JP7470854B1 - Wireless communication devices - Google Patents

Abstract

[Problem] To provide a wireless communication device that can extend the communication distance and improve the wireless communication function compared to the conventional devices. [Solution] A wireless communication device 10 of a non-power-feed type equipped with a radiating means 11 that functions as a radiator, the radiating means 11 having first and second radiating sections 15, 16 arranged in parallel, each having a metallic round bar 17, 18 that is insulated by aligning the axes of the radiating sections to form a gap 19 or by arranging an insulating material, the first radiating section 15 has the round bar 17 and the round bar 18 connected via an IC element 20 that records unique information, and the round bar 18 of the first radiating section 15 and the round bar 18 of the second radiating section 16, and the round bar 18 of the first radiating section 15 and the round bar 17 of the second radiating section 16 are cross-connected via conductors 22, 23. [Selected Figure] Figure 1

Description

The present invention relates to a wireless communication device equipped with a radiator.

In manufacturing plants, etc., RF tags are sometimes used to identify and manage products, etc. By attaching RF tags with embedded unique information to products, etc. and having a reader/writer exchange information with the RF tags via wireless communication, it is possible to realize logistics management and location management of products, etc.
There are two types of RF tags: active, which are powered by a built-in battery, and passive, which do not have a battery and are powered by radio waves received from outside. Active RF tags can achieve long communication distances, but are expensive and require the remaining capacity of the built-in battery to be known. Passive RF tags, on the other hand, are cheaper and do not require the remaining battery capacity to be known, but generally have a communication distance of about 5 to 6 meters, and depending on the application, it is required to extend the communication distance.
Therefore, the present inventors have proposed a wireless communication device that uses a commercially available passive RF tag (sticker type or mold type) as a radiator (see Patent Document 1).

JP 2019-16855 A

Although the above wireless communication devices have been able to extend communication distances and improve wireless communication functions, further improvements in performance have been desired.
An object of the present invention is to provide a wireless communication device that can extend the communication distance and improve the wireless communication function more than ever before.

The present inventors have come to the following findings while attempting to improve the performance of the above-mentioned wireless communication device.
Even if a wireless communication device incorporates a reflector and director, its performance depends on the performance of the selected RF tag.
- The length and spacing of the reflector and director must be adjusted depending on the type of RF tag selected, which places a burden on design and production.
- The RF tags used are commercially available packaged products and cannot be modified to improve performance.
-If mass production is required, it is advisable to narrow it down to a specific RF tag.
In order to further improve the performance of wireless communication devices, the inventors conducted various studies on the configuration of radiators based on the above-mentioned findings and arrived at the present invention.

That is, the present invention is as follows.
[1] A wireless communication device of a non-powered wire type having a radiating means functioning as a radiator,
The radiation means comprises:
The antenna has first and second radiating sections arranged in parallel, each having a metal round rod A and a metal round rod B that are insulated by aligning their axes and forming a gap therebetween or by placing an insulating material therebetween,
The first radiating portion is configured such that the round bar A and the round bar B are connected via an IC element having unique information recorded thereon,
A wireless communication device, characterized in that the round bar A of the first radiating section and the round bar B of the second radiating section, and the round bar B of the first radiating section and the round bar A of the second radiating section are connected in a cross-connected manner via a conductor.

[2] The second radiating portion is arranged in parallel to two or more of the first radiating portions on one side of the first radiating portion,
The wireless communication device according to the above-mentioned [1], characterized in that the round bar A of one of the second radiating parts and the round bar B of the other of the second radiating parts, which are adjacent to each other, and the round bar B of one of the second radiating parts and the round bar A of the other of the second radiating parts are connected in a cross-connected manner via conductors.

[3] For the round bars A and B of the radiation means,
A metal round bar C that functions as a reflector and is arranged parallel to one side of the bar;
A metal round rod D that functions as a director and is arranged parallel to the other side.
The wireless communication device according to [1] or [2] above, further comprising:
[4] The wireless communication device according to the above [3], wherein the round rods D are arranged in parallel to each other.
[5] The wireless communication device according to the above [3] or [4], characterized in that the round bars A to D are immovably attached and fixed to supports that support the round bars A to D, respectively.

The wireless communication device of the present invention can extend the communication distance and improve the wireless communication function compared to conventional devices.

