阅读说明：本技术 一种加载l型枝节的圆极化毫米波微带天线 (Circular polarization millimeter wave microstrip antenna loaded with L-shaped branches ) 是由 严冬 程威 王平 陈逸飞 郭琪富 杭锐 于 2020-06-29 设计创作，主要内容包括：本发明涉及一种加载L型枝节的圆极化毫米波微带天线,属于无线通信领域。天线属于单层结构,天线辐射面和馈线结构分别位于介质板的上下表面。包括RT/duroid 5880介质基板、方形槽、一对倒L型微扰条以及锤形微带馈线；方形槽位于介质板上的天线辐射表面,方形槽的外边界与介质板的边界重合；两个倒L型微扰条分别位于方形槽的对角处,且与方形槽相连接；锤形微带馈线位于介质板的下表面,处于介质板中间偏右位置,馈线底部与介质板边界接触,形成天线的馈电端。本天线的工作频段位于5G FR2频段之内,阻抗带宽提升明显,圆极化辐射性能良好,结构简单,尺寸较小,具有一定的应用价值。(The invention relates to a circularly polarized millimeter wave microstrip antenna loaded with L-shaped branches, and belongs to the field of wireless communication. The antenna belongs to a single-layer structure, and the antenna radiation surface and the feeder structure are respectively positioned on the upper surface and the lower surface of the dielectric plate. The micro-strip antenna comprises an RT/duroid5880 dielectric substrate, a square groove, a pair of inverted L-shaped micro-disturbance strips and a hammer-shaped micro-strip feeder line; the square groove is positioned on the antenna radiation surface of the dielectric plate, and the outer boundary of the square groove is overlapped with the boundary of the dielectric plate; the two inverted L-shaped perturbation strips are respectively positioned at the opposite corners of the square groove and are connected with the square groove; the hammer-shaped microstrip feeder is positioned on the lower surface of the dielectric plate and is positioned at the right position in the middle of the dielectric plate, and the bottom of the feeder is contacted with the boundary of the dielectric plate to form a feed end of the antenna. The working frequency band of the antenna is located within the frequency band of 5G FR2, the impedance bandwidth is obviously improved, the circularly polarized radiation performance is good, the structure is simple, the size is small, and the antenna has a certain application value.)

1. The utility model provides a circular polarization millimeter wave microstrip antenna of loading L type minor matters which characterized in that: the micro-strip antenna comprises an RT/duroid5880 dielectric substrate, a square groove, two inverted L-shaped micro-disturbance strips and a hammer-shaped micro-strip feeder line;

the square groove is positioned on the antenna radiation surface of the dielectric plate, and the outer boundary of the square groove is overlapped with the boundary of the dielectric plate;

the two inverted L-shaped perturbation strips are respectively positioned at the opposite corners of the square groove and are connected with the square groove;

the hammer-shaped microstrip feeder is positioned on the lower surface of the dielectric plate and is positioned at the right position in the middle of the dielectric plate, and the bottom of the feeder is contacted with the boundary of the dielectric plate to form a feed end of the antenna;

the square groove and the two inverted-L-shaped perturbation strips on the radiating surface of the antenna are used for exciting two orthogonal modes with the same amplitude and 90-degree phase difference, so that the circularly polarized wave is radiated.

2. The circularly polarized millimeter wave microstrip antenna loaded with L-shaped branches according to claim 1, wherein: the working frequency band of the antenna is within the 5G FR2 frequency band, and the resonant frequency is 24.4 GHz.

3. The circularly polarized millimeter wave microstrip antenna loaded with L-shaped branches according to claim 1, wherein: the hammer-shaped microstrip feeder line on the lower surface of the dielectric substrate is not positioned on the same plane with the radiating surface of the antenna, and energy is transferred to the radiating surface of the antenna in a mode of proximity coupling feeding, so that the bandwidth of the antenna is effectively expanded.

4. The circularly polarized millimeter wave microstrip antenna loaded with L-shaped branches according to claim 1, wherein: the square groove is positioned on the radiating surface of the antenna and is of a square structure, and the side length is 5.5 mm; the length of the inverted L-shaped perturbation strip positioned at the opposite angle of the square groove is 2.2mm, and the width of the inverted L-shaped perturbation strip is 1.6 mm.

5. The circularly polarized millimeter wave microstrip antenna loaded with L-shaped branches according to claim 1, wherein: the microstrip feeder line is of a hammer-shaped structure with the lower width of 0.65mm, the upper width of 0.904mm and the height of 2.65 mm; the center of the microstrip feeder line structure is located at the position 0.225mm on the right side of the center line of the square dielectric substrate.

Technical Field

The invention belongs to the field of wireless communication, and relates to a circularly polarized millimeter wave microstrip antenna loaded with L-shaped branches.

