the art to which the present invention pertains may implement the present invention in other specific forms without changing the technical spirit or essential features thereof. It should be understood that the embodiments described above are exemplary in all respects and that the present invention is not limited to those described in the detailed description. The scope of the present invention is indicated by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents are included within the scope of the present invention. Should be interpreted.

Claims

A front high frequency antenna provided on a front surface of the radiation substrate and configured to copy a signal of a high frequency band fed through a power supply cable;

A rear low frequency antenna provided on a rear surface of the radiation substrate and configured to radiate a low frequency band signal fed through a coupling with the front high frequency antenna;

It is formed in a '-' shape so as to overlap a portion of the upper surface of the radiation substrate spaced apart from the radiation substrate and disposed on both sides of the radiation substrate, the coupling of the rear low-frequency antenna through the coupling with the rear low-frequency antenna A first low frequency parasitic element adjusting a resonance frequency;

A second low frequency parasitic element spaced apart from the first low frequency parasitic element by a predetermined distance and extending a frequency bandwidth of the rear low frequency antenna;

A reflection plate provided on a bottom surface of the radiation substrate and reflecting a signal radiated from the high frequency antenna and the low frequency antenna;

Small dual band radiation device configured to include.
The method of claim 1,

The front high frequency antenna,

A feeding unit configured to receive a signal of a high frequency band from the feeding cable;

A parallel feed line unit for transmitting a signal of a high frequency band fed to the feed unit to a front dipole antenna;

A front dipole antenna which radiates the high frequency band signal transmitted from the parallel feed line unit to free space;

Small dual band radiation device configured to include.
The method of claim 2,

The feed section,

A core wire hole through which a core wire (+) of the feed cable is connected through the radiation board from a rear surface of the radiation board;

A ground via hole connected through the radiation substrate and electrically connected to a ground line (−) of the feed cable;

And a balun hole in which a balun cable, which is paired with the feed cable and serves as a balun, is inserted and connected thereto.

And the core wire hole and the balloon hole are electrically connected through a printed circuit pattern.
The method according to claim 2 or 3,

The front high frequency antenna,

And a front parasitic element arranged in parallel with the front dipole antenna on a front surface of the radiation substrate to extend a frequency bandwidth of the front dipole antenna.
The method of claim 1,

The rear low frequency antenna,

A coupling unit configured to receive a low frequency band signal through the coupling with the front high frequency antenna;

A rear dipole antenna having one side connected to the coupling part and radiating a low frequency band signal fed from the coupling part to free space;

An antenna extension unit arranged perpendicular to the longitudinal direction of the rear dipole antenna and having one side connected to the other side of the rear dipole antenna;

A second coupling part positioned at a portion where the rear dipole antenna and the antenna extension part are connected and coupled to the first low frequency parasitic element;

Small dual band radiation device configured to include.
The method of claim 5,

The rear low frequency antenna,

And a rear parasitic element arranged on a rear surface of the radiation substrate in parallel with the antenna extension to extend a frequency bandwidth of the rear dipole antenna.
The method of claim 2,

The first low frequency parasitic elements may be arranged in such a manner that the plane parallel to the radiation substrate is disposed at the centers of two corners of the four edges of the radiation substrate on which the front dipole antenna is not formed. Radiation elements.
The method according to claim 1 or 7,

And the second low frequency parasitic element is disposed on a rear surface of the first low frequency parasitic element when the second low frequency parasitic element is spaced apart from the first low frequency parasitic element based on the radiation substrate.