1A and 1B are a plan view and a side view, respectively, of a wireless communication device according to an embodiment of the present invention. 4A and 4B are respectively a partially enlarged plan view and a partially enlarged side view of a first radiating portion of the radiating means of the wireless communication device. FIG. 13 is a plan view of a radiating means of a wireless communication device according to a modified example. 1A to 1C are explanatory diagrams of a wireless communication function using a wireless communication device according to an embodiment of the present invention. 11 is an explanatory diagram showing an example in which first radiating portions of the radiating means of the wireless communication device are arranged to cross each other; FIG. 13A and 13B are graphs showing an image of in-phase synthesis of radiating means of a wireless communication device according to an embodiment.

Next, with reference to the attached drawings, an embodiment of the present invention will be described for understanding the present invention.
As shown in Figures 1(a), (b), 2(a) and (b), a wireless communication device 10 according to an embodiment of the present invention is a parasitic-wire type device equipped with a radiation means 11 functioning as a radiator, a reflector 12 and a director 13, and can be widely used for logistics management and location management of products, etc. The radiation means 11, the reflector 12 and the director 13 are attached to a support 14 such that the reflector 12 and the director 13 are disposed on both sides of the radiation means 11, respectively, and since directivity is obtained in the direction of the director 13 as seen from the radiation means 11, the directivity direction D (see the arrow in Figures 1(a) and (b)) is set as the forward direction, and will be described in detail below.

The wireless communication device 10 being of the unpowered type means that the device is not provided with a power supply line and is of the passive type that is driven by radio waves received from the outside as an energy source.
As shown in Figures 1(a) and (b), the radiating means 11, reflector 12, and director 13 of the wireless communication device 10 are attached and fixed to a support 14 made of a metal or plastic rectangular columnar material (rod material) with their axes aligned in a direction perpendicular to the longitudinal direction of the support 14 when viewed in a plane. However, the material and shape (cross-sectional shape) of the support 14 are not particularly limited as long as the radiating means 11, reflector 12, and director 13 can be attached and fixed and the wireless communication device 10 can function.

The radiating means 11 has first and second radiating parts 15, 16 arranged in parallel, and each of the first and second radiating parts 15, 16 has two round bars (an example of round bar A) 17 and a round bar (an example of round bar B) 18 (basically a dipole antenna configuration). In this way, by configuring the first and second radiating parts 15, 16 of the radiating means 11 with the round bars 17, 18, respectively, electrical advantages are obtained compared to other shapes.
The round bars 17, 18 are cylindrical bars (solid, not hollow (pipes)) with a circular cross section, and are made of metal such as aluminum alloy or stainless steel, but considering ease of transport (lightweight), it is preferable to configure them from an aluminum alloy. The diameter of the round bars 17, 18 is, for example, about 3 mm to 10 mm, and the larger the diameter, the easier it is to obtain a skin effect (the easier it is for electric current to flow), but considering ease of transport, it is preferable that the diameter be about 3 mm to 7 mm.
The cross-sectional shape of the round bars 17 and 18 is a perfect circle, but may be an ellipse or the like.

The round bars 17 and 18 are arranged with their axes aligned (on the same axis) and insulated from each other.
Here, "aligning the axes" does not only mean that the axes of the round bars 17 and 18 are perfectly aligned, but also includes the case where they are slightly misaligned as long as their function as a radiator is not impaired.
The insulating state can be achieved by forming a gap 19 (air layer) between the round bars 17 and 18, but it is preferable from the viewpoint of manufacturing to achieve this by disposing an insulating material. Note that, as the insulating material, for example, plastic sheet material, paper, hardened resin (liquid resin filled in the gap and hardened), etc. can be used, but there is no particular limitation as long as the insulating state can be achieved.
The distance between the end faces of the round bars 17 and 18 that face each other with their axes aligned, i.e., the interval d of the gap 19, is preferably 3 mm or less, more preferably 1 mm or less, even more preferably 500 μm or less, and particularly preferably 300 μm or less. On the other hand, the lower limit is more than 0 μm, but in reality it is sufficient to set it to about 100 μm.
When the above insulating material is used, the thickness of the insulating material may be adjusted to the above dimensions.