Background

Fifth generation (5G) mobile communication technology is rapidly developing and popularizing. Compared with 4G and 5G communication, the method has the advantages of high speed, ultralow time delay, large capacity, high reliability and the like, and can meet the increasing data transmission requirements of the current society. The 5G communication standard takes the millimeter wave frequency band as its FR2 communication frequency band for the first time, thereby providing an excellent data transmission speed and an ultra-large capacity for a 5G network. Therefore, research and design of millimeter wave antennas for 5G mobile devices has been a research focus in recent years.

Compared with a linear polarization antenna, the circularly polarized antenna has the advantages of reducing polarization mismatch, effectively inhibiting millimeter wave multipath effect and the like, so that the circularly polarized antenna is more suitable for wireless communication from equipment to equipment (D2D) in a 5G network.

The existing technical schemes for designing circularly polarized millimeter wave antennas are many, and some of them are listed here: first, a circularly polarized radiation characteristic is excited by two parallel electric and magnetic dipoles excited with a phase difference of 90 °. Second, a circularly polarized radiation pattern is generated by a conformal polarizer with a double circular lens. And thirdly, adding a special-shaped ring structure on the Archimedes spiral radiator to radiate circularly polarized waves.

The diameter of the antenna in the first technical scheme is only 0.38mm, the structure is simple, the resonance frequency is 28GHz, but the impedance bandwidth is narrow and is only 8%.

Secondly, the antenna in the technical scheme has the resonant frequency of 29GHz and the impedance bandwidth of 34.5 percent (24 GHz-32 GHz). However, the structure of the antenna is too complex, the antenna object needs to be completed by means of 3D printing, the manufacturing process is complex, and the actual engineering application value of the antenna is low.

Third, the impedance bandwidth of the antenna in the technical scheme can reach 46.63%, and the gain is 6.49dBi at most, but the physical size of the antenna is large, and the length reaches 30mm, which is not beneficial to the integration of the antenna into the communication equipment.

Disclosure of Invention

In view of this, the present invention provides a circularly polarized millimeter wave microstrip antenna loaded with L-shaped branches, which solves the problems of narrow bandwidth and complex structure of the antenna.

In order to achieve the purpose, the invention provides the following technical scheme:

a circularly polarized millimeter wave microstrip antenna loaded with L-shaped branches comprises an RT/duroid5880 dielectric substrate, a square groove, two inverted L-shaped perturbation strips and a hammer-shaped microstrip feeder line;

the square groove is positioned on the antenna radiation surface of the dielectric plate, and the outer boundary of the square groove is overlapped with the boundary of the dielectric plate;

the two inverted L-shaped perturbation strips are respectively positioned at the opposite corners of the square groove and are connected with the square groove;

the hammer-shaped microstrip feeder is positioned on the lower surface of the dielectric plate and is positioned at the right position in the middle of the dielectric plate, and the bottom of the feeder is contacted with the boundary of the dielectric plate to form a feed end of the antenna;

the square groove and the two inverted-L-shaped perturbation strips on the radiating surface of the antenna are used for exciting two orthogonal modes with the same amplitude and 90-degree phase difference, so that the circularly polarized wave is radiated.

Optionally, the operating frequency band of the antenna is within a 5G FR2 frequency band, and the resonant frequency is 24.4 GHz.

Optionally, the hammer-shaped microstrip feeder on the lower surface of the dielectric substrate is not located on the same plane as the antenna radiation surface, and energy is transferred to the antenna radiation surface in a proximity coupling feeding manner, so that the antenna bandwidth is effectively expanded.

Optionally, the square groove is located on the radiating surface of the antenna, and is of a square structure, and the side length is 5.5 mm; the length of the inverted L-shaped perturbation strip positioned at the opposite angle of the square groove is 2.2mm, and the width of the inverted L-shaped perturbation strip is 1.6 mm.

Optionally, the microstrip feeder line is of a hammer-shaped structure with a lower width of 0.65mm, an upper width of 0.904mm and a height of 2.65 mm; the center of the microstrip feeder line structure is located at the position 0.225mm on the right side of the center line of the square dielectric substrate.

The invention has the beneficial effects that: the invention adopts the proximity coupling feed technology, the antenna microstrip feed line and the radiation surface are not in the same plane, the bottom feed line and the antenna radiation surface have the capacitive coupling effect, and meanwhile, the periphery of the bottom feed line is in an open state, so that the impedance bandwidth is obviously improved. Meanwhile, two 90-degree L-shaped branches are loaded on the radiation surface of the antenna to radiate circularly polarized waves, so that the circularly polarized radiation performance is good, and the structure of the antenna is simplified. The antenna size is only 5.5 x 0.127mm, and the antenna has the advantages of miniaturization and easy integration. The structure is a single-layer structure, and the processing and manufacturing difficulty is small.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the means of the instrumentalities and combinations particularly pointed out hereinafter.

