Dielectric rod antenna and dielectric rod

Abstract

The purpose of the present invention is to provide a dielectric rod antenna and a dielectric rod which are capable of relatively reducing transmission line loss and increasing gain in an array antenna having a millimeter band or more, and which are capable of coping with beam scanning. A dielectric rod is attached to an external antenna, and includes a plurality of dielectric elements. The dielectric elements are arranged such that one or more dielectric elements correspond to each of the antenna elements of the external antenna. The dielectric element has a base portion, a tip portion, and a main body portion connecting the base portion and the tip portion. The base portion is arranged in a lattice shape. The main body portion has a shape extending substantially linearly from the base portion toward the tip portion. The main body portions are disposed so as to be separated from each other from the base portion toward the tip portion.

Description

Technical Field

[0001] The present invention relates to a dielectric rod antenna and a dielectric rod, and in particular to a dielectric rod antenna and a dielectric rod used in a mobile communication system and a base station antenna system. Background Art

[0002] In the 5G millimeter wave band, the area is secured by scanning a high-gain beam based on an array antenna. In Beyond 5G / 6G, the use of high frequencies up to 300 GHz is being studied, and the need for high-gain beam scanning is increasing. In addition, as a gain enhancement technology different from the array antenna, there is a dielectric rod antenna that extends the dielectric in the axial direction.

[0003] The millimeter wave band (28 GHz band) is allocated from 5G. However, as a disadvantage, the loss caused by the communication distance is large.

[0004] Scanning high-gain beams based on array antennas enables connections between each terminal and the base station. Regarding this tendency, the higher the frequency, the greater the problem.

[0005] An array antenna is generally composed of more than 64 elements in an 8×8 arrangement, i.e. 8 rows and 8 columns, and the maximum antenna gain is usually more than 22dBi.

[0006] The transmission line on the back side is very long, so a large loss such as a loss of more than 4 dB is generated. Therefore, reducing the transmission line loss has become a problem. In 6G, which is expected to be used up to 300 GHz, there is a concern that the transmission line loss will increase further.

[0007] A beamforming device and a beamforming method are described in Patent Document 1. An amplifier and a phase shifter are arranged in each element to realize beam scanning.

[0008] A mixer is connected to each element, and a longer transmission line is designed at an intermediate frequency, that is, a frequency lower than the frequency of actual wireless communication, thereby reducing the loss.

[0009] A dielectric rod antenna is described in Patent Document 2. In this dielectric rod antenna, the antenna gain is enhanced by extending the dielectric in the direction in which radio waves propagate.

[0010] Non-Patent Document 1 describes a dielectric rod antenna array in which a dielectric rod is provided for each antenna element.

[0011] Prior art literature

[0012] Patent Literature

[0013] Patent Document 1: Japanese Patent Application Publication No. 2021-16077

[0014] Patent Document 2: Japanese Patent Application Publication No. 2005-347936

[0015] Non-patent literature 1: Gabriel L. Safold et al., “Dielectric Rod Antenna Array With Planar Folded Slot Antenna Excitation” IEEE Open Journal of Antennas and Propagation, Volume 2, 2021, pp. 664-673 Summary of the invention

[0016] Problems to be solved by the invention

[0017] The large-scale, multiple mixing circuits described in Patent Document 1 will lead to increased costs and complex wiring design. In the structure described in Patent Document 2, although the transmission line loss does not increase, beam scanning cannot be achieved. In the dielectric rod antenna array described in Non-Patent Document 1, each rod faces the same direction. Although it can achieve an increase in antenna gain, it cannot cope with beam scanning for forming a wide-angle area. In addition, the dielectric needs to be grounded and adjusted separately, which not only increases the cost of manufacturing and assembly, but also requires the antenna elements to be readjusted one by one on site due to deviations caused by the impact during transportation, making it unrealistic for practical use.

