JP2020072389A - Antenna device - Google Patents

Abstract

To provide a technique that prevents the gain of an antenna for far-field communication from declining due to an antenna for near-field communication.SOLUTION: An antenna device (2) includes a first antenna unit (12), a second antenna unit (26), and a signal combination circuit (18). The first antenna unit is composed of a patch antenna and has two feeding points. The second antenna unit is composed of a strip line and has one feeding point. The signal combination circuit is composed of a hybrid ring having two common ends (To1 and To2) and two distribution ends (Ti). The two distribution ends are connected with the two feeding points of the first antenna unit. The first common end (To1) is used as an input/output end (Tx) of signals for the first antenna unit and the second antenna unit. The second common end (To2) is connected with a feeding point of the second antenna unit and a termination resistor (44).SELECTED DRAWING: Figure 2

Description

  The present invention relates to an antenna device that reads identification information from an RF tag.

  Patent Document 1 discloses a far-field communication antenna that uses a patch antenna and a near-field communication antenna that uses a stripline having a meander line structure as an antenna device used for reading identification information wirelessly transmitted from an RF tag. The combination is described.

  In this conventional device, the near-field communication antenna is connected in series to the output end of the hybrid ring that synthesizes the received signals from the two feeding points of the far-field communication antenna, so that the received signals from both antennas are connected to each other. It is configured to receive without switching the operation.

JP, 2017-17380, A

  However, in the conventional device described in Patent Document 1, the near-field communication antenna viewed from the far-field communication antenna is merely a transmission path, and its transmission loss reduces the gain of the far-field communication antenna. There was a problem.

  An object of the present disclosure is to provide a technique for suppressing a decrease in gain of a far field communication antenna due to a near field communication antenna.

  One aspect of the present disclosure is an antenna device formed by a conductor pattern on a dielectric substrate, which includes a first antenna unit, a second antenna unit, and a signal combining circuit. The first antenna unit is composed of a patch antenna and has two feeding points. The second antenna unit is configured by a strip line and has one feeding point. The signal combining circuit is configured by using a hybrid ring having two common ends and two distribution ends, two feeding points of the first antenna unit are connected to the two distribution ends, and one of the two common ends is included. One side is used as a first common end and the other side is used as a second common end, and the first common end is used as a signal input / output end for the first antenna part and the second antenna part, and the second common end is connected to the second antenna part. Is connected to the feeding point and the terminating resistor.

  In this case, since the received signal from the first antenna unit synthesized by the signal synthesizing circuit can be directly output without passing through the second antenna unit, the gain of the first antenna unit is not reduced and Two antenna parts can be connected.

  Further, in particular, since the antenna device of the present invention is configured as a sheet-shaped planar antenna by forming conductor patterns forming two types of antenna parts on a substrate, it is used by mounting it on a cash register. And can be easily installed on the cash register.

  In one aspect of the present disclosure, the strip line forming the second antenna unit may have a meander line structure. Further, the interval between the striplines arranged adjacent to each other by forming the meander line structure may be set to be shorter than the shortest width of the outer shape of the opening surface of the communication target antenna.

  In this case, it is possible not only to expand the area where near-field communication can be performed on the substrate surface of the dielectric substrate, but also to cope with near-field communication with a plurality of types of communication target antennas having different opening surface shapes.

In one aspect of the present disclosure, the second antenna unit may have a structure in which the non-feed end of the strip line is opened.
In this case, as compared with the case where the non-feeding end of the strip line is short-circuited or terminated, it is possible to suppress a decrease in gain of the first antenna unit due to the connection of the first antenna unit.

  In one aspect of the present disclosure, the dielectric substrate has a conductor pattern that forms a patch antenna serving as a radiator of the first antenna unit formed on a substrate surface that is one substrate surface, and a substrate that is the other substrate surface. A conductor pattern serving as a ground may be formed on the back surface. A plurality of slits may be provided in the conductor pattern forming the patch antenna. The plurality of slits may be arranged such that the width of the first antenna section divided by the slits is shorter than the shortest width of the outer shape of the opening surface of the communication target antenna.