Drawings

For the purposes of promoting a better understanding of the objects, aspects and advantages of the invention, reference will now be made to the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic view of an antenna radiation surface structure;

FIG. 2 is a schematic diagram of a microstrip feed line structure at the bottom of an antenna;

FIG. 3 is a side view of an antenna structure;

FIG. 4 is a graph of antenna return loss S11;

FIG. 5 is a graph of antenna axial ratio AR;

FIG. 6 is an antenna gain diagram;

FIG. 7 is an antenna radiation pattern (24.4GHz, XOZ);

fig. 8 shows the antenna radiation pattern (24.4GHz, YOZ).

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention in a schematic way, and the features in the following embodiments and examples may be combined with each other without conflict.

Wherein the showings are for the purpose of illustrating the invention only and not for the purpose of limiting the same, and in which there is shown by way of illustration only and not in the drawings in which there is no intention to limit the invention thereto; to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there is an orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "rear", etc., based on the orientation or positional relationship shown in the drawings, it is only for convenience of description and simplification of description, but it is not an indication or suggestion that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes, and are not to be construed as limiting the present invention, and the specific meaning of the terms may be understood by those skilled in the art according to specific situations.

As shown in fig. 1-3, the circularly polarized millimeter wave microstrip antenna loaded with L-shaped branches provided by the invention comprises an RT/duroid5880 dielectric substrate, a square slot, a pair of inverted-L-shaped perturbation strips and a hammer-shaped microstrip feeder line; the square groove is positioned on the antenna radiation surface of the dielectric plate, and the outer boundary of the square groove is overlapped with the boundary of the dielectric plate; the two inverted L-shaped perturbation strips are respectively positioned at the opposite corners of the square groove and are connected with the square groove; the hammer-shaped microstrip feeder is positioned on the lower surface of the dielectric plate and is positioned at the right position in the middle of the dielectric plate, and the bottom of the feeder is contacted with the boundary of the dielectric plate to form a feed end of the antenna;

the square groove and the pair of inverted L-shaped perturbation strips on the radiation surface of the antenna are used for exciting two orthogonal modes with the same amplitude and 90-degree phase difference so as to radiate circularly polarized waves;

the working frequency band of the antenna is within the 5G FR2 frequency band, and the resonant frequency is 24.4 GHz.

The hammer-shaped microstrip feeder line on the lower surface of the dielectric substrate is not positioned on the same plane with the radiating surface of the antenna, and energy is transferred to the radiating surface of the antenna in a mode of proximity coupling feeding, so that the bandwidth of the antenna is effectively expanded.

The length of each part of the circularly polarized millimeter wave microstrip antenna loaded with the L-shaped branches is in units of (mm) as shown in Table 1.

TABLE 1 Length of each part of circularly polarized millimeter wave microstrip antenna

Wherein, the square groove that is located antenna radiation surface is 5.5 mm's square structure, and the type of falling L perturbation strip that is located square groove diagonal department is 2.2mm, and the width is 1.6 mm.

The microstrip feeder line is of a hammer-shaped structure with the lower width of 0.65mm, the upper width of 0.904mm and the height of 2.65 mm; the center of the microstrip feeder line structure is located at the position 0.225mm on the right side of the center line of the square dielectric substrate.

The circularly polarized millimeter wave microstrip antenna has a simple structure and good circularly polarized radiation performance. The main parameter indexes of the circularly polarized millimeter wave microstrip antenna are return loss (S11) and Axial Ratio (AR). S11 parametric diagram as shown in fig. 4, it can be derived from fig. 4 that the resonant frequency of the antenna is 24.4GHz and the return loss at the resonant frequency is-32.79 dB. The relative bandwidth with return loss less than-10 dB is 25.8% (21.13 GHz-27.43 GHz); as shown in FIG. 5, the AR parameter graph shows that the relative bandwidth of the axial ratio AR less than 3dB is 47.1% and the frequency range is 17.99GHz to 29.5GHz from FIG. 5. In addition, as can be seen from fig. 8, the frequency band with the return loss of the antenna less than-10 dB is 21.13GHz to 27.43GHz, so that the frequency band with the antenna axial ratio less than 3dB just covers the frequency band with the return loss S11 less than-10 dB.

The gain of the antenna is shown in fig. 6, and it can be understood from fig. 6 that the gain of the antenna is at least 3.93dBi in the frequency range (21.13GHz 27.43GHz) in which the return loss S11 of the antenna is less than-10 dB, and at most 4.32dBi at the resonant frequency of 24.4 GHz.

The far field patterns of the inventive circularly polarized antenna having a resonant frequency of 24.4GHz in the XOZ plane and the YOZ plane are shown in fig. 7 and 8. As can be seen from the figure, the antenna radiates left-handed circularly polarized (LHCP) waves in the positive semi-axis direction of the Z-axis, and radiates right-handed circularly polarized (RHCP) waves in the negative semi-axis direction of the Z-axis, and the circularly polarized radiation performance is good.

Finally, the above embodiments are only intended to illustrate the technical solutions of the present invention and not to limit the present invention, and although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions, and all of them should be covered by the claims of the present invention.