[0018] Therefore, an object of the present invention is to realize a low-cost dielectric rod antenna and a dielectric rod that can achieve a relative reduction in transmission line loss and high gain in an array antenna above the millimeter wave band and can cope with beam scanning.

[0019] Other objects of the present invention will also be described in the embodiments for carrying out the invention.

[0020] Solutions to Solve Problems

[0021] A dielectric rod according to an embodiment of the present invention is a dielectric rod installed in an external antenna, and is characterized in that:

[0022] Having a plurality of dielectric elements,

[0023] The plurality of dielectric elements are arranged in such a manner that at least one of the dielectric elements corresponds to each antenna element of the external antenna.

[0024] The dielectric element comprises a base portion, a front end portion, and a main body portion connecting the base portion and the front end portion.

[0025] The base is configured in a grid pattern.

[0026] The main body has a shape extending substantially linearly from the base toward the front end.

[0027] The main body parts are arranged to be separated from each other from the base part toward the front end part.

[0028] A dielectric rod according to an embodiment of the present invention is any one of the above dielectric rods, characterized in that the grid is in one row.

[0029] A dielectric rod according to an embodiment of the present invention is any one of the above dielectric rods, characterized in that the lattice has m rows and n columns, and m and n are natural numbers greater than or equal to 2.

[0030] A dielectric rod according to an embodiment of the present invention is any of the above-mentioned dielectric rods, wherein all of the main body portions are arranged to be separated from each other from the base portion toward the tip portion in at least one direction.

[0031] A dielectric rod according to an embodiment of the present invention is any of the above-mentioned dielectric rods, wherein the main bodies are arranged to be separated from each other from the base toward the tip.

[0032] A dielectric rod according to an embodiment of the present invention is any one of the above-mentioned dielectric rods, characterized in that a dielectric constant is 4 or less, and a length of the dielectric element is 15 wavelengths or more.

[0033] A dielectric rod according to an embodiment of the present invention is any one of the above dielectric rods, characterized in that the dielectric rod is transparent.

[0034] A dielectric rod according to an embodiment of the present invention is any one of the above-mentioned dielectric rods, characterized in having a fixing portion for fixing a positional relationship with an antenna.

[0035] A dielectric rod according to an embodiment of the present invention is any of the above dielectric rods, wherein the main body has a shape that tapers from the base toward the front end, and the reduction rate of the diameter of the dielectric element relative to the length direction of the dielectric element increases toward the base.

[0036] A dielectric rod according to an embodiment of the present invention is any one of the above-mentioned dielectric rods, wherein the main body is in a smooth curved shape.

[0037] A dielectric rod according to an embodiment of the present invention is any of the above-mentioned dielectric rods, wherein the thickness of the main body portion changes in stages and becomes longer toward the front end in each stage.

[0038] A dielectric rod antenna according to an embodiment of the present invention is a dielectric rod antenna characterized by comprising the dielectric rod according to any one of claims 1 to 7 and an antenna unit having a plurality of antenna elements.

[0039] A dielectric rod antenna in an embodiment of the present invention is any one of the above-mentioned dielectric rod antennas, characterized in that it includes a transmitting unit that transmits radio waves of millimeter waves or higher, or a receiving unit that receives radio waves of millimeter waves or higher.

[0040] Effects of the Invention

[0041] Through the above structure, the present invention realizes a new dielectric rod antenna and dielectric rod, which, compared with the past: first, reduces the loss; second, can achieve at least the same antenna gain, that is, typically a maximum of more than 22dBi; third, can achieve at least the same beam scanning as the equivalent antenna.

[0042] Other effects of the present invention will also be described in the embodiments for carrying out the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A configuration example of a dielectric rod antenna according to an embodiment of the present invention is shown.

[0044] Figure 2 A configuration example of a dielectric rod antenna according to an embodiment of the present invention is shown.

[0045] Figure 3 The results of the dielectric rod antenna according to one embodiment of the present invention are shown.