The round bars 17 and 18 constituting the first radiating section 15 are electrically connected via an IC element (IC chip, semiconductor) 20, as shown in Figures 1(a) and 1(b) and Figures 2(a) and 2(b).
The IC element 20 has a well-known structure based on silicon (Si), in which an identification code, which is unique information, is recorded (encoded), and the stored identification code is wirelessly transmitted to the outside by electromotive force obtained by receiving radio waves from an antenna.
The IC element 20 can be used by cutting out a region including the IC element 20 from a commercially available RF tag (seal tag, inlay), but it can also be used by recording unique information on a commercially available IC element. The IC element 20 is preferably cut out from the commercially available RF tag so as to remove the antenna portion together with the wiring (not shown) formed on the sheet-like substrate 21 (integrated (patterned) with the sheet-like substrate 21).

The connection of the IC element 20 to the round bars 17, 18 is implemented using wiring formed on the sheet-like substrate 21, but can also be implemented using a conductor (such as a copper wire) separately connected to the IC element.
The attachment position of this wiring or conductor (hereinafter also referred to as wiring, etc.) on round bars 17, 18 can be within a range of up to 10 mm from the opposing end faces of round bars 17, 18, for example, the end faces, since the closer it is to the opposing end faces of round bars 17, 18, the better the performance as a radiator. However, a range of up to 5 mm is preferable, a range of up to 2 mm is even more preferable, and a range of up to 1 mm is particularly preferable.
The method of attaching wiring etc. to the round bar is not particularly limited as long as the wiring etc. does not come off the round bar. For example, it can be done using sticky tape or resin (adhesive), but it can also be done by forming a small hole in the end of the round bar and screwing it in place.

The round bars 17, 18 of the first radiating section 15 and the round bars 17, 18 of the second radiating section 16, which are arranged in parallel, are connected crosswise (in a cross-connected state) via conductors (copper wires (wiring) or the like) 22, 23. Specifically, the round bar 17 on the upper side (one side) of the first radiating section 15 in Fig. 1 and the round bar 18 on the lower side (the other side) of the second radiating section 16 in Fig. 1 are electrically connected by the conductor 22, and the round bar 18 on the lower side of the first radiating section 15 in Fig. 1 and the round bar 17 on the upper side of the second radiating section 16 in Fig. 1 are electrically connected by the conductor 23.
The mounting position of the conductor on the round bars 17, 18 should be within a range of up to 10 mm from the opposing end faces of the round bars 17, 18, since the closer it is to the opposing end faces of the round bars 17, 18, the better the performance of the radiator. However, a range of up to 5 mm is preferable, a range of up to 2 mm is even more preferable, and a range of up to 1 mm is particularly preferable.
This improves the performance of the radiator compared to when only the first radiating portion 15 is used.

As shown in Fig. 3, it is preferable that two second radiating portions 16 are arranged in parallel behind (on one side of) the first radiating portion 15. The number of second radiating portions may be three or more, and the upper limit of the number is not particularly limited, but is practically about 10, and preferably about 5.
Here, when two or more second radiating portions 16 are arranged, the round bars 17 and 18 of the second radiating portion 16 on the left side (one side) of Fig. 3 and the round bars 17 and 18 of the second radiating portion 16 on the right side (other side) of Fig. 3, which are arranged in parallel, are connected crosswise (in a cross-connected state) via conductors (copper wires (wiring) etc.) 24 and 25. Specifically, the round bar 17 on the upper side (one side) of Fig. 3 of the second radiating portion 16 on the left side of Fig. 3 and the round bar 18 on the lower side (other side) of Fig. 3 of the second radiating portion 16 on the right side of Fig. 3 are electrically connected by the conductor 24, and the round bar 18 on the lower side of Fig. 3 of the second radiating portion 16 on the left side of Fig. 3 and the round bar 17 on the upper side of Fig. 3 of the second radiating portion 16 on the right side of Fig. 3 are electrically connected by the conductor 25.
The above configuration constitutes the radiating means 11a.
As a result, the radiating means 11a can further improve the performance as a radiator compared to the radiating means 11 (see FIG. 1) that uses the first radiating portion 15 and one second radiating portion 16.

The round bars 17, 18 of the first and second radiating sections 15, 16 described above can be attached and fixed to the support 14 by placing the opposing sides of the round bars 17 and 18 on a holding means 26, specifically, a support base 27 attached and fixed to the upper surface of the support 14, and screwing the round bars 17, 18 onto the support base 27 (not shown); however, there is no particular limitation as long as the round bars 17, 18 can be attached and fixed to the support 14.
The radiating means 11 on the support base 27 is exposed to the outside, but is preferably covered with a cover material or the like, including the IC element 20 and the wiring 22, 23. The first radiating section 15 may be integrated by coating the round bars 17, 18, the IC element 20, the wiring, and the conductors 22, 23 with resin or the like, and the second radiating section 16 may be integrated by coating the round bars 17, 18 and the conductors 22, 23 with resin or the like (the same applies to the conductors 24, 25 shown in FIG. 3).