  In this case, the conductor pattern forming the first antenna portion serves as a near-field and near-field antenna because the narrow portion separated by the slit functions as a near-field antenna.

  One aspect of the present disclosure may further include an impedance converter including a microstrip line that connects two feeding points of the first antenna unit and two combining ends of the signal combining circuit.

  In this case, in the conductor pattern forming the first antenna unit, even if the feeding point cannot be set at a position where the same impedance dance characteristic as the synthesizing end of the signal synthesizing circuit can be obtained, the signal at the synthesizing end and the feeding point cannot be set. It is possible to suppress reflection and the like and suitably connect the combined end and the feeding point.

In one aspect of the present disclosure, the second antenna unit may be arranged around the first antenna unit.
In this case, near field communication can be performed with the communication target antenna around the first antenna unit, so that the identification information can be more reliably read from the RF tag.

In one aspect of the present disclosure, the hybrid ring forming the signal combining circuit may be bent and arranged in an L shape along one corner of the dielectric substrate.
In this case, the hybrid ring can be formed in a vacant area around the first antenna portion, and it is not necessary to increase the substrate area of the dielectric substrate to form the hybrid ring, so that the antenna device can be downsized. You can

It is explanatory drawing showing the state which looked at the antenna device from the outer peripheral edge side of the dielectric substrate. It is explanatory drawing showing the conductor pattern formed in the board | substrate surface of the dielectric substrate of an antenna device. It is explanatory drawing showing the structure of the conductor pattern of a signal synthetic | combination circuit of an antenna device, and the connection part of a coaxial cable. It is a block diagram which shows the connection relation of each part which comprises an antenna device. It is explanatory drawing showing the electric conductor pattern of the signal synthetic | combination circuit periphery in a comparative example. It is a block diagram which shows the connection relation of each part in a comparative example. It is a characteristic view showing the gain of the antenna device when the non-feeding end of the second antenna unit is open. It is a characteristic view showing the gain of the antenna device when the non-feeding end of the second antenna unit is short-circuited. It is a characteristic view showing the gain of an antenna device when the non-feeding end of the 2nd antenna part is a termination.

Embodiments of the present invention will be described below with reference to the drawings.
[1. overall structure]
The antenna device 2 of the present embodiment is placed on a cash register table of a store or the like and is used to read identification information from an RF tag attached to an article such as a commodity, as shown in FIG. A substrate (hereinafter referred to as a dielectric substrate) 10 formed of a dielectric that serves as an antenna device body is provided.

  In the dielectric substrate 10, a conductor pattern forming a patch antenna or the like serving as a radiator is formed on one substrate surface (hereinafter, substrate front surface) 10a, and the other substrate surface (hereinafter, substrate rear surface) 10b is substantially entirely formed. A conductor pattern serving as a ground (that is, a ground pattern) is formed on. Therefore, the dielectric substrate 10 functions as a flat antenna that can radiate radio waves from the substrate surface 10a.

  The dielectric substrate 10 has a substantially square planar shape (see FIG. 2) as viewed from above in FIG. 1, and a connecting portion 22 is formed at one of the four corners. A coaxial cable 30 for inputting / outputting a transmission / reception signal is fixed to the connection portion 22 via a crimp terminal 42.

  The center conductor 32 of the coaxial cable 30 is connected (soldered) to the output end of the conductor pattern formed on the substrate surface 10a, and the outer conductor 34 is a ground pattern formed on the outer peripheral portion of the substrate surface of the substrate surface 10a. 28 (soldering).

  In the dielectric substrate 10, the connection portion 22 is covered with a sheet-shaped shock absorbing material 52 from the substrate surface 10a side. Further, the entire dielectric substrate 10 is covered with a synthetic resin protective sheet 50.

High-performance urethane foam (microcell polymer sheet) is used for the shock absorbing material 52, and a vinyl chloride sheet is used for the protective sheet 50.
The protective sheet 50 covers the dielectric substrate 10 from both sides with two sheets of material, and presses the two sheets of material together at the outer peripheral portion of the dielectric substrate 10 to store the entire dielectric substrate 10. Protect.

