KR20080108802A - Circularly polarized antenna loaded rx and tx simultaneously for rfid reader, and antenna device using the same - Google Patents

Abstract

A circularly polarized antenna loaded Rx and Tx simultaneously for a RFID reader and antenna device using the same are provided to facilitate antenna assembly and reduce expenses so that mass production is possible. A circularly polarized antenna loaded Rx and Tx simultaneously for a RFID reader comprises: a radiator(10) for transmitting or receiving a circular polarized signal; a reflector(20) forming a predetermined interval of an air layer for improvement of impedance matching and axial ratio; and a feeder line part(30) for supplying electricity to the radiator. The radiator comprises that a via hole for inserting a shorting pin into a right center is formed and that the location of the feeding unit is formed from the right center to the direction of edge in different separation distance to X-axis and Y-axis.

Description

Circularly polarized antenna loaded Rx and Tx simultaneously for RFID reader, and antenna device using the same}

1 to 5 are plan views showing a PCB type radiator applied to a circular polarization antenna for an RFID reader according to a first embodiment of the present invention;

6 to 8 are plan views showing a metal-type radiator applied to a circular polarization antenna for an RFID reader according to a first embodiment of the present invention;

9 is a cross-sectional view of a circular polarization antenna for an RFID reader according to a first embodiment of the present invention;

10 is a plan view schematically showing a circular polarization antenna device for an RFID reader according to a second embodiment of the present invention;

11 is a perspective view, a plan view, and a sectional view of an antenna case main body applied to a circular polarization antenna device for an RFID reader according to a second embodiment of the present invention;

12 to 14 are perspective views showing various examples of a party wall installed in the antenna case body according to the second embodiment of the present invention;

15 is an external perspective view showing an example of an antenna case main body according to a second embodiment of the present invention;

16 is a reference view showing an external perspective view of a circular polarization antenna device for an RFID reader and an installation example according to a second embodiment of the present invention;

FIG. 17 is a plan view illustrating a radiator having a triangular wave-shaped cut surface among PCB-type radiators applied to a circular polarization antenna for an RFID reader according to a first embodiment of the present invention;

FIG. 18 is a plan view illustrating a radiator having a triangular wave-shaped cut surface among metal-type radiators applied to a circular polarization antenna for an RFID reader according to a first embodiment of the present invention.

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

10: radiator 11: via hole

12: feeder portion 13: square wave

14 sine wave 15 ring structure

16: square structure 20: reflector

21: air gap interval 30: feed line portion

31 connector cable 32 soldering

33: screw bolt

110: circular polarization antenna for the first RFID reader

120: circular polarization antenna for the second RFID reader

130: antenna case body 131: short circuit pin

132: first space 133: second space

134: party wall 135: window

140: mounting clamp 141: first tilt bracket

142: second tilt bracket 143: clamp body

150: reader

The present invention relates to a circular polarization antenna for an RFID reader and an antenna device using the same, and more particularly, to a radiator antenna having a simple structure in which electromagnetic coupling characteristics between a reflector and a radiator and impedance matching and axial ratio of maximum power transfer conditions are improved. The present invention relates to a circularly polarized antenna for RFID reader and an antenna device using the same.

The circular polarization antenna for the RFID reader of the present invention and the antenna device using the same are applicable to the UHF band of 900MHz as a single radiator antenna for radiation, and include metals of various materials such as PCB type or metal bodies including dielectric layers. Probe feeding is used for direct feeding, and it is possible to mass-produce transmit and receive antennas using a circularly polarized antenna of simple structure, as well as to embed a reader into the inner space of the boundary wall, Tilt the antenna freely in the up, down, left and right directions.

As is well known, RFID (Radio Frequency IDentification) is gaining importance as one of the major means for implementing ubiquitous computing systems, and according to recent trends, many researches have been conducted in the UHF band with excellent propagation characteristics. It is done.

The RFID is largely composed of a tag for storing recognition information and a reader for reading the information of the tag, and the tag and the reader respectively transmit information through an electromagnetic wave using an antenna provided therein. In addition, RFID is realized in various bands such as the HF band (13.56 MHz), the UHF band (860 MHz to 960 MHz), the ISM band (2.4 GHz), and the like.