As shown in Figures 1(a) and (b) , a metallic round bar (an example of round bar C) 28 functioning as a reflector 12 is arranged behind (on one side) the radiating means 11 in parallel to the round bars 17 and 18 of the second radiating section 16 of the radiating means 11.
The round bar 28 has the same configuration as the round bars 17 and 18, that is, it is a cylindrical bar with a circular cross section (perfect circle or ellipse, etc.) and is made of a metal such as an aluminum alloy or stainless steel, but is preferably made of an aluminum alloy. The diameter of this round bar 28 is, for example, about 3 mm to 10 mm, but is preferably about 4 mm to 7 mm.
The round bar 28 can be attached and fixed to the support 14 by passing it through a holding means 29, specifically, a support base 30 attached and fixed to the upper surface of the support 14, and screwing it in place; however, as long as the round bar 28 can be attached and fixed to the support 14, there is no particular limitation.

1(a) and 1(b), on the opposite side of the radiating means 11 from the reflector 12, i.e., on the front (other side) of the radiating means 11, two metallic round bars (an example of round bar D) 31 functioning as directors 13 are arranged parallel to the round bars 17 and 18 of the first radiating section 15 of the radiating means 11. The number of round bars may be one or more than two, but the practical upper limit is about ten. By providing a plurality of directors 13 in this way, the communication distance can be further extended.
The round bar 31 has the same configuration as the round bars 17, 18, and 28, that is, a cylindrical bar with a circular cross section (perfect circle or ellipse, etc.) and is made of a metal such as an aluminum alloy or stainless steel, but is preferably made of an aluminum alloy. The diameter of this round bar 31 is, for example, about 3 mm to 10 mm, but is preferably about 4 mm to 7 mm.
The round bar 31 can be attached and fixed to the support 14 by passing it through the holding means 32, specifically, the support base 33 attached and fixed to the upper surface of the support 14, and screwing it in place; however, there is no particular limitation as long as the round bar 31 can be attached and fixed to the support 14.

As shown in Fig. 1(a), the lengths of the first and second radiating sections 15, 16 (round bars 17, 18), the reflector 12 (round bar 22), and the director 13 (round bar 25) of the above-mentioned radiating means 11 are set such that, based on the length L1 of the first and second radiating sections 15, 16, the length L2 of the reflector 12 is slightly longer and the length L3 of the director 13 is slightly shorter. Note that the length L1 of the first radiating section 15 and the second radiating section 16 is the same.
Specifically, since the frequency of the radio wave used for the IC element 18 in which the unique information is recorded is 920 MHz, the wavelength λ is 32.6 cm, and therefore the length L1 of the first and second radiating portions 15, 16 is 163.0 mm (=λ/2). The lengths of the round bars 17 and 18 constituting the first and second radiating portions 15, 16 are the same, 81.5 mm (=λ/4).
Using the length L1 of the first and second radiating sections 15 and 16 as a reference, the length L2 of the reflector 12 and the length L3 of the director 13 are adjusted while checking the operation. For example, the length L2 is made several mm (5 mm or less) longer than the length L1, and the length L3 is made several mm (5 mm or less) shorter than the length L1. When multiple round bars functioning as directors 13 are arranged, the lengths of each are shortened, for example, little by little (several mm (5 mm or less) at a time) toward the front (direction away from the radiating means 11).
Furthermore, the interval S1 between adjacent radiating means 11 (second radiating portion 16) and reflector 12, the interval S2 between radiating means 11 (first radiating portion 15) and director 13, and the interval S3 between directors 13 are also adjusted while checking the operation. Note that the interval S between the first radiating portion 15 and the second radiating portion 16 is about λ/8. Also, when two or more second radiating portions 16 are arranged, the interval between adjacent second radiating portions 16 is about λ/8.

The wireless communication device 10 of the present invention described above has a structure without a power supply line, and the whole including the reflector 12 and the director 13 functions as a passive RF tag.
In this way, since a power supply line is not required, the lengths of the first and second radiating sections 15, 16 can be set to their theoretical lengths, and therefore design work such as wavelength shortening can be omitted (the design can be simplified and simplified). This allows for efficient manufacturing, improved performance, and stabilized quality.
Therefore, in the wireless communication device 10 of the present invention, the radiating means 11, reflector 12, and director 13 can be attached and fixed to the support 14 so that they cannot move, so there is no need to configure the reflector and director to be slidable in the longitudinal direction of the support, as described in the above-mentioned Patent Document 1.

