Antenna and unmanned aerial vehicle

Antenna and UAV

Technical field

The invention relates to the technical field of antennas, in particular to an antenna and an unmanned aerial vehicle.

Background technique

The antenna is an important device for space signal transmission. With the popularization of smart devices and the demand for miniaturization of the size of smart devices, the requirements for miniaturization of the antenna size are getting higher and higher. The current antenna miniaturization design method will increase the physical weight of the antenna or cause the loss of the antenna's performance. Take dipole antennas as an example. At present, dipole antennas are usually miniaturized by bending or increasing the dielectric constant of the dielectric substrate and the thickness of the plate, but this miniaturization method will reduce the bandwidth of the antenna or increase the antenna weight.

Summary of the invention

The embodiment of the present invention provides an antenna and an unmanned aerial vehicle.

The antenna of the embodiment of the present invention includes a feeding point, a high-frequency radiation unit, and a low-frequency radiation unit. One end of the high-frequency radiation unit is connected to the feeding point. The low-frequency radiation unit includes a first low-frequency connection section, an inductor, and a second low-frequency connection section. The second low-frequency connection sections are sequentially connected, and the width of the second low-frequency connection section gradually widens from the start end of the connection with the inductance to the end of the second low-frequency connection section.

The unmanned aerial vehicle of the embodiment of the present invention includes an unmanned aerial vehicle body and an antenna. The antenna is arranged on the drone body. The antenna includes a feeding point, a high-frequency radiation unit and a low-frequency radiation unit. One end of the high-frequency radiation unit