[0046] Figure 4 The results of the comparative example are shown.

[0047] Figure 5 A configuration example of a dielectric rod antenna according to an embodiment of the present invention is shown.

[0048] Figure 6 A configuration example of a dielectric rod antenna according to an embodiment of the present invention is shown.

[0049] Figure 7 A configuration example of a dielectric rod antenna according to an embodiment of the present invention is shown.

[0050] Figure 8 A configuration example of a dielectric rod antenna according to an embodiment of the present invention is shown.

[0051] Fig. 9 A configuration example of a dielectric rod antenna according to an embodiment of the present invention is shown.

[0052] Fig.10 A configuration example of a dielectric rod antenna according to an embodiment of the present invention is shown.

[0053] Fig.11 A configuration example of a dielectric rod antenna according to an embodiment of the present invention is shown.

[0054] Fig.12A configuration example of a dielectric rod antenna according to an embodiment of the present invention is shown.

[0055] Fig.13 A configuration example of a dielectric rod antenna according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0056] Figure 1 An example of a dielectric rod 100 according to an embodiment of the present invention is shown.

[0057] The dielectric rod 100 is installed on Figure 2 An external antenna 400 is shown.

[0058] An array antenna is used as an excitation source, and a dielectric designed to increase the gain in multiple beam directions achieved by a beam forming or multi-beam circuit is provided.

[0059] If the number of excitation source elements matches the number of beams used (the number of directions in which the rods extend), each beam can be designed to be separable. The excitation source beamforming method can be handled by any of analog / digital beamforming, multi-beam using Butler matrix, etc.

[0060] The dielectric rod 100 of this embodiment includes a plurality of dielectric elements 110. The dielectric elements 110 are arranged so that one or more dielectric elements 110 correspond to each antenna element 410 of the external antenna 400. In this embodiment, one or more dielectric elements 110 are arranged so as to face each antenna element 410.

[0061] The dielectric element 110 includes a base portion 111 , a front end portion 112 , and a main body portion 113 connecting the base portion 111 and the front end portion 112 .

[0062] The base 111 is arranged in a grid shape. "Arranged in a grid shape" means that the positional relationship between each other is fixed and the base is arranged without gaps. The grid can be two-dimensional, or it can be a horizontal row. Of course, it can be arranged in various directions such as inclined or vertical according to the setting method of the antenna. It should be noted that in this description, the dielectric rod antenna is sometimes referred to as an antenna.

[0063] The main body portion 113 has a shape extending substantially linearly from the base portion 111 toward the front end portion 112 .

[0064] The main bodies 113 are arranged so as to be separated from each other from the base 111 toward the front end 112. Here, "the main bodies 113 are arranged so as to be separated from each other from the base 111 toward the front end 112" also includes the case where the distances between them are the same. That is, the distances of the main bodies 113 are configured to be the same or different. However, it does not include the case where all the distances are the same. That is, at least a part of the main bodies are separated from each other by their distances, and as a whole, are arranged to be separated from each other from the base 111 toward the front end 112. According to this structure, efficient communication can be achieved over a wide range.

[0065] In one embodiment, if Figure 1 As shown, it can also be configured so that in at least one direction such as the horizontal direction and the vertical direction, all the main bodies 113 are arranged in a manner separated from each other from the base 111 toward the front end 112. According to this structure, it is possible to achieve efficient communication in a wider range in accordance with the direction in which the range of objects to be sent and received is expanded.

[0066] like Figure 1 As shown, the dielectric can be extended in the beam direction used. Therefore, while achieving high gain, the transmission line loss can be minimized by making the dielectric rod 100 out of a low-loss material.

[0067] replace Figure 2 The external antenna 400, such as Figure 6 As shown, the excitation source may be an array antenna 300 capable of performing beam scanning in the horizontal / vertical directions.

