28GHz high-gain array antenna applied to NR-V2X

Abstract

The invention belongs to the technical field of communication, and particularly relates to a 28GHz high-gain array antenna applied to NR-V2X. According to the 28GHz high-gain array antenna applied to the NR-V2X, a plurality of micro-strip antennas are arranged in an array, the micro-strip antennas are symmetrically distributed relative to a central axis of a substrate, and the micro-strip antennas on the same side of the central axis of the substrate are arranged in a 4 * 4 mode and are distributed at equal intervals. According to the millimeter wave micro-strip array, the current ratio of the four micro-strip antennas from far to near on the same side and in the same row is controlled to be 1: 1: 2: 4, the gain can be effectively improved, the transmission loss can be effectively reduced, and compared with a common antenna in a high frequency band, the problems that the transmission loss is large and the radiation radius is small can be effectively solved. A signal can have a high-gain and high-directivity wave beam, so that the defect of relatively large attenuation of millimeter wave long-distance communication is overcome.

Description

Technical Field

[0001] The present invention belongs to the field of communication technology, and specifically relates to a 28 GHz high-gain array antenna used in NR-V2X. Background Art

[0002] At present, in the application of antennas, the use of millimeter wave frequency bands has high transmission loss, which poses a major challenge to high-frequency wireless access. These transmission losses include path transmission loss, wall penetration loss, rain attenuation, and even transmission loss caused by water vapor and oxygen absorption, resulting in a short radiation radius and particularly unsatisfactory indoor signal coverage. In NR-V2X advanced applications, with the collection and processing of vehicle information, environmental information, etc., the amount of data stored in the system will increase, and the amount of data will continue to grow over time. In this context, if traditional antennas are still used, they cannot meet the transmission needs of massive data. Therefore, in order to solve the above problems in NR-V2X applications, we provide a 28GHz high-gain array antenna for NR-V2X. Summary of the invention

[0003] The purpose of the present invention is to provide a 28 GHz high-gain array antenna applied to NR-V2X to solve the problems mentioned in the background technology.

[0004] In order to achieve the above technical objectives, the technical solution adopted by the present invention is as follows:

[0005] A 28 GHz high-gain array antenna used in NR-V2X, comprising a substrate, on which 32 microstrip antennas are arrayed, the microstrip antennas are symmetrically distributed relative to the centerline axis of the substrate, and the microstrip antennas on the same side of the centerline axis of the substrate are equidistantly distributed in a 4*4 arrangement;

[0006] A feeder line group is disposed on the substrate, and the feeder line group connects all the microstrip antenna circuits.

[0007] The feed line group includes a main line and 8 branch lines. The main line is located in the middle of the substrate. A feeding point is arranged at the center of the main line. The branch lines are matched in a row with the microstrip antennas in the same row on one side of the central axis of the substrate. The branch lines are all connected to the main line and are evenly distributed on both sides of the feeding point.

[0008] An extension line is connected between the branch line and the microstrip antenna, and impedance transformers are provided on the input sides of the intersections of the extension line and the branch line as well as the intersection of the branch line and the main line. The current ratio of the four microstrip antennas on the same side of the central axis of the substrate and in the same row from far to near is 1:1:2:4, and the impedances of the microstrip antennas in the same column to the feeding point are the same.

[0009] The operating indicators of the microstrip antenna array are:

[0010] The operating frequency is 28GHZ±0.45GHz;

[0011] VSWR < 2 within the working frequency band;

[0012] Half-power lobe width of E and H planes>20°;

[0013] Gain>21dB;

[0014] The polarization mode is linear polarization;

[0015] The input impedance of the feed point is 50Ω.

[0016] The substrate model is RO5880, the dielectric constant is 2.2, and the loss tangent tan=0.0009.

[0017] Compared with the prior art, the present invention has at least the following advantages:

[0018] By using multiple microstrip antennas arranged in an array in the present application, the current ratio of the four microstrip antennas on the same side and in the same row of the central axis of the substrate from far to near is set at 1:1:2:4, so that the electric field of the microstrip antenna closer to the center is stronger, and the electric field of the microstrip antennas on the same side and in the same row increases exponentially as it moves closer to the center, which can effectively improve the gain and reduce the transmission loss. Compared with the problems of large transmission loss and small radiation radius of ordinary antennas in the high frequency band, this can be effectively solved. Through this millimeter-wave microstrip reflection array, the signal travel can have a high-gain, high-directivity beam, thereby overcoming the defect of large attenuation in millimeter-wave long-distance communications. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention is further illustrated by means of the non-limiting examples given in the accompanying drawings.

[0020] Figure 1 Schematic diagram of the array structure of the antenna of the present invention.

