DE102011056464A1 - Broadband-frame antenna for e.g. direction finding in band ranging from middle frequency band to very high frequency band, has feed circuit part connected with feed part to supply signal to frame element or to receive signal from outside - Google Patents

Abstract

The antenna has a frame element (200) including a plate-like main-frame surface (210) formed in a frame periphery. Sub-frame surfaces (230) are folded relative to main-frame surface during formation of a preset inclination angle. A frame feed part (240) includes a frame fastening end (241) arranged at both ends of the main-frame surface. A printed circuit board-connecting end (242) is connected with the fastening end for coupling with a feed circuit part (220). The circuit part is connected with the feed part for supplying a signal to the frame element or for receiving the signal from outside.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the priority of Korean Patent Application No. 10-2010-0128352 , filed on Dec. 15, 2010, which is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

Field of the invention

Embodiments of the present invention relate to a loop antenna, and more particularly to a loop antenna that has a reduced volume, is highly portable and easy to accommodate, as compared to conventional antennas according to the related art.

Description of the associated technique

In general, a loop antenna has been used for electric field strength measurement and direction finding in bands ranging from a medium frequency (MF) band to a ultra short wave (VHF) band. In the AM / FM band, the loop antenna has been widely used for radio reception, and in a UHF band, the loop antenna has been used as a TV indoor antenna. And the size of an opening, such as. For example, the length, diameter, and the like of the antenna is determined by the wavelength of the operating frequency to match the corresponding band, which is why the loop antenna has been used mainly in a low-frequency band. When selecting other types of antennas with the loop antenna, the lower the frequency becomes, the longer the corresponding wavelength becomes, and as a result, the size of the other types becomes larger. Due to the size of the other types, it is difficult to choose a place to set up the other types or to set the other types to be movable. On the other hand, since an electrically small loop antenna may have a slightly degraded antenna efficiency but can also receive a signal in a much smaller size than a wavelength corresponding to one wavelength of an operating frequency band signal, the small-size loop antenna may be used for a receiver system Size reduced weight and reduced costs and can be applied due to easy transportability and ease of installation on a portable device.

However, because of its small size, the small-sized loop antenna has a low antenna efficiency and low gain, and has a high quality value because of low antenna resistance and a very large reactance antenna component, so that it is difficult to realize wide-band matching.

In addition, the frame member of the loop antenna can be mainly made by bending a wire, a tubular conductor or a plate-shaped conductor in a circular, triangular or square shape. As a method for connecting the frame member to a feed part, a soldering method has been mainly used.

For example, a general plate-shaped loop antenna is shown in FIG 1 shown. As in 1 2, the general plate-shaped loop antenna according to the prior art has a structure in which a frame member 100 by folding or bending the plate-shaped frame surface 110 is formed into a circular, square or polygonal shape and a frame feed part 140 and a power circuit part 120 at one end of the frame element 100 be joined together by soldering.

However, when soldering is performed, the shape and arrangement of the frame feeder are 140 possibly limited, its construction may be complicated, and the soldering region between the frame supply part 140 and the power circuit part 120 is possibly prone to shock.

Brief description of the invention

An embodiment of the present invention is directed to providing a loop antenna capable of improving the antenna efficiency without greatly changing the radiation resistance of the antenna by increasing the frame width.

And another embodiment of the present invention is directed to providing the structure fixedly connected between the frame member and the feed circuit by means of a bolting method.

The objects of the present invention are not limited to the above-mentioned objects, and therefore, other objects and advantages of the present invention, which are not mentioned, can be recognized by the following description and will be more clearly understood by embodiments of the present invention. It is also easy to see that the tasks and benefits of the present invention can be realized by the means described in the claims and combinations thereof.