However, the RFID of the HF band has a disadvantage that the recognition area of the antenna is very narrow due to the magnetic field coupling method, and the RFID of the ISM band is sensitive to the surrounding environment and thus the performance of the entire RFID system is variable. have.

On the other hand, UHF band RFID not only has excellent recognition rate and recognition distance of passive tags, but also has the advantage that it can recognize a large number of tags at high speed simultaneously using electromagnetic radiation method, and it is also very stable in the surrounding environment. It is known that the low cost production of tag chip is the most popular band among RFID use bands.

In such a UHF band RFID system, the role of the antenna connecting the reader and the tag is important. In particular, the passive RFID which receives power through the radio wave of the reader antenna is because the communication efficiency of the system is determined by the characteristics of the reader antenna. In other words, the antenna of an effective RFID reader should have almost no return loss in the operating frequency band, and should be designed to have good circular polarization (Axial Radio <3dB). It should have a radiation pattern required by, and should be made compact in order to make efficient use of a given space.

At present, many antennas for transmitting / receiving circularly polarized waves have been developed, but are not suitable for use as an antenna for an RFID reader. In other words, it is necessary to develop a reader / receiver antenna having an antenna characteristic suitable for RFID.

Conventional RFID reader antennas currently in commercial use are generally patch antennas using microstrips. These patch antennas have a narrow return loss bandwidth and circular polarization bandwidth, and are difficult to control the recognition region of the antenna, an important characteristic of the reader antenna. there is a problem.

Therefore, the RFID reader antenna needs excellent antenna characteristics, that is, excellent circular polarization radiation characteristics, high gain, wideband characteristics, beam width control, and small antenna production. This is required.

Accordingly, the present invention has been made to solve the conventional problems as described above, the object of the present invention is to assemble the antenna with a simple structure to improve the electromagnetic coupling characteristics, impedance matching, and axial ratio between the reflector and the radiator. The present invention also provides a circular polarization antenna for an RFID reader having an easy structure and mass production, and an antenna device using the same.

In addition, another object of the present invention is to provide a circular polarized antenna for RFID reader and an antenna device using the same to install the boundary wall between the circularly polarized antenna to be installed in the antenna device to set the beam width.

In addition, another object of the present invention is to provide a circular polarized antenna for an RFID reader and an antenna device using the same, by separating the left and right polarized waves through the boundary wall to reduce the coupling between the array elements, and to be physically strengthened. have.

In addition, the present invention is to provide a circular polarized antenna device for an RFID reader that can be installed by mounting the reader in the inner space of the boundary wall.

In addition, the present invention by installing the mounting clamp to the outside of the antenna case main body, the circular polarization for the RFID reader to be able to tilt freely tilting up and down, left and right antenna devices with a circular polarization radiator antenna for the first and second RFID reader An antenna device is provided.

The present invention for achieving the above object, the radiator for transmitting or receiving a circularly polarized signal; A reflector plate positioned below the radiator and spaced apart from the radiator in a vertical direction to form a predetermined air gap for improving impedance matching and axial ratio; And a feed line part for supplying electric power to the radiator, wherein the radiator has a rectangular shape, and forms a chamfer at both ends of the diagonal direction in a rectangular shape, and inserts a short pin at the center. A via hole is formed to be formed, and a position of a feeding point for impedance matching of a maximum power transfer condition is formed at different separation distances in the X and Y axes from the center to the edge. Disclosed is a circular polarization antenna for an RFID reader, characterized in that it has a predetermined specific height that satisfies the height of a feed part in a UHF (Ultra High Frequency) band.

Preferably, the feed portion is formed at an optimized position by setting the feed position at an offset within the range from 16 mm to 22 mm on the edge X axis and 47 mm to 53 mm on the Y axis from the center. .

In the feeding method to the radiator, it is preferable to use the probe feeding of the direct feeding method which directly connects the connector cable of the feeding line part to the position of the feeding part.

In this case, the direct connection of the probe feeding may be any one of a method of fixing to the connector cable by soldering, and a method of fixing through the fastening of a screw bolt to the connector cable.

Since the height of the reflector and the position of the feed section change the resonance frequency change, and the chamfer length of the reflector is an antenna having a circular polarization, and thus affects the axial ratio, so that between the reflector and the radiator It is preferable that the height of is determined in the range from 15 mm to 22 mm from the reflecting plate.