[0021] Figure 2 It is a schematic diagram of the microstrip antenna structure of the antenna of the present invention.

[0022] Figure 3 It is a schematic diagram of the structure of the feeder group of the antenna of the present invention.

[0023] Figure 4 for Figure 3 A schematic diagram of the enlarged structure at point A in the middle.

[0024] Figure 5 This is the standing wave ratio diagram of the antenna of the present invention before matching.

[0025] Figure 6 This is the standing wave ratio diagram of the antenna of the present invention after matching.

[0026] Figure 7 : is the radiation pattern of the antenna of the present invention.

[0027] Figure 8 3D radiation pattern of the antenna of the present invention.

[0028] Fig. 9 Schematic diagram of the electric field strength of the antenna of the present invention. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0030] Example 1

[0031] like Figure 1-2 As shown, a 28 GHz high-gain array antenna used in NR-V2X includes a substrate 1, on which 32 microstrip antennas 2 are arrayed, the microstrip antennas 2 are symmetrically distributed relative to the central axis of the substrate 1, and the microstrip antennas 2 on the same side of the central axis of the substrate 1 are equidistantly distributed in a 4*4 arrangement;

[0032] The microstrip antennas 2 are evenly and symmetrically arranged to facilitate regular distribution and arrangement. The 32 microstrip antennas 2 are arranged to satisfy the symmetrical arrangement relative to the feeding point and to facilitate the single-side array arrangement. The antenna array AA (Antenna Array) with a large number or a large number of antenna units is designed, and the antenna access point AP (Access Point) of each antenna unit in the antenna array is properly designed to be in phase to generate positive coupling. At this time, the radiation direction of the array antenna after positive coupling will become a thinner radiation beam that gathers energy, and therefore has a larger antenna gain. This is the so-called beamforming technology, which is used to solve the large transmission loss of millimeter waves in transmission.

[0033] Because the more antenna elements AE (Antenna element) there are in the antenna array, the narrower the half-power beam width HPBW (Half-Power Beam Width) of the formed beam is, and the greater the gain of the array antenna is. Every time the number of AE in the antenna array doubles, the gain of the array antenna increases by 3dB. Therefore, considering the relationship between the exponential increase in the number of microstrip antenna arrays and the gain value of the array antenna, an array of 32 microstrip antennas is the best choice.

[0034] A feeder group 3 is provided on the substrate 1, and the feeder group 3 connects all microstrip antenna circuits.

[0035] The feeding line group 3 includes a main line 31 and 8 branch lines 32. The main line 31 is located in the middle of the substrate. A feeding point 5 is provided in the center of the main line 31. The branch lines 32 are matched in a row with the microstrip antennas 2 in the same row on one side of the central axis of the substrate 1. The branch lines 32 are all connected to the main line 31, and the branch lines 32 are evenly distributed on both sides of the feeding point 5.

[0036] An extension line is connected between the branch line and the microstrip antenna, and an impedance transformer is provided at the input side of the intersection of the extension line and the branch line and the intersection of the branch line and the main line. The current ratio of the four microstrip antennas 2 from far to near on the same side of the linear axis in the substrate 1 and in the same row is 1:1:2:4, and the impedance of the microstrip antennas 2 in the same row to the feeding point 5 is the same. The impedance transformer is used to adjust the impedance value of each microstrip antenna to the feeding point 5 to ensure that the current ratio of the four microstrip antennas 2 from far to near on the same side of the linear axis in the substrate 1 and in the same row is 1:1:2:4.

[0037] The current ratio of the four microstrip antennas 2 on the same side and in the same row of the central axis of the substrate 1 from far to near is 1:1:2:4, so that the electric field of the microstrip antenna closer to the center is stronger, and the electric field of the microstrip antennas on the same side and in the same row increases exponentially, the electric field is evenly distributed, and the gain can be improved.

[0038] The operating specifications of the microstrip antenna array are:

[0039] The operating frequency is 28GHZ±0.45GHz;

[0040] VSWR < 2 within the working frequency band;

[0041] Half-power lobe width of E and H planes>20°;

[0042] Gain>21dB;

[0043] The polarization mode is linear polarization;

[0044] The input impedance of the feed point is 50Ω.

[0045] The substrate model is RO5880, the dielectric constant is 2.2, and the loss tangent tan=0.0009.

[0046] Embodiment 2

[0047] like Figure 3-8 As shown, the array antenna matching values ​​are shown in Table 1.