According to an embodiment of the present invention, a loop antenna includes: a frame member including a plate-shaped main frame surface and a sub-frame surface, wherein the plate-shaped main frame surface is formed in a frame periphery of the frame antenna and the sub-frame surface at left and right surfaces of the frame antenna plate-shaped main frame surface is arranged and folded during formation of a predetermined inclination angle relative to the plate-shaped main frame surface; a frame feed member including frame attachment ends and a circuit board connection end, wherein the frame attachment ends are disposed at both ends of the main frame surface, and the circuit board connection end is connected to the frame attachment end to be coupled to a feed circuit member; and a supply circuit part connected to the frame supply part to supply a signal to the frame element or to receive a signal from the outside.

According to another embodiment of the present invention, a loop antenna includes: a frame member including a plate-shaped main frame surface and a sub-frame surface, wherein the plate-shaped main frame surface is formed along a frame periphery of the frame antenna and the sub-frame surface is formed on left and right surfaces the plate-shaped main frame surface is arranged and folded during formation of a predetermined inclination angle relative to the main frame surface; a first frame feed member including a first frame attachment end and a first circuit board connection end, wherein the first frame attachment end is disposed at both ends of a first side of the main frame surface and the first circuit board connection end is connected to the first frame attachment end coupled to a feed circuit member to become; a supply circuit part connected to the first frame supply part for supplying a signal to the frame element or receiving a signal from the outside; a second frame feed member including second frame attachment end and a second circuit board connection end, wherein the second frame attachment ends are disposed at both ends of a second side of the main frame surface and the second circuit board connection end is connected to the second frame attachment end to be connected to an element insertion member become; and wherein the element insertion part is connected to the second frame feed part and embodied as a printed circuit board or a module for inserting a concentrated element.

Brief description of the drawings

1 is a perspective view of a general plate-shaped loop antenna.

2 Fig. 12 is a perspective view of a small loop antenna which is easily assembled and disassembled according to an embodiment of the present invention.

3 Fig. 10 is an exploded perspective view showing the state of attachment of a feeding member by means of a screw and a nut in the loop antenna according to the embodiment of the present invention.

4 Fig. 10 is an exploded perspective view showing the attachment state of a feeding member by means of a screw and a power circuit holder in the loop antenna according to the embodiment of the present invention.

5 Fig. 10 is a perspective view of a loop antenna according to another embodiment of the present invention.

6 FIG. 10 is an exploded perspective view showing the attachment state of a feed member in accordance with a rearranged feed circuit part in the loop antenna according to the embodiment of the present invention. FIG.

7 FIG. 12 is a graph showing a comparison result of the simulated gain of the loop antenna according to the embodiment of the present invention and that of a general loop antenna according to the related art.

8th FIG. 12 is a graph showing a comparison result of the simulated return loss of the loop antenna according to the embodiment of the present invention and that of a general loop antenna according to the related art.

DESCRIPTION OF SPECIAL EMBODIMENTS

Embodiments of the present invention will be described below in more detail with reference to the accompanying drawings. However, the present invention may be embodied in various forms and is not to be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will become the scope of the present invention Completely convey the invention. Throughout the disclosure, like reference numbers refer to like parts throughout the several figures and embodiments of the present invention.

Throughout the description, the case that any part is "connected" to the other part, both the case that the parts are electrically connected to each other via other interposed elements, as well as the case that the parts are directly connected to each other , Unless explicitly stated to the contrary, the term "include" and variations such "Includes" or "comprising" so as to imply the inclusion of specified elements, but not the exclusion of any other elements.

A loop antenna according to an embodiment of the present invention may have a plate-shaped frame surface, and may have the effects of improved antenna efficiency and reduced loss resistance without greatly changing the radiation resistance of the antenna by increasing the width of the frame surface. In addition, the frame antenna has a broadband characteristic due to the increase in the frame width as compared with the narrow-frame width antenna. In addition, the loop antenna folds a portion of the frame surface by a predetermined angle, thereby reducing the increase in volume due to the expansion of the frame width. Further, the loop antenna includes a connection part which facilitates mounting and dismounting of a power circuit board or a board-mounted device board, which can be inserted to improve impedance matching or antenna directivity, in a frame member.