  When two sheet materials are pressure-bonded, one sheet material is arranged along the substrate back surface 10b, and the other sheet material is covered from the substrate front surface 10a side, so that the pressure-bonded portion is in the thickness direction of the dielectric substrate 10. It is designed to be located below the center.

  This is because when the antenna device 2 is placed on the cash register, the pressure-bonded portion of the protective sheet 50 is along the plate surface of the cash register. This prevents the pressure-bonded portion of the protective sheet 50 from becoming an obstacle when an operator moves a product on the cash register.

[2. Conductor pattern on the substrate surface]
Next, the conductor pattern formed on the substrate surface 10a of the dielectric substrate 10 will be described.

  As shown in FIG. 2, the first antenna portion 12 is formed on the substrate surface 10 a of the dielectric substrate 10 at approximately the center. The first antenna unit 12 is a conductor pattern having a substantially square outer shape, which serves as a radiator of the patch antenna.

  The first antenna section 12 has a central pattern removal section 13 in which a conductor pattern is removed, which is formed in a rectangular shape similar to the first antenna section 12 in a central portion thereof. This is because in the patch antenna, the central portion of the patch forming the radiator has a small influence on the antenna characteristics even if the pattern is removed.

  In addition, in the first antenna unit 12, between the outer periphery of the first antenna unit 12 and the central pattern removal unit 13, double ring-shaped slits 14a and 14b having a shape similar to the outer periphery of the first antenna unit 12 are formed. Are formed.

  As a result, the first antenna unit 12 has a triple ring-shaped conductor pattern (hereinafter, ring-shaped pattern) divided by the two ring-shaped slits 14a and 14b. The ring-shaped slits 14a and 14b are arranged at predetermined intervals so that the width L of the ring-shaped pattern is shorter than the shortest width of the outer shape of the opening surface of the communication target antenna provided in the RF tag. It

  The ring-shaped slits 14a and 14b are divided at the centers of the first antenna unit 12 in the vertical direction and the horizontal direction, respectively. That is, each of the ring-shaped slits 14 a and 14 b is composed of four slits each having an L-shape along the two sides of the outer peripheral corner of the first antenna unit 12. Further, the triple ring-shaped patterns in the first antenna unit 12 are electrically connected to each other at the dividing points of the ring-shaped slits 14a and 14b. Hereinafter, a cross-shaped conductor pattern that divides the ring-shaped slits 14a and 14b and crosses the triple ring-shaped pattern in the vertical and horizontal directions is referred to as a cross pattern.

  The reason why the cross pattern is provided in the first antenna unit 12 is that if the cross pattern is omitted, the first antenna unit 12 functions as a loop antenna and does not function as a patch antenna. That is, the cross pattern secures the radiation performance in the vertical direction and the horizontal direction, which are required for the patch antenna and are orthogonal to each other. In the first antenna unit 12 shown in FIG. 2, the central pattern removing unit 13 is not provided with the cross pattern, but it goes without saying that the central pattern removing unit 13 may be provided with the cross pattern.

  The first antenna unit 12 thus configured basically functions as an antenna for the far field, but also functions as an antenna for the near field because the ring-shaped slits 14a and 14b are provided. To do.

  That is, when the entire area of the patch antenna is formed of a conductor pattern and the RF tag is located near the patch antenna, the resonance frequency of the communication target antenna provided in the RF tag shifts. Then, the reading device (reader / writer) side connected via the coaxial cable 30 cannot read the identification information from the RF tag and cannot function as a near-field antenna. On the other hand, when the ring-shaped slits 14a and 14b are provided like the first antenna unit 12, the deviation of the resonance frequency of the communication target antenna is suppressed, and therefore the reading device reads the identification information from the RF tag. It becomes possible to function as an antenna for near field.

  There are a plurality of types of RF tags to be read, which have different sizes, and the sizes of the antennas to be communicated included in the RF tags also vary accordingly. Therefore, the width L of the ring-shaped pattern of the first antenna unit 12 that is divided by the ring-shaped slits 14a and 14b is based on the antenna having the smallest outer shape of the opening surface among the communication target antennas having different sizes. Is set as.