Next, the wireless communication function of the wireless communication device 10 to which the present invention is applied will be described with reference to Figures 4(a) to 4(c). Note that each component will be described with the same reference numerals as those in the wireless communication device 10 of the above embodiment.
First, the wireless communication device 10 is capable of adapting to the inclination of the wireless communication device 10 and the antenna 50. This point will be described below.

When the polarization characteristics of the radiation means 11 are horizontally polarized, as shown in Figure 4 (a), in a wireless communication device 10 having a reflector 12 and a director 13 extending horizontally, the IC element 20 (unique information) can be reliably detected if the polarization direction is aligned with the antenna 50.
4B, when the wireless communication device 10 and the antenna 50 are tilted relative to each other in a rotational direction about the axis of the directional direction D, the polarization direction between the wireless communication device 10 and the antenna 50 shifts, and the communication distance gradually decreases. In this way, depending on the relative tilt between the wireless communication device 10 and the antenna 50, there is a risk that the IC element 20 will not be detected.

Therefore, as shown in Figure 4 (c), the radiating means 11 (first and second radiating sections 15, 16), reflector 12, and director 13 are arranged so that they cross each other, that is, the radiating means 11, reflector 12, and director 13 are arranged so that they extend in four directions perpendicular to the directivity direction D. Note that even when arranged so that they cross, the radiating means 11, reflector 12, and director 13 are arranged parallel to each other. In other words, the radiating means 11, reflector 12, and director 13 are considered as one set, and a configuration having two sets of these forms a wireless communication device.
By forming a cross antenna in this manner, even if the wireless communication device 10 and the antenna 50 are tilted relative to each other in a rotational direction around the directional direction D (for example, even if the antenna 50 is tilted as shown in Figure 4 (c)), i.e., even if the polarization direction is misaligned between the wireless communication device 10 and the antenna 50, the IC element 20 can be reliably detected.

FIG. 5 shows a configuration example in which the radiating means 11 (first and second radiating portions 15 and 16), the reflector 12, and the director 13 are arranged to cross each other.
The first radiating section 15 (round bars 17, 18) is disposed so as to penetrate the left and right side surfaces of the support 60, and the first radiating section 15 (round bars 17, 18) is disposed so as to penetrate the top and bottom surfaces of the support 60 (the same applies to the round bars 17, 18 of the second radiating section 16, the round bar 28 of the reflector 12, and the round bar 31 of the director 13). It is preferable that the crossing positions are the same in the directional direction D, but as shown in Figure 5, there may be some deviation in the directional direction D as long as they are considered to be approximately the same positions. This is because there is no effect on the communication distance if the mutual intervals between the radiating means 11, the reflector 12, and the director 13 do not change.

The above-mentioned configuration can handle circularly polarized waves, which is difficult with a two-dimensional structure, and can accommodate the inclination of the wireless communication device 10 and the antenna 50. In other words, if the wireless communication device 10 and the antenna 50 are used in an environment where the inclination changes, a cross antenna can be used as described in FIG. 4(c).

Next, an example of how the wireless communication device 10 is used will be described.
First, the wireless communication device 10 is placed on the object to be tracked.
In addition, a reader is installed at a location different from the target object. For the antenna of this reader, for example, a Yagi-Uda antenna is used to give it directionality. The wireless communication device 10 and the antenna are installed at height positions that enable mutual communication (see FIG. 4(a)).
In such an example of use, the reader can identify the wireless communication device 10 by exchanging information with the IC element 20 of the wireless communication device 10 via wireless communication.
It is also possible to estimate the distance between the reader and the wireless communication device 10 based on the strength of the radio waves transmitted between them via wireless communication.