2 Figure 11 is a perspective view of a small rigid loop antenna that is easily assembled and disassembled, according to an embodiment of the present invention.

As in 2 As shown, the loop antenna according to the embodiment of the present invention includes a frame member 200 , and the frame element 200 contains a plate-shaped main frame surface 210 and sub-frame surfaces 230 , In this case, the plate-shaped main frame surface 210 formed along the frame periphery of the loop antenna. And the sub-frame surfaces 230 are left and right of the plate-shaped main frame surface 210 formed and during formation of a predetermined inclination angle relative to the main frame surface 210 folded. In addition, the loop antenna includes a feed circuit part 220 , wherein the supply circuit part 220 with a frame feed 240 connected is. And the power circuit part 220 serves to the frame element 200 to supply a signal or to receive a signal from the outside. Furthermore, the loop antenna contains a frame feed part 240 , and a frame feed 240 contains a frame attachment end 241 and a circuit board connection end 242 , Here is the frame attachment end 241 at both ends of the main frame surface 210 arranged. And the PCB connection end 242 is with the frame attachment end 241 connected and is connected to the power circuit part 220 coupled. In the loop antenna with the frame element 200 is the supply circuit part 220 by a screw fastening method in contrast to the soldering method according to the associated technique with the frame feed part 240 coupled.

The main frame area 210 is herein formed along an octagonal circumference, but the shape of the frame surrounding is not limited thereto and can be variously changed in accordance with the application.

It also has the sub-frame area 230 a shape in which the left and right surfaces of the main frame surface 210 folded at a predetermined angle toward the center of the frame, so that they are aligned with the main frame surface 210 are symmetrical. When the predetermined angle is 0 °, the sub-frame surface exists 230 on the same two-dimensional plane as the main frame surface 210 (the same loop antenna as 1 ), so that the antenna height in the Z-axis direction has the same value as the frame width A of a general loop antenna as shown in FIG 1 recognizes. However, when the angle is gradually increased to 90 ° or less, the overall frame width (main frame width + subframe width) coincides with A, but by folding the frame surface on both sides, so that the antenna height in the direction of the Z axis B, as in 2 shown, you get a reduced volume.

At the end of the frame element 200 the loop antenna according to the embodiment of the present invention is the frame feed part 240 , the frame attachment end 241 and the PCB connection end 242 contains, with the supply circuit part 220 connected. The state of attachment of the frame feeder 240 in the loop antenna is with reference to 3 and 4 described in detail.

3 FIG. 10 is an exploded perspective view showing a state of attachment of the feeding member by means of a screw and a nut in the loop antenna according to the embodiment of the present invention; and FIG 4 is an exploded perspective view showing a state of attachment of the feed by means of a screw and a feeder circuit holder in the loop antenna according to the embodiment of the present invention.

In the embodiment of the present invention, as in 3 is shown, the frame mounting end 241 inserted in a square channel groove in the PCB connection end 242 is buried, and a screw 260 gets into a screw insertion hole 244 resting on a surface of the PCB connection end 242 is formed, and a in the supply circuit part 220 trained screw through hole is inserted and then by means of a nut 261 at the back of the power circuit part 220 attached, causing the frame element 200 fixed to the power circuit part 220 is connected. In another embodiment of the present invention, as in 4 shown is a power circuit mount 270 on the back of the supply circuit part 220 arranged, and one side thereof is threaded to a screw 260 to be connected, whereby the frame element 200 fixed to the power circuit part 220 is connected.

The susceptibility of the existing soldering process is the resulting from an external shock interruption in the soldered portion between the power circuit part 220 and the frame feed 240 , If the screw fastening method is used, the problem can be solved. In this case, the frame attachment end 241 and the PCB connection end 242 soldered together by solder through a solder hole 234 is penetrated therein, so that the frame attachment end 241 and the PCB connection end 242 can be connected together more firmly.