[0068] like Figure 1 As shown, the number of antenna elements is the same as the number of beams used. In this embodiment, the beams are converged into 4 beams. In particular, it can help to achieve the following beam scanning. That is, first, the maximum direction of each beam can be separated. And, second, the overlap of each beam can be designed at an appropriate level.

[0069] In the technology described in Patent Document 1, the antenna gain is ensured by increasing the number of elements, but in this embodiment, the gain can be increased without increasing the number of elements by using the dielectric rod 100. Furthermore, the transmission line loss can also be reduced at the same time. In addition, the dielectric rod 100 of the present invention can achieve high gain for beams in different directions.

[0070] In the technology described in Patent Document 2, only one excitation amplifier can be connected to one waveguide antenna. Therefore, since the power is concentrated on one antenna, thermal countermeasures are required. In addition, if the frequency becomes higher, it is impossible to design a high-output amplifier. Therefore, it is expected to increase the output through parallel synthesis.

[0071] In contrast, the dielectric rod antenna 200 using the dielectric rod 100 of the present invention can connect an amplifier to each element because the excitation source is an array antenna. In the example of the attached figure, four amplifiers can be connected, so the output can be increased by 6dB. In this way, it is a structure suitable for antennas above millimeter waves where it is difficult to ensure output in a single amplifier. Unlike the dielectric rod antenna array described in non-patent document 1, it is not necessary to ground and adjust the dielectric separately, which not only reduces the cost of manufacturing and assembly, but also can cope with deviations caused by the impact during transportation through a single adjustment. That is, it is low-cost and easy to set up.

[0072] In this embodiment, the grid of dielectric rods 100 is one row. If it is combined with an array antenna, it becomes a dielectric rod antenna 200 that can correspond to four horizontal directions. Of course, the grid may be two-dimensional instead of one row.

[0073] As described above, by reducing the number of elements of the array antenna 300 of the excitation source, the transmission line is shortened, and relatively low loss is achieved compared to the past. In addition, by setting a dielectric designed in a form that the number of elements matches the number of beams used, an antenna that enables low loss, high gain, and beam scanning can be achieved. As a secondary effect, since the excitation source is an array antenna, if an amplifier is connected to each element, an increase in power due to parallel synthesis can be obtained.

[0074] Figure 3 This is an example of the results of the dielectric rod antenna 200 using the dielectric rod 100 of the present invention. Figure 4 This is an example of the result when there is only an excitation source antenna. The horizontal axis represents the angle, and the vertical axis represents the output.

[0075] like Figure 3 As shown, compared with the case of only the excitation source antenna, by converging the number of antennas to be equal to the number of beams, good high-gain multi-beam / beamforming performance can be obtained.

[0076] Specifically, in the maximum direction where the output of each unit antenna 301 is the maximum, it is possible to separate the unit antennas 301 under other conditions, that is, by a difference of 10 dB or more from other unit antennas. Specifically, a gain of 20.3 dBi at 27 degrees to the left and right, 22.3 dBi at 8 degrees to the left and right, and a maximum gain of 22 dBi or more is obtained. On the other hand, at 18 degrees to the left and right and 0 degrees, it is possible to overlap by 15 dBi or more.

[0077] That is, in this embodiment, a maximum gain of more than 22dBi is obtained. Furthermore, in the maximum direction, the difference from other conditions is more than 10dB. That is, separation of more than 10dB is possible. In addition, overlap of more than 15dBi is possible. In contrast, Figure 4As shown, such gain and overlap cannot be ensured in an antenna that is only an excitation source antenna and does not have the dielectric rod 100. Thus, compared with the case without the dielectric rod 100, the case with the dielectric rod 100 can enhance the gain by about 10 dB from 12.3 dBi to 22.1 dBi.

[0078] Figure 5 An example of a dielectric rod 100 according to an embodiment of the present invention is shown. Fig.12 , Fig.13 Indicates a side view.