In addition, the radiator is configured in a chamfer shape in which both edges of the diagonal direction are cut to a predetermined length, and the electric field and magnetic field components of the lengths of the corners and the X and Y axes of the feeder are cut. A phase difference of 90 ° is realized by the combination of, and the chamfer portion further includes any one of a square wave shape, a sine wave shape, and a triangular wave shape, and from the influence of perturbation segments, It can be configured to implement broadband characteristics.

In this case, the square wave shape, the sine wave shape, and the triangular wave shape of the chamfer have an advantage of having broadband characteristics, are easy to design, and the electric length is long, thereby reducing the chamfer size.

Preferably, the feed part is any one of a ring structure, a square structure, and a polygonal structure in the form of an annular gap to offset the reactance component of the radiating element to increase the bandwidth. It can also be installed.

The radiator is preferably composed of any one of a PCB (Printed Circuit Board) type including a dielectric layer and a metal body of various materials.

In addition, the radiator is in the shape of a square, the overall size is composed of a range of 135mm ~ 145mm, the chamfer (chamfer) portion of both ends of the diagonal direction is preferably composed of a range of 35mm ~ 42mm.

The present invention for achieving the above object, a first polarization circular polarizer radiator antenna for generating a left polarization; A circularly polarized radiator antenna for a second RFID reader for generating postal waves; An antenna case body configured to separately mount and fix the circularly polarized radiator antennas for the first and second RFID readers, respectively; And a mounting clamp installed outside the antenna case main body and configured to adjust the tilt of the antenna case main body in a vertical direction or in a left and right direction.

The mounting clamp may include: first tilt brackets respectively installed at left and right end surfaces in the longitudinal direction of the antenna case main body; Second tilt brackets respectively provided at both front and rear end surfaces of the antenna case main body in a longitudinal direction; And a clamp body that may be engaged with any one or both of the first and second tilt brackets. At least one of the above, wherein the clamp body is engaged with any one of the first and second tilt brackets to adjust the tilt in the vertical or horizontal direction, or both the first and second tilt brackets It is preferable that the fastening is configured to adjust the tilt in the up, down, left and right directions.

The antenna case main body has a rectangular enclosure having an internal space, and includes first and second spaces in which the circularly polarized radiator antennas for the first and second RFID readers are separately installed, respectively. A boundary wall that maintains a predetermined distance between the two spaces, the boundary wall isolates left and right waves of the circularly polarized radiator antennas for the first and second RFID readers. It acts as a physical reinforcement.

Preferably, the beam width of the radiation pattern is adjusted in accordance with a predetermined spacing adjustment of the boundary wall held between the first and second spaces.

In addition, the boundary wall may further form at least one or more windows on each side wall surface of the first and second spaces facing each other, and may also be configured in an obtuse bending (roof shape).

Preferably, a reader may be inserted into and installed into the interior space of the boundary wall.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

1 to 5 are plan views showing an example of a PCB-type radiator applied to a circular polarization antenna for an RFID reader according to a first embodiment of the present invention, and FIGS. 6 to 8 are views according to the first embodiment of the present invention. 9 is a plan view showing an example of a metal-type radiator applied to a circular polarization antenna for an RFID reader, and FIG. 9 is a cross-sectional view of the circular polarization antenna for an RFID reader according to the first embodiment of the present invention.

Circular polarization antenna for RFID reader according to the first embodiment of the present invention, as shown in Figure 9, the radiator 10 for transmitting or receiving a circularly polarized signal, and is located below the radiator 10, A reflector plate 20 spaced apart from the radiator 10 in a vertical direction to form a predetermined air gap 21 for improving impedance matching and axial ratio, and a feed line unit for supplying power to the radiator 10 ( 30).

The radiator 10 may be a printed circuit board (PCB) type including a dielectric layer and metal materials of various materials, in particular, plated Al and Cu metal materials.

As shown in FIGS. 1 to 8, the radiator 10 is configured to form a chamfer (chamfer) at both ends of the diagonal direction in a rectangular shape. In addition, a via hole 11 for inserting a short pin 131 in the center is formed, and a position of the feeding part 12 for impedance matching of the maximum power transfer condition is formed. From the center to the edge at the range of 16mm to 22mm on the X axis and 47mm to 53mm on the Y axis.