In addition, the position of the screw insertion hole is 244 in the PCB connection end 242 not on the in 3 and 4 shown example and can therefore in accordance with the arrangement of the power circuit part 220 be changed freely.

Furthermore, the shape of the rectangular groove is at the board connection end 242 , which is arranged to the frame attachment end 241 with the PCB connection end 242 to couple, not limited and therefore in accordance with the shape of the frame attachment end 241 be changed variously.

In addition, the frame mounting end 241 and the PCB connection end 242 Although shown in a separate form, as in 2 to 4 but they can be changed to have an integrated shape.

5 Fig. 12 is a perspective view of the loop antenna according to another embodiment of the present invention.

As in 5 In addition, according to another embodiment of the present invention, the loop antenna further includes an element insertion part 320 in addition to a frame element 300 and a power circuit part 310 ,

The frame element 300 is the same as the frame element 200 from 2 and includes a plate-shaped main frame surface and a sub-frame surface. In this case, the plate-shaped main frame surface is formed along a frame circumference. And the sub-frame surface is disposed on the left and right surfaces of the plate-shaped main frame surface and folded while forming a predetermined inclination angle relative to the main frame surface. But the frame element is different 300 from that of 2 in that the frame element 300 consists of two elements.

The power circuit part 310 is with a first frame feed 340 connected, which the first frame mounting end 341 and the first circuit board connection end 342 contains, and the element insertion part 320 , which is a printed circuit board or a module for inserting a lumped element to improve the impedance matching or the directional characteristic of an antenna, is provided with a second frame feed part 350 coupled, which a second frame attachment end 351 and a second circuit board connection end 352 contains. The connection method between the element insertion part 320 and the second frame feeder 350 uses the same screw connection method as 2 and therefore a detailed description thereof will be omitted.

In addition, the connection method between the frame attachment end 341 or 351 and the PCB connection end 342 or 352 or the position of the screw insertion hole is the same type as that in FIG 2 to 4 described mounting method of the frame attachment end 241 and the PCB connection end 242 and therefore a detailed description thereof will be omitted.

6 Fig. 10 is an exploded perspective view showing a state of attachment of the feeding member in accordance with rearrangement of a feeding circuit part in the loop antenna according to the embodiment of the present invention. 6 shows the attachment state of a feed part in the loop antenna with a Power circuit part that is different than the one in 3 and 4 is arranged shown.

As in 6 shown has a frame food portion 240 a separate mold, which consists of the frame mounting end and the PCB connection end in 3 and 4 exists while a frame feed part 440 in 6 has an integrated shape. In this structure, the position of the power circuit part is 420 changed. And an area of the frame food piece 440 is with a screw insertion hole 444 Mistake. For a connection between the supply circuit part 420 and the frame feed 440 will be a screw 460 in the screw insertion hole 444 and a screw through hole of the power circuit part 420 inserted and is attached to a power circuit mount 470 attached.

7 FIG. 12 is a graph showing a comparison result of the simulated forward gain (φ = 0 °, θ = 90 °) of the loop antenna according to the embodiment of the present invention, wherein the opposite side of the in 5 and the general loop antenna according to the related art, wherein the frame surface is not folded.

In 7 Comparing the loop antenna according to the embodiment of the present invention with two kinds of general loop antennas 1 and 2, a resistance of 300 Ω is uniform in the element insertion part 320 inserted, which on the opposite side of the supply circuit part 310 is arranged to realize a unidirectional structure, and the frame circumferences of all types of loop antennas are about 1100 mm, and the frame widths of the two general loop antennas are 60 mm and 90 mm, respectively. in the case of the antenna according to the embodiment of the present invention, the results for the case where the overall frame width is set uniformly at 90 mm but the main frame surface is 60 mm and each of the widths of the sub-frame surface are left and right sides folded by 45 ° relative to the main frame surface, 15 mm is compared. In this case, the frame heights of the general frame antennas in the Z direction are 60 and 90 mm, respectively, and the frame height of the loop antenna according to the embodiment of the present invention in the Z direction is approximately 81.2 mm.