  As a result, the antenna device 2 can perform far-field communication and near-field communication with all the communication target antennas provided in the RF tag that is the target of reading the identification information by the first antenna unit 12. Becomes

  The first antenna unit 12 has a feeding point at each of the center portions of two adjacent sides on the outer periphery of the first antenna unit 12 so that the patch antenna realized by the first antenna unit 12 functions as a circularly polarized wave antenna. P is provided.

  This is because a linearly polarized antenna is used as a communication target antenna in the RF tag, and the antenna device 2 does not depend on the RF tag regardless of the positional relationship between the antenna device 2 and the RF tag. This is to enable far field communication with the communication target antenna.

  The two feeding points P included in the first antenna unit 12 are individually connected to the signal combining circuit 18 via the two impedance converters 16 formed on the same substrate surface 10a as the first antenna unit 12.

  The impedance converter 16 includes a high-impedance microstrip line 16a connected to each feeding point P, a specific impedance (for example, 50Ω) microstrip line 16c connected to the signal synthesis circuit 18, and a microstrip line 16a. 16c, and a microstrip line 16b having an impedance in between.

  The length of each of the microstrip lines 16a to 16c is a quarter (λ / 4) of the wavelength λ of the center frequency of the communication frequency with the RF tag (900 MHz band in this embodiment). Is set to. The wavelength λ is a value that takes the wavelength shortening rate into consideration. Hereinafter, the same applies to the wavelengths used when defining the length in the present invention and the specification.

  The signal combining circuit 18 is a hybrid ring having two combining ends Ti, Ti to which the pair of impedance converters 16 (specifically, a microstrip line 16c having a specific impedance) are connected, and two common ends To1, To2. Consists of

  The hybrid ring forming the signal combining circuit 18 is formed of a conductor pattern (here, a microstrip line) formed on the same substrate surface 10a as the first antenna unit 12. A hybrid ring of this type is usually formed in a rectangular shape, but in the present embodiment, the substrate surface 10a around the first antenna unit 12 is effectively used, and the coaxial cable 30 is provided at a corner of the dielectric substrate 10. In order to form the connecting portion 22 of the above, it is deformed into an L shape.

  The first common end To1 that is one common end of the hybrid ring extends to the connection portion 22 of the coaxial cable 30. Hereinafter, the end portion of the conductor pattern that extends to the connection portion 22 and is connected to the coaxial cable 30 is referred to as a connection end Tx.

  The second common end To2, which is the other common end of the hybrid ring, is grounded via the terminating resistor 44 to the ground pattern 28 formed on the outer peripheral portion of the substrate surface 10a of the dielectric substrate 10. The ground pattern 28 is connected to the conductor pattern formed on the back surface 10b of the substrate through a through hole. Further, the second common end To2 is connected to the second antenna section 26 which is a microstrip line formed so as to surround the first antenna section 12 on the substrate surface 10a. Below, of both ends of the second antenna unit 26, the side connected to the second common end To2 is referred to as the feeding end, and the other side is referred to as the non-feeding end. The non-feeding end of the second antenna unit 26 is located near the first common end To1 and is in an open state. The non-feeding end of the second antenna unit 26 may be short-circuited or terminated.

  The microstrip line forming the second antenna unit 26 has a meander line structure in which the U-shaped bending is repeated, and the space between the microstrip lines adjacent to each other by bending is equal to the opening surface of the communication target antenna. It is set to be shorter than the shortest width of the outer shape.

  By including the second antenna unit 26 as described above, according to the antenna device 2, near-field communication is performed not only with the first antenna unit 12 but also with the communication target antenna not only around the first antenna unit 12. it can.

[3. Connection part]
Next, the connecting portion 22 of the coaxial cable 30 formed at the corner of the dielectric substrate 10 will be described. FIG. 3 is a plan view of a corner portion of the dielectric substrate 10 provided with the connection portion 22 as viewed from the substrate surface 10a side.