[0048] Table 1 Array antenna matching values

[0049]

[0050] Fig. 9 It can be seen that the potential difference of the antenna is higher towards the center and lower towards the edge, and it increases exponentially. Figure 6 The standing wave ratio before matching is shown in the figure. The large standing wave before matching indicates low gain. Figure 7 To match the standing wave ratio, Figure 6 , 7 By comparison, it can be seen that the standing wave ratio of the electrical port of the series-parallel feeding network of the 28GHz broadband array antenna is reduced from 20.48 to 1.18, the loss is reduced, and the gain is increased. Figure 8 The gain of this antenna can also be seen in the radiation diagram, where Hm1 is 21.13, and from the 3D radiation diagram it can be seen that the gain of the antenna reaches 21.8dBi. Due to the large overall bandwidth of the microstrip array reflective antenna and the half-power lobe width of the E and H planes, the microstrip reflective antenna array and beamforming can reduce the transmission of massive data and high latency in NR-V2X.

[0051] By setting multiple microstrip antennas in the array of the present application, the current ratio of four microstrip antennas 2 from far to near on the same side of the line axis in the same row of the impedance adjustment substrate 1 is 1:1:2:4, which can effectively improve the gain and reduce the transmission loss. Compared with the problems of large transmission loss and small radiation radius of ordinary antennas in the high frequency band, it can be effectively solved. Through this millimeter-wave microstrip reflection array, the signal travel can have a high-gain, high-directivity narrow beam, thereby overcoming the defect of large attenuation of millimeter-wave long-distance communication. Since the array antenna is composed of multiple array elements, part of the energy of the array element will be coupled to the adjacent unit when receiving or transmitting the signal, so the array element spacing is kept at least 0.5 times the wavelength to reduce coupling, so the unit spacing is usually taken as 0.5λ <d<λ;

[0052] The material of the substrate can be adjusted according to the actual situation. For example, if the EBG structure is used, the frequency range showing the band-stop characteristic can be adjusted by adjusting the size and height of the via hole of the ground plate. This band-stop characteristic can be used to improve the isolation between the transmitting antenna and the receiving antenna, thereby reducing the overall size of the antenna and achieving miniaturization.

[0053] Furthermore, the EBG structure can be equivalent to a parallel LC resonant circuit, which uses the high magnetic loss characteristics of magnetic materials to achieve wide-band wave absorption capabilities and improve isolation. The polarization grating can transmit polarized electromagnetic waves perpendicular to the grid lines and reflect electromagnetic waves parallel to the grid lines. The polarization grating structure can be used to suppress electromagnetic waves with polarization parallel to the array surface and improve isolation. In this way, the antenna can effectively improve data transmission in high-bandwidth loans and meet the needs of low-latency data transmission.

[0054] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A 28 GHz high-gain array antenna used in NR-V2X, comprising a substrate (1), characterized in that: The substrate (1) is provided with 32 microstrip antennas (2) in an array, the microstrip antennas (2) are symmetrically distributed relative to the centerline axis of the substrate (1), and the microstrip antennas (2) on the same side of the centerline axis of the substrate (1) are equidistantly distributed in a 4*4 arrangement; A feeder line group (3) is provided on the substrate (1), and the feeder line group (3) connects all the microstrip antenna circuits.

2. According to claim 1, a 28 GHz high-gain array antenna used in NR-V2X, characterized in that: The feed line group (3) comprises a main line (31) and eight branch lines (32), wherein the main line (31) is located in the middle of a substrate, a feeding point (5) is provided at the center of the main line (31), and the branch lines (32) are matched in a row with the microstrip antennas (2) in the same row on one side of the central axis of the substrate (1), and the branch lines (32) are all connected to the main line (31), and the branch lines (32) are evenly distributed on both sides of the feeding point (5).

3. The 28 GHz high-gain array antenna used in NR-V2X according to claim 2, characterized in that: An extension line is connected between the branch line and the microstrip antenna, and impedance transformers are provided at the input sides of the intersections of the extension line and the branch line, and of the branch line and the main line. The current ratio of the four microstrip antennas (2) on the same side of the centerline axis of the substrate (1) and in the same row from far to near is 1:1:2:4, and the currents of the microstrip antennas (2) in the same row are the same.

4. The 28 GHz high gain array antenna used in NR-V2X according to claim 3, characterized in that: The operating indicators of the microstrip antenna array are: The operating frequency is 28GHZ±0.45GHz; VSWR < 2 within the working frequency band; Half-power lobe width of E and H planes>20°; Gain>21dB; The polarization mode is linear polarization; The input impedance of the feed point is 50Ω.

5. The 28 GHz high-gain array antenna used in NR-V2X according to claim 4, characterized in that: The substrate model is RO5880, the dielectric constant is 2.2, and the loss tangent tan=0.0009.

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