In this case one recognizes from the results of 7 in that the loop antenna according to the embodiment of the present invention has better results than the general loop antenna 1 having the frame width of 60 mm and worse results than the general loop antenna 2 having the frame width of 90 mm.

8th FIG. 12 is a graph showing the comparison results of the simulated return loss of the loop antenna according to the embodiment of the present invention and that (or the simulated return loss) of the general loop antennas 1 and 2.

In 8th The loop antenna according to the embodiment of the present invention shows results approximately similar to the return loss of the general loop antenna 2 and shows results improved as compared with those of the general loop antenna 1.

Comparing bands in which the return loss of three kinds of loop antennas is 15 dB or less, herein the general loop antenna is 1 0 MHz to 175 MHz, the general loop antenna 2 is 0 MHz to 254 MHz, and the loop antenna according to the embodiment of the present invention Invention is 0 MHz to 273 MHz. It can be seen that the bandwidth is considerably broadened due to the modification of the frame width and the shape.

As stated above, the embodiments of the present invention can provide a broad band loop antenna in which the volume of the loop antenna does not increase in the system requiring the small loop antenna, although the efficiency and gain of the antenna are improved by the width of the plate-shaped frame member is increased.

In addition, the embodiments of the present invention can variously change the gain or 3 dB beam width on the radiation pattern according to the application by changing the angle and the width of the sub-frame surface relative to the main frame surface.

Furthermore, in the embodiments of the present invention, the end of the frame member (frame attachment end) may be inserted into the predetermined groove buried in the board connection end, and the bolt may be inserted into the bolt hole formed on a surface of the board connection end, and the through hole or the element insertion part formed in the feeding circuit part is inserted to solve the thin-structure lifting phenomenon attributed to the excessive soldering temperature at the time of manufacturing and the susceptibility of the soldering section to vibration and shock in a mobile environment, and thereby the frame member and the feeding circuit part or connect the printed circuit board (element insertion part) more firmly to insert the element.

Furthermore, the embodiments of the present invention can facilitate performance testing in accordance with parameter changes by facilitating the replacement of the feed circuit or the insertion elements due to the screw fastening process between the frame member and the feed circuit member or the member insertion member and thereby be easily checked during the antenna development process.

Further, the embodiments of the present invention can freely arrange and couple the feeding circuit part or the element insertion part in accordance with the position in which the screw hole is formed in the board connection end on the frame surface in the vertical or horizontal direction without bending or locking the frame fixing end deform.

While the present invention has been described in terms of particular embodiments thereof, those skilled in the art will recognize that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• KR 10-2010-0128352 [0001]

Claims (15)