[0079] The grid has m rows and n columns, where m and n are natural numbers greater than 2. As for the arrangement direction, the rows may be arranged in any direction such as the horizontal direction, the vertical direction, or the oblique direction.

[0080] In this embodiment, Figure 6 The array antenna combination shown is a dielectric rod antenna 200 in four vertical directions and four horizontal directions.

[0081] In this way, by changing the number of rods according to the number of elements, it is possible to contribute to increasing the gain of an arbitrary number of beams.

[0082] In one embodiment, if Figure 5 , Fig.12 , Fig.13 As shown, each main body 113 may be configured to be separated from each other from the base 111 toward the front end 112. According to this structure, efficient communication can be achieved in a wider range, for example, in both the horizontal direction and the vertical direction.

[0083] In one embodiment, the dielectric constant of the dielectric rod 100 is less than 4, and the length of the dielectric element 110 is more than 15 wavelengths. Here, the wavelength refers to the wavelength of the radio wave transmitted or received by the dielectric rod 100, that is, the wavelength of the radio wave transmitted or received by the array antenna.

[0084] According to this configuration, radio waves can be efficiently transmitted and received using the antenna.

[0085] Figure 7 An example of the dielectric element 110 included in the dielectric rod 100 according to one embodiment of the present invention is shown.

[0086] The main body 113 has a shape that tapers from the base 111 toward the front end 112, and the reduction rate of the diameter of the dielectric element relative to the length direction of the dielectric element increases toward the base side. In other words, when viewed relatively, it is a shape in which the seat ring is greatly reduced on the base side. Here, "the shape in which the main body 113 tapers from the base 111 toward the front end 112" may be a portion of approximately the same thickness, indicating a shape in which the portion connected to the front end 112 in the main body 113 is thinner than the portion connected to the base 111.

[0087] In this embodiment, the main body 113 is in a smooth curved shape, that is, the rod has a curved tapered shape.

[0088] Even a linear taper or a simple cylindrical shape can achieve high gain, but by forming it into a shape as shown in the drawing, a higher gain characteristic can be obtained.

[0089] By providing dielectrics, that is, rods, corresponding to the respective directions of the antenna element as shown in the drawings, it is possible to simultaneously achieve high gain and beam forming.

[0090] Figure 8 An example of the dielectric element 110 included in the dielectric rod 100 according to one embodiment of the present invention is shown.

[0091] The thickness of the main body 113 is a shape that changes in stages. However, in addition to becoming thinner toward the front end, it is also preferred that the length of the step is longer as the front end is approached. In other words, it is preferred that the thickness of the main body changes in stages, and the shape is longer as the front end is approached in each stage. In the embodiment, the step (stage) S1 at the front end is longer than the step (stage) S2 located on the base side.

[0092] Specifically, after designing the taper of the curve, a step-by-step approximation is performed based on it. Since the thickness changes in steps, the production can be simplified.

[0093] In one embodiment of the present invention, the dielectric rod 100 is transparent.

[0094] According to this configuration, light is transmitted through the dielectric rod 100 disposed on the front surface of the dielectric rod antenna 200, so that the state of the antenna element etc. can be checked. In addition, a configuration excellent in appearance can be realized.

[0095] Fig. 9 An example of a dielectric rod 100 according to an embodiment of the present invention is shown.

[0096] The dielectric rod 100 has a fixing portion 101 for fixing the positional relationship with the external antenna 400 .

[0097] The fixing portion 101 only needs to fix the positional relationship between the dielectric rod 100 and the antenna, and the dielectric rod 100 may be directly mounted on the antenna, or may be mounted on other locations such as a wall.

[0098] According to this configuration, the dielectric rod 100 can be easily fixed to the antenna.

[0099] Fig.10 An example of a dielectric rod antenna 200 according to an embodiment of the present invention is shown.

[0100] The dielectric rod antenna 200 includes any one of the above-mentioned dielectric rods 100 and an antenna unit 201 having a plurality of antenna elements. The plurality of antenna elements are, for example, Figure 2 Same structure.