This is because the current is maximized at the center edge portion of the radiator 10 and the resistance is in an open state, and the impedance is lowered toward the center, and the center point becomes a short state with little current.

In addition, the height of the feed section 12 is important for impedance matching and axial ratio, the height setting of the feed section 12 is lower the antenna radiation efficiency as the height between the radiator 10 and GND is smaller.

That is, since the + charge of the radiator 10 and the-charge of the GND are attracted, the height adjustment between the GND and the radiator 10 is required to improve the radiation characteristics of the antenna, the reflector 20 and the radiator The air gaps 21 between 10 are required to maintain a predetermined gap in order to improve the impedance matching and the axial ratio described above.

In this case, the height between the reflecting plate 20 and the radiator 10, that is, the air gap 21 is determined in the range of 15mm ~ 22mm from the reflecting plate 20.

In addition, the radiator 10 has a shorting pin 131 inserted into the via hole 11 formed at the center of the radiator 10, thereby forming a capacitance component between the reflector plate 20 and the radiator 10 and the shorting pin 131. Broadband characteristics are realized by combining inductance components.

The feeding method to the radiator 10 uses probe feeding of a direct feeding method that directly connects the connector cable 31 of the feed line part 30 to the position of the feeding part 12. do.

At this time, as a direct connection method as shown in Fig. 9 (a), a method of fixing to the connector cable 31 by soldering (solder), and as shown in Fig. 9 (b) Likewise, methods of fixing the screw bolt 33 to the connector cable 31 may be used.

In addition, the radiator 10 has a chamfer shape in which both edge portions of the diagonal direction are cut to a predetermined length, and thus the length of the corner cut portion, the electric field of the X-axis and Y-axis of the power supply unit 12, and A 90 ° phase difference is achieved by harmonizing the magnetic field components.

Here, the chamfer portion of the radiator 10 may further include a square wave shape, as shown in FIGS. 3 and 7, and also shown in FIGS. 4 and 8. As shown, it may further comprise a sine wave (14) form. In addition, as illustrated in FIGS. 17 and 18, the chamfer portion of the radiator 10 may further include a triangular wave shape. This enables the implementation of broadband characteristics due to parasitic radiation under the influence of perturbation segments.

In this case, the square wave 13 shape and the sinusoidal wave shape have an advantage of having a broadband characteristic, and are easy to design and have an electric length, thereby providing an advantage of reducing the size of a chamfer.

As shown in FIGS. 5 and 6, the feed part 12 has a ring structure 15 in the form of an annular gap to offset the reactance component of the radiating element to increase the bandwidth. And a square structure 16 may be further mounted, and in addition, a polygonal structure (not shown) may be used.

In addition, the radiator 10 is a square, the overall size is composed of a range of 135mm ~ 145mm, the chamfer (chamfer) portion of both ends of the diagonal direction is preferably composed of a range of 35mm ~ 42mm, 12) is optimized by offsetting the feed position within the range of 16mm to 22mm in the X-axis and 47mm to 53mm in the Y-axis based on the exact center position of the short pin 131 (short pin). Allow impedance matching to be implemented.

1 shows a PCB-type radiator applied to a circularly polarized antenna for an RFID reader according to a first embodiment of the present invention. As a specific embodiment, a square of 140 mm × 140 mm in length, and a chamfer portion Horizontal edges are cut diagonally at a position of 37 mm × 37 mm. And the position of the feed part 12 was comprised so that it might be located at the coordinate point of 19 mm horizontally 50 mm x left-right vertically in the center of the radiator 10 in the downward direction.

2 shows a PCB-type radiator applied to a circular polarization antenna for an RFID reader according to a first embodiment of the present invention. As a specific embodiment, the size of the radiator 10 is 144 mm × 144 mm. Chamfer (Chamfer) portion is cut diagonally at the position of both ends of the horizontal 38mm × 38mm vertical. And the position of the feed part 12 was comprised so that it might be located at the coordinate point of 19 mm horizontally 50 mm x left-right vertically in the center of the radiator 10 in the downward direction.