A loop antenna comprising: a frame member including a plate-shaped main frame surface and a sub-frame surface, wherein the plate-shaped main frame surface is formed in a frame periphery of the loop antenna and the sub-frame surface is disposed on left and right surfaces of the plate-shaped main frame surface, and folded while forming a predetermined inclination angle relative to the plate-shaped main frame surface; a frame feeder containing frame attachment ends and a circuit board connection end, wherein the frame attachment ends are disposed at both ends of the main frame surface, and the circuit board connection end is connected to the frame attachment end to be coupled to a supply circuit part; and a supply circuit part connected to the frame supply part to supply a signal to the frame element or to receive a signal from the outside. The loop antenna of claim 1, wherein a folded shape of the sub-frame surface is a left-right symmetry around the main frame surface and the folded surface faces a center of the frame. A loop antenna according to claim 2, wherein said predetermined inclination angle is less than 90 °. The loop antenna of claim 1, wherein the frame mounting end and the circuit board connection end are assembled in an integrated form or a separate form. The loop antenna according to claim 4, wherein when the frame mounting end and the board connecting end are in the separated form, the frame mounting end is inserted in a predetermined groove formed in the board connecting end. The loop antenna according to any one of claims 1 to 5, wherein the board connection end has a screw insertion hole formed in a face thereof for coupling with the feeding circuit part. The loop antenna according to claim 6, wherein the feed circuit part has a screw insertion hole formed in a face thereof for coupling with the board connection end. The loop antenna according to claim 7, wherein the feeding circuit part is inserted by a screw fastening method in which a screw is screwed into the screw insertion hole formed in a face of the board connection end and the screw through hole formed in the feeding circuit part, and then the screw is tightened from a back side of the feeding circuit part by means of a nut or the screw is attached to a thread formed in an additional feeder circuit mount, is coupled to the frame feed part. A loop antenna comprising: a frame member including a plate-shaped main frame surface and a sub-frame surface, wherein the plate-shaped main frame surface is formed along a frame periphery of the loop antenna and the sub-frame surface is disposed on left and right surfaces of the plate-shaped main frame surface and folded while forming a predetermined inclination angle relative to the main frame surface; a first frame feed part including a first frame attachment end and a first circuit connection end, wherein the first frame attachment end is disposed at both ends of a first side of the main frame surface, and the first circuit board connection end is connected to the first frame mounting end to be coupled to a power supply circuit part; a supply circuit part connected to the first frame supply part for supplying a signal to the frame element or receiving a signal from the outside; a second frame feed part including a second frame attachment end and a second circuit board connection end, wherein the second frame attachment ends are disposed at both ends of a second side of the main frame surface, and the second circuit board connection end is connected to the second frame mounting end to be connected to an element insertion part; and wherein the element insertion part is connected to the second frame feed part and embodied as a printed circuit board or a module for inserting a concentrated element. The loop antenna of claim 9, wherein a folded shape of the sub-frame surface is a left-right symmetry around the main frame surface and the folded surface faces a center of the frame, and the predetermined tilt angle is less than 90 °. The loop antenna of claim 9, wherein the first frame mounting end and the first circuit board connection end and the second Frame mounting end and the second circuit board connection end are assembled in an integrated form or a separate form. The loop antenna according to claim 11, wherein when the first frame mounting end and the first board connecting end are in the separated form, the first frame mounting end is inserted in a predetermined groove formed in the first board connecting end; and when the second frame attachment end and the second board connection end are in the separated form, the second frame attachment end is inserted in a predetermined groove formed in the second board connection end. The loop antenna according to any one of claims 9 to 12, wherein the first circuit board connection end has a first screw insertion hole formed in a face thereof for coupling with the feed circuit part and the second circuit board connection end has a second screw insertion hole formed in a face thereof for coupling with the element insertion part. The loop antenna according to claim 13, wherein the feed circuit part has a first screw through-hole formed in a face thereof for coupling to the first circuit board connection end and the element insertion part has a second screw through-hole formed in a face thereof for coupling to the second circuit board connection end. The loop antenna according to claim 14, wherein the feeding circuit part is inserted by a screw fastening method in which a screw is inserted into the first screw insertion hole formed in a surface of the first circuit board connecting end and the first screw through hole formed in the feeding circuit part, and then the screw is pulled from a back side of the first feeding circuit part Nut is tightened or the screw is attached to a first thread formed in an additional first supply circuit holder, is coupled to the first frame feed part; and the element insertion part by a screw fastening method in which a screw is inserted into the second screw insertion hole formed in a surface of the second circuit board connection end and the second screw through hole formed in the element insertion part, and then the screw is tightened from a back side of the supply circuit part by means of a nut or the screw is attached to a second thread formed in an additional second element insertion part holder, is coupled to the second frame feed part.

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