  As shown in FIG. 3, through holes 24 for fixing the crimp terminals 42 are formed in the ground patterns 28 at the corners of the dielectric substrate 10, and through the eyelets 46 are formed in the through holes 24. Then, the crimp terminal 42 is fixed.

  In the connection portion 22, the corner portion of the dielectric substrate 10 may be cut out so that the coaxial cable 30 can be fixed via the crimp terminal 42. Further, in the dielectric substrate 10, in a state where the coaxial cable 30 is fixed by the crimp terminal 42, a notch for passing the outer conductor 34 is provided at a portion where the outer conductor 34 is arranged at the tip. Good.

  A ground pattern 28 is formed on the dielectric substrate 10 so as to sandwich a portion where the outer conductor 34 is arranged, and the outer conductor 34 of the coaxial cable 30 is soldered to the ground pattern 28.

  A tip end of a microstrip line extending from the first common end To is arranged at a further tip end portion of the coaxial cable 30 fixed to a corner portion of the dielectric substrate 10, and the microstrip line has a coaxial tip end. The center conductor 32 of the cable 30 is soldered.

  A recess for accommodating the terminating resistor 44 formed of a chip component may be formed in the portion of the dielectric substrate 10 to which the terminating resistor 44 is attached. The recess is for suppressing the amount of protrusion from the substrate surface 10a due to its thickness when the terminating resistor 44 is mounted on the dielectric substrate 10. Note that this configuration is an example, and a through hole capable of housing the terminating resistor 44 may be provided instead of the recess.

[4. Measurement]
7 to 9 show the results of measurement of the frequency vs. gain characteristics of the antenna device 2 (hereinafter, referred to as an example) of the present embodiment configured as described above. Here, the measurement result of the comparative example is also shown using the antenna device shown in Patent Document 1 as a comparative example.

  In the embodiment, the connection relationship among the first antenna unit 12, the signal synthesizing circuit 18, the second antenna unit 26, and the terminating resistor 44 is as shown in FIG. 4, and the first common end To1 remains unchanged. The terminating resistor 44 and the second antenna unit 26 are connected to the connection end Tx, and the second common end To2.

  On the other hand, in the comparative example, as shown in FIGS. 5 and 6, the terminating resistor 44 is connected to the first common end To1, the feeding end of the second antenna unit 26 is connected to the second common end To2, and the second antenna is connected. The non-power feeding end of the portion 26 is a connection end Tx.

That is, the example and the comparative example are different in the position where the second antenna portion 26 is connected and the position of the connection end Tx where the coaxial cable 30 is connected.
Further, FIG. 7 shows a case where the non-feeding end of the second antenna unit 26 is opened in the embodiment, FIG. 8 shows a case where it is short-circuited, and FIG. 9 shows a case where it is terminated.

  From this measurement result, it is understood that the gain is improved by 1 dB or more as compared with the comparative example in any frequency region of at least 920 MHz or less regardless of the state of the non-feeding end of the second antenna unit 26.

[5. effect]
According to this embodiment described in detail above, the following effects are obtained.
(1) In the antenna device 2, the second antenna unit 26 is connected to the second common end To2 to which the terminating resistor 44 is connected in the signal combining circuit 18, and the reception signal of the first antenna unit 12 is signal combined. The first common end To1 of the circuit 18 is supplied to the connection end Tx to which the coaxial cable 30 is connected.

  That is, unlike the conventional device (that is, the comparative example), the received signal from the first antenna unit 12 that is combined by the signal combining circuit 18 can be directly output without passing through the second antenna unit 26. The decrease in the gain of the first antenna unit 12 due to the provision of the antenna unit 26 can be suppressed.

  (2) In the antenna device 2, the strip lines forming the second antenna unit 26 have a meander line structure, and by forming the meander line structure, the distance between the strip lines adjacent to each other is communication. It is set to be shorter than the shortest width of the outer shape of the opening surface of the target antenna. Therefore, it is possible not only to expand the area in which near field communication can be performed on the substrate surface of the dielectric substrate, but also to cope with near field communication with a plurality of types of communication target antennas having different opening surfaces.