Next, examples carried out to confirm the effects of the present invention will be described.
Here, an antenna (reader) consisting of three elements (one radiator, one reflector, and one director) and equipped with a feeder line (connection cable: 15 m) was used, and the electric field strength was measured at a communication distance of 1 m.
The measurement targets used three types of radiating means functioning as a radiator: 1) a radiating means consisting of only a first radiating portion, 2) a radiating means consisting of a first radiating portion (Ra1) and one second radiating portion (Ra2) (see Figure 1), and 3) a radiating means consisting of a first radiating portion (Ra1) and two second radiating portions (Ra2, Ra3) (see Figure 3).
As a result, in the case of 1) above, a received radio wave intensity of -45 dBm to -48 dBm was obtained. It was confirmed that the wireless communication device composed of this first radiator, a reflector, and a director can extend the communication distance and improve the wireless communication function compared to a wireless communication device that uses a conventional commercially available RF tag without modification (Patent Document 1).

In the case of 2) above, a received radio wave strength of -39 dBm to -40 dBm was obtained, which was about 7 dBm higher than in the case of 1) above.
In the case of 2) above, as can be seen from the image of in-phase synthesis shown in Figure 6 (a), when the IC element of the first radiating section (Ra1) is excited, a radio wave that is in the opposite phase to the radio wave radiated from the first radiating section (Ra1) is radiated.
As a result, between the first radiating section (Ra1) and the second radiating section (Ra2), an in-phase synthesis of the first radiating section (Ra1) and one in-phase synthesis of the second radiating section (Ra2) are formed, and the two are further synthesized.
Therefore, it can be estimated that the radio wave intensity between the radiating means having the first and second radiating portions (Ra1, Ra2) and the director will be 4 to 8 times that of a single normal radiator.

Furthermore, in the case of 3) above, as can be inferred from the image of in-phase synthesis shown in Figure 6(b), a received radio wave strength of -32 dBm to -33 dBm was obtained, which is an increase of approximately 7 dBm from the case of 2) above.

From the above, it has been confirmed that by using the wireless communication device of the present invention, it is possible to extend the communication distance and improve the wireless communication function compared to conventional methods.

Although the present invention has been described above with reference to one embodiment, the present invention is not limited to the configuration described in the above embodiment, and includes other embodiments and modifications that are possible within the scope of the claims. For example, the wireless communication device of the present invention may be configured by combining some or all of the above-mentioned embodiments and modifications, which are also included in the scope of the present invention.
In the above embodiment, the wireless communication device has been described as having a radiating means, a reflector, and a director, but in theory it may also be configured to have only a radiating means (reflector and director are not required), or a radiating means and a reflector (director is not required), or even a radiating means and a director (reflector is not required).

The present invention is industrially useful because it can provide wireless communication equipment that can extend communication distances and improve wireless communication functions compared to conventional equipment.

10: wireless communication device, 11, 11a: radiation means, 12: reflector, 13: director, 14: support, 15: first radiation section, 16: second radiation section, 17: round bar (round bar A), 18: round bar (round bar B), 19: gap, 20: IC element, 21: sheet-like substrate, 22-25: conductor, 26: holding means, 27: support base, 28: round bar (round bar C), 29: holding means, 30: support base, 31: round bar (round bar D), 32: holding means, 33: support base, 50: antenna, 60: support

Claims (5)

A wireless communication device of a non-powered wire type having a radiating means functioning as a radiator,
The radiation means comprises:
The antenna has first and second radiating sections arranged in parallel, each having a metal round rod A and a metal round rod B that are insulated by aligning their axes and forming a gap therebetween or by placing an insulating material therebetween,
The first radiation portion is configured such that the round bar A and the round bar B are connected via a sheet-like wiring substrate having an IC element having unique information recorded thereon ,
A wireless communication device, characterized in that the round bar A of the first radiating section and the round bar B of the second radiating section, and the round bar B of the first radiating section and the round bar A of the second radiating section are connected in a cross-connected manner via a conductor. Two or more of the second radiating portions are arranged in parallel on one side of the first radiating portion,
2. The wireless communication device according to claim 1, characterized in that the round bar A of one of the second radiating parts and the round bar B of the other of the second radiating parts, which are adjacent to each other, and the round bar B of one of the second radiating parts and the round bar A of the other of the second radiating parts are connected in a cross-connected manner via conductors. For the round bars A and B of the radiation means,
A metal round bar C that functions as a reflector and is arranged parallel to one side of the bar;
A metal round rod D that functions as a director and is arranged parallel to the other side.
3. The wireless communication device according to claim 1, further comprising: The wireless communication device according to claim 3, characterized in that the round rods D are arranged in parallel. 5. The wireless communication device according to claim 4, wherein the round bars A to D are immovably attached and fixed to a support body that supports the round bars A to D, respectively.

Images