[0101] Fig.11 A configuration example of the antenna unit 201 in the dielectric rod antenna 200 according to an embodiment of the present invention is shown.

[0102] In the dielectric rod antenna 200, the antenna unit 201 includes a transmitter 202 for transmitting radio waves with a frequency higher than the quasi-millimeter wave band, or a receiver 203 for receiving radio waves with a frequency higher than the quasi-millimeter wave band. Here, the frequency higher than the quasi-millimeter wave band refers to a frequency higher than 20 GHz.

[0103] Through the above structure, the present invention realizes a new dielectric rod antenna 200 and a dielectric rod 100, which, compared with the past: first, reduce the loss; second, can achieve at least the same antenna gain, that is, typically a maximum of more than 22dBi; third, can achieve at least the same beam scanning as the equivalent antenna.

[0104] The present invention is not limited to the above-described embodiments, and various embodiments are of course included within the scope not departing from the gist of the present invention.

[0105] For example, regarding the array arrangement of the excitation sources, the present technology can be applied not only to linear arrangement and quadrilateral arrangement but also to other arrangement methods such as triangular arrangement.

[0106] Explanation of symbols

[0107] 100 dielectric rods

[0108] 110 Dielectric Components

[0109] 111 base

[0110] 112 front end

[0111] 113 Main body

[0112] 101 Fixed Department

[0113] 200 dielectric rod antenna

[0114] 201 Antenna Department

[0115] 202 Sending Department

[0116] 203 Receiving Department

[0117] 300 array antenna

[0118] 301 unit antenna

[0119] 400 External Antenna

[0120] 410 antenna elements

Claims

1. A dielectric rod mounted on an external antenna, characterized in that: Having a plurality of dielectric elements, The plurality of dielectric elements are arranged in such a manner that at least one of the dielectric elements corresponds to each antenna element of the external antenna. The dielectric element comprises a base portion, a front end portion, and a main body portion connecting the base portion and the front end portion. The base is configured in a lattice shape, The main body has a shape extending substantially linearly from the base toward the front end. The main body portions are arranged to be separated from each other from the base portion toward the front end portion.

2. The dielectric rod according to claim 1, characterized in that: The grid is a column.

3. The dielectric rod according to claim 1, characterized in that: The grid has m rows and n columns, and m and n are natural numbers greater than 2.

4. The dielectric rod according to claim 3, characterized in that: All of the main body portions are arranged to be separated from each other in at least one direction from the base portion toward the front end portion.

5. The dielectric rod according to claim 3, characterized in that: All of the main body portions are arranged to be separated from each other from the base portion toward the front end portion.

6. The dielectric rod according to claim 1, characterized in that: The dielectric constant is less than 4, and the length of the dielectric element is more than 15 wavelengths.

7. The dielectric rod according to claim 1, characterized in that: The dielectric rod is transparent.

8. The dielectric rod according to claim 1, characterized in that: A fixing portion is provided for fixing the positional relationship with the antenna.

9. The dielectric rod according to any one of claims 1 to 7, characterized in that: The main body has a shape that tapers from the base toward the front end, and a reduction rate of a diameter of the dielectric element with respect to a longitudinal direction of the dielectric element increases toward the base.

10. The dielectric rod according to claim 7, characterized in that: The main body is in a smooth curve shape.

11. The dielectric rod according to any one of claims 1 to 7, characterized in that: The thickness of the main body portion changes in stages, and becomes longer toward the front end in each stage.

12. A dielectric rod antenna, characterized in that: have: The dielectric rod according to any one of claims 1 to 7; and An antenna unit includes a plurality of antenna elements.

13. The dielectric rod antenna according to claim 12, characterized in that: It includes a transmitting unit for transmitting radio waves of millimeter waves or higher, or a receiving unit for receiving radio waves of millimeter waves or higher.

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