10 is a plan view schematically illustrating a circular polarization antenna device for an RFID reader according to a second embodiment of the present invention, and FIG. 11 is applied to a circular polarization antenna device for an RFID reader according to a second embodiment of the present invention. 12 and 14 are perspective views showing examples of various forms of a boundary wall installed in the antenna case body according to the second embodiment of the present invention. An external perspective view showing an example of an antenna case body according to a second embodiment of the present invention, Figure 16 is an external perspective view of a circular polarization antenna device for an RFID reader according to a second embodiment of the present invention, and a reference diagram showing an installation example to be.

As illustrated, the circular polarization antenna device for an RFID reader includes a circular polarization radiator antenna 110 for a first RFID reader generating a left polarization, a circular polarization radiator antenna 120 for a second RFID reader generating a right polarization, and The antenna case body 130 and the antenna case body 130 for separately mounting and fixing the first and second circularly polarized radiator antennas 110 and 120 for the RFID reader, respectively, are installed outside the antenna case body. It is configured to include a mounting clamp 140 for adjusting the tilt (130) in the vertical or horizontal direction (130).

The circularly polarized radiator antennas 110 and 120 for the first and second RFID readers generate left and right polarized waves by the positions of the feed line units 30 having different lengths.

The circular polarization antenna device for an RFID reader according to the second embodiment of the present invention includes a mounting clamp 140 installed at a specific mounting location as a separate antenna for transmission and reception.

In this case, the circularly polarized radiator antennas 110 and 120 for the first and second RFID readers are configured of the circularly polarized antenna for the RFID reader described in the first embodiment of the present invention, that is, the via hole 11 and the power supply unit 12. Since the configuration of the radiator 10, the reflector plate 20, and the feed line unit 30 having the position of the same as the connection and function between the respective detailed configuration will be omitted.

Hereinafter, the operation and configuration of the case structure and the mounting clamp structure in which the circularly polarized radiator antennas 110 and 120 for the first and second RFID readers are installed will be described in detail. In this case, in describing the antenna case structure of the present invention, detailed descriptions of various protrusions installed to support the antenna will be omitted.

First, as shown in FIGS. 11 to 14, the antenna case body 130 is configured in a rectangular shape having an internal space.

In addition, the antenna case body 130 includes first and second spaces 132 and 133 in which the circularly polarized radiator antennas 110 and 120 for the first and second RFID readers are separately installed, respectively. A boundary wall 134 is formed to maintain a predetermined gap between the first and second spaces 132 and 133.

Here, the boundary wall 134 functions to isolate left and right polarizations of the circularly polarized radiator antennas 110 and 120 for the first and second RFID readers, and also acts as a physical reinforcing material.

In addition, the beam width of the radiation pattern is adjusted according to a predetermined gap adjustment of the boundary wall 134 held between the first and second spaces 132 and 133.

Table 1 below shows beam width values adjusted according to the separation distance at which the boundary wall 134 is installed.

900 MHz band Remarks When there is no boundary wall 63 ° PCB Type Boundary wall separation distance 60mm 64 ° PCB Type Boundary wall separation distance 75mm 60 ° PCB Type Boundary wall separation distance 70mm 58 ° Metal body type

In addition, the boundary wall 134 may further form at least one window 135 on each side wall surface of the first and second spaces 132 and 133 facing each other, as shown in FIG. 12. . In addition, the boundary wall 134 may be configured as an obtuse bending (roof shape), as shown in FIG.

The boundary wall 134 may be configured to slide left and right as needed. This makes it possible to adjust the position of the boundary wall in order to set the optimum position.

The antenna case body 130 may be divided into a lower case having an inner space and a lid covering the upper portion, and the external form of the antenna case body 130 may be implemented in various forms by a designer. .

FIG. 14 is an example of the boundary wall 134 installed in the antenna case body 130 according to the second embodiment of the present invention, and shows a form in which a reader 150 is inserted into and installed in an internal space. Here, the reader 150 may be installed in the interior space of the boundary wall 134 of various shapes as shown in FIGS. 11 to 14.

In addition, the reader 150 may be installed separately on the rear side as well as the antenna case body 130.

15 is an external perspective view showing an example of an antenna case body according to a second embodiment of the present invention.

As shown in the figure, an acrylic material of transparent material is placed on the upper part of the antenna case body 130, that is, on the radiator 10, as a cover (not shown), and the U-shaped bracket is a space where the boundary wall 134 is located. This can be installed. At this time, the U-shaped bracket may be replaced by the second tilt bracket 142, which will be described later, or may be provided separately.

16 is a reference diagram showing an external perspective view of a circular polarization antenna device for an RFID reader and an example of installation according to a second embodiment of the present invention.

As shown, the mounting clamp 140 includes a first tilt bracket 141, a second tilt bracket 142, and a clamp body 143.

The first tilt bracket 141 is installed on both left and right end surfaces of the antenna case body 130 in the longitudinal direction, and the second tilt bracket 142 is disposed in the longitudinal direction of the antenna case body 130. It is installed on both front and rear sections.

The clamp body 143 is fastened to only one of the first and second tilt brackets 141 and 142 may be configured to adjust the tilt in the vertical or horizontal direction. At this time, the other end of the clamp body 143 may be attached to a specific mounting location, as shown in FIG.

The mounting clamp 140 is capable of vertical adjustment in the vertical direction and horizontal adjustment in the left and right direction, vertical or horizontal adjustment is also depending on the case where the antenna case body 130 is installed vertically or installed horizontally Can be applied.

In addition, the clamp body 143 may be coupled to both the first and second tilt brackets 141 and 142 to be configured to adjust the tilt in the up, down, left and right directions, and the other end of the clamp body 143 Is used to attach to a specific mounting location.

In this case, the first tilt bracket 141 and the second tilt bracket 142 may be connected to the clamp body 143 by adjusting the length, and the other method may be adjusted vertically, horizontally, vertically or horizontally. It can also be configured by applying a spherical clamp device (not shown).

Although the present invention has been described in more detail with reference to the embodiments, the present invention is not necessarily limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

According to the above-described circular polarization antenna for an RFID reader and an antenna device using the same according to the present invention, a single radiator antenna for radiation may be a PCB (Printed Circuit Board) type including a dielectric layer or plated aluminum or copper material. It is possible to apply to a metal body including, by implementing a circular polarized antenna of a simple structure using a reflector and a connector, the antenna assembly is easy, cost is reduced, and mass production is provided.

In addition, the present invention forms a via hole in the center of the radiator to provide a short pin (Short Pin) by providing a stable holding effect for the coupling of the radiator and the reflector physically, and solves the problem of narrow band functionally There is an effect to obtain the characteristics of the optimal circular polarization.

In addition, the present invention has the effect of suppressing surface waves and removing ripples on the radiation pattern by spaced apart in the vertical direction between the reflecting plate and the radiator.

In addition, the present invention has an effect that the width of the beam radiated from the radiator can be adjusted by a predetermined distance of the boundary wall by providing a party wall between the circularly polarized antennas in the configuration of the antenna device. This provides the effect of reducing the beam width and increasing the gain of the antenna by adjusting the distance between the party walls.

In addition, the present invention has the effect of isolating the left and right polarization through the boundary wall, as well as providing a role of a physical reinforcement, and also by using a direct power supply method compared to the conventional power divider using a loss This is small and has the effect of improving the gain of the antenna.

In addition, the present invention can be mounted by mounting the reader into the interior space of the boundary wall, it provides an effect that can be freely adjusted tilt in the vertical direction of the antenna installed through the mounting clamp.

Claims (16)

A radiator for transmitting or receiving circular polarized signals; A reflector plate positioned below the radiator and spaced apart from the radiator in a vertical direction to form a predetermined air gap for improving impedance matching and axial ratio; And A feed line unit for supplying power to the radiator; The radiator has a rectangular shape and forms a chamfer shape at both ends of the diagonal direction, forms a via hole for inserting a short pin at the center, and provides a maximum power transfer condition. The position of the feeding point for impedance matching is formed at different separation distances in the X-axis and Y-axis in the direction from the center to the edge, and UHF (Ultra High Frequency) with respect to the feeding point height. A circular polarized antenna for an RFID reader, on which Rx and Tx are simultaneously mounted, characterized by having a predetermined specific height satisfied in a band. The method of claim 1, In the feeding method to the radiator, Rx and Tx are mounted at the same time, using a probe feeding of a direct feeding method that directly connects the connector cable of the feeding line part to the position of the feeding part. Circularly polarized antenna for RFID readers. The method of claim 1, The height between the reflector and the radiator is a circular polarized antenna for RFID reader, Rx, Tx is mounted at the same time, characterized in that configured to have a range of 15mm ~ 22mm from the reflector. The method of claim 2, The direct connection of the probe feeding is any one of the method of fixing to the connector cable by soldering, and the method of fixing by fastening the screw bolt to the connector cable, Rx, Tx is mounted at the same time Circularly polarized antenna for RFID readers. The method of claim 1, The radiator is formed in a chamfer shape in which both edges of the diagonal direction are cut to a predetermined length, so that the length of the corner cut portion is harmonized with the electric field and magnetic field components of the X-axis and Y-axis of the feeder. Phase difference of 90 ° The chamfer further includes any one of a square wave shape, a sinusoidal wave shape, and a triangular wave shape, and Rx and Tx are simultaneously loaded with RFID, characterized in that the broadband characteristics due to parasitic radiation are implemented under the influence of perturbation segments. Circularly polarized antenna for reader. The method of claim 1, The feeding part is in the form of an annular gap for canceling the reactance component of the radiating element to increase the bandwidth, and further comprising one of a ring structure, a square structure, and a polygonal structure. Circular polarization antenna for RFID reader which is equipped with Rx and Tx at the same time. The method according to any one of claims 1 to 6, The radiator is a circular polarization antenna for an RFID reader, on which Rx and Tx are simultaneously mounted, comprising one of a PCB (Printed Circuit Board) type including a dielectric layer and a metal body including plated aluminum or copper. . The method of claim 7, wherein The radiator is a square, the overall size is composed of a range of 135mm ~ 145mm, and the chamfer (chamfer) of the corners of both ends of the diagonal direction is configured in the range of 35mm ~ 42mm RFID, Rx, Tx is mounted simultaneously Circularly polarized antenna for readers. The method of claim 8, The position of the feed portion is optimized impedance matching by offsetting the feed position within the range of 16mm to 22mm on the X axis and 47mm to 53mm on the Y axis with respect to the exact center position of the short pin. Circular polarization antenna for RFID reader, Rx, Tx is mounted at the same time, characterized in that to implement. A circularly polarized radiator antenna for a first RFID reader for generating left polarization; A circularly polarized radiator antenna for a second RFID reader for generating postal waves; An antenna case body configured to separately mount and fix the circularly polarized radiator antennas for the first and second RFID readers, respectively; And A mounting clamp installed outside the antenna case main body to adjust the tilt of the antenna case main body in a vertical direction or a horizontal direction; Rx, Tx including a circular polarized antenna for RFID reader is mounted at the same time. The method of claim 10, The mounting clamp may include: first tilt brackets respectively installed at left and right end surfaces in the longitudinal direction of the antenna case main body; Second tilt brackets respectively provided at both front and rear end surfaces of the antenna case main body in a longitudinal direction; And A clamp body that may be engaged with any one or both of the first and second tilt brackets; At least one or more of The clamp body is engaged with any one of the first and second tilt brackets to adjust the tilt in the up and down or left and right directions, or is engaged with both the first and second tilt brackets to adjust the tilt in the up, down, left and right directions. Circular polarized antenna for RFID reader, Rx, Tx is mounted at the same time, characterized in that configured to. The method of claim 11, The antenna case main body has a rectangular enclosure having an internal space, and includes first and second spaces in which the circular polarization antennas for the first and second RFID readers are separately installed, respectively, and the first and second spaces. A party wall that maintains a predetermined spacing between the spaces; The boundary wall isolates the left polarization and the postal wave of the circular polarization antennas for the first and second RFID readers, and acts as a physical reinforcing material. antenna. The method of claim 12, And a beam width of the radiation pattern is adjusted in accordance with a predetermined distance adjustment of the boundary wall held between the first and second spaces. The method of claim 13, The boundary wall further includes at least one window formed on each side wall surface of the first and second spaces facing each other, wherein the Rx and the Tx are simultaneously mounted. The method of claim 14, The boundary wall is a circular polarization antenna for an RFID reader on which Rx and Tx are mounted at the same time, wherein the boundary wall is configured in an obtuse bending shape. The method according to any one of claims 10 to 15, A circular polarized antenna for RFID readers, in which Rx and Tx are mounted at the same time, characterized in that a reader is inserted into and installed in the inner space of the boundary wall.

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