  (3) In the antenna device 2, since the second antenna unit 26 is arranged around the first antenna unit 12, it is possible to extend the range in which near field communication can be performed with the communication target antenna. it can.

  (4) In the antenna device 2, the ring-shaped slits 14a and 14b provided in the conductor pattern forming the first antenna unit 12 have a frequency difference between the communication target antennas of the RF tag adjacent to the first antenna unit 12. Since it has the effect of suppressing the above, the first antenna unit 12 can also function as a near-field antenna. That is, the first antenna unit 12 can be made to function as an antenna for both the far field and the near field.

  (5) In the antenna device 2, the two feeding points P included in the first antenna unit 12 and the two combining ends Ti included in the signal combining circuit 18 are connected via the impedance converter 16. Therefore, in the conductor pattern forming the first antenna unit 12, even if the feeding point P cannot be set at a position where the same impedance dance characteristic as the synthesizing end Ti of the signal synthesizing circuit 18 can be obtained, these synthesizing end Ti and the feeding The signal reflection at the point P can be suppressed, and the two can be connected appropriately.

  (6) In the antenna device 2, the hybrid ring forming the signal combining circuit 18 is bent and arranged in an L shape along one corner of the dielectric substrate 10. Therefore, the signal synthesizing circuit 18 can be formed in the empty area on the dielectric substrate 10 around the first antenna unit 12 and the second antenna unit 26. As a result, it is not necessary to expand the substrate area of the dielectric substrate 10 to form the signal synthesizing circuit 18, so that the antenna device 2 can be downsized.

  (7) In the antenna device 2, the shock absorbing material 52 is provided at the corner portion (the connecting portion 22 of the coaxial cable 30) of the dielectric substrate 10 on which the terminating resistor 44 is mounted. Therefore, when the antenna device 2 is used, it is possible to prevent the terminating resistor 44 and the connection portion 22 (especially the soldered portion) of the coaxial cable 30 from being externally impacted and deteriorating the characteristics of the antenna device 2.

  (8) The antenna device 2 is configured as a sheet-shaped planar antenna by forming the conductor pattern forming the first antenna portion 12 and the second antenna portion 26 on the single dielectric substrate 10. .. Therefore, if it is installed on the cash register and used as an antenna device for reading the identification information from the RF tag attached to the product, the identification information can be read from the RF tag without being affected by the position of the RF tag.

[6. Other Embodiments]
Although the embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment, and various modes can be adopted without departing from the scope of the present disclosure.

  (A) In the above embodiment, the number of connection stages of the impedance conversion microstrip line that connects the first antenna unit 12 and the signal synthesis circuit 18 is changed to three, but the number of connection stages is two. Alternatively, it may have four or more stages. The larger the number of connected microstrip lines, the wider the communicable bandwidth.

  (B) In the above embodiment, the ground pattern 28 is provided around the substrate surface 10a of the dielectric substrate 10. However, the ground pattern 28 is provided to prevent the warp of the substrate, and is necessary. It may be omitted depending on

(C) In the above embodiment, the microstrip line forming the second antenna unit 26 is bent in a U shape, but it may be bent in a wavy curved shape.
(D) In the present embodiment, the outer shape of the conductor pattern forming the first antenna unit 12 is a substantially square, but the shape is not limited to this, and for example, other than a circle, a rectangle, an ellipse, or a square. It may be a polygon (for example, a hexagon) or the like. However, it is necessary to form a ring-shaped slit in the conductor pattern in order to enable near-field communication regardless of the shape.

  (E) In the above embodiment, the ring-shaped slits 14a and 14b are formed by combining a plurality of L-shaped slits, but the invention is not limited to this. For example, it may be a combination of linear slits, a combination of curved slits including a free curve, or a combination of slits of any shape in which a straight line and a curved line are combined. May be.

  Note that the plurality of slits formed in the first antenna unit 12 need not necessarily be a ring because the width of the conductor pattern forming the first antenna unit 12 can be made shorter than the shortest width of the outer shape of the communication target antenna. It need not be provided to form. For example, a linear slit, a curved slit including a free curve, or a slit having an arbitrary shape in which a straight line and a curved line are combined may be provided with a space. Further, the slits may be arranged in parallel, or may be arranged with an arbitrary inclination.

  (F) In the above-described embodiment, in order to make the first antenna unit 12 function as a two-point feeding type circularly polarized wave antenna, a hybrid ring formed of a conductor pattern on the dielectric substrate 10 is used. There is. This hybrid ring does not necessarily have to be formed in a conductor pattern on the dielectric substrate 10, and may be configured by using an electronic component such as a monolithic microwave integrated circuit (MMIC).

  (G) In the above embodiment, the signal combining circuit 18 is configured by a hybrid ring, but instead of this, for example, a 90-degree phase shifter and a distributor / mixer may be used. In this case, the 90-degree phase shifter can be composed of a microstrip line formed on the dielectric substrate 10. As the distributor / mixer, for example, a Wilkinson power distributor / combiner or the like can be used.

  (H) In the above embodiment, the antenna device 2 has been described as being used in a cash register, but since the antenna device 2 can perform both far field communication and near field communication, such communication is performed. It can be used anywhere as long as the characteristics are required, not only at the cash register.

  2 ... Antenna device, 10 ... Dielectric substrate, 10a ... Substrate front surface, 10b ... Substrate back surface, 12 ... First antenna part, 13 ... Central pattern removal part, 14a, 14b ... Ring slit, 16 ... Impedance converter, 16a 16c ... Microstrip line, 18 ... Signal combining circuit, 22 ... Connection part, 24 ... Through hole, 26 ... Second antenna part, 28 ... Ground pattern, 30 ... Coaxial cable, 32 ... Center conductor, 34 ... Outer conductor, 42 ... Crimping terminal, 44 ... Termination resistance, 46 ... Eyelet, 50 ... Protective sheet, 52 ... Impact absorbing material, P ... Feed point, Ti ... Composite end, To1 ... First common end, To2 ... Second common end, Tx ... the connection end.

Claims (7)

An antenna device formed by a conductor pattern on a dielectric substrate, comprising:
A first antenna unit having a patch antenna and having two feeding points;
A second antenna section having a single feeding point, which is configured by a strip line;
It is configured by using a hybrid ring having two common ends and two distribution ends, two feeding points of the first antenna unit are connected to the two distribution ends, and one of the two common ends is connected. A first common end and the other as a second common end, the first common end is used as a signal input / output end for the first antenna unit and the second antenna unit, and the second common end is provided with the second common end. A signal combining circuit to which the feeding point of the antenna part and the terminating resistor are connected,
An antenna device provided with. The antenna device according to claim 1, wherein
The stripline forming the second antenna unit has a meander line structure, and the interval between the striplines arranged adjacent to each other by forming the meander line structure is the outer shape of the opening surface of the communication target antenna. An antenna device set to be shorter than the shortest width of. The antenna device according to claim 1 or 2, wherein
The second antenna unit has a structure in which a non-feed end of the strip line is opened. The antenna device according to any one of claims 1 to 3, wherein:
In the dielectric substrate, a conductor pattern that forms a patch antenna that serves as a radiator of the first antenna unit is formed on a substrate surface that is one of the substrate surfaces, and a ground surface is formed on the back surface of the substrate that is the other substrate surface. Conductor pattern is formed,
The conductor pattern forming the patch antenna is provided with a plurality of slits,
The plurality of slits are arranged such that the width of the first antenna section divided by the slits is shorter than the shortest width of the outer shape of the opening surface of the communication target antenna. The antenna device according to any one of claims 1 to 4, wherein:
An impedance converter including a microstrip line that connects the two feeding points of the first antenna unit and the two combining ends of the signal combining circuit is further provided.
Antenna device. The antenna device according to any one of claims 1 to 5, wherein:
The second antenna unit is an antenna device arranged around the first antenna unit. The antenna device according to any one of claims 1 to 6, wherein:
The antenna device, wherein the hybrid ring forming the signal combining circuit is bent and arranged in an L shape along one corner of the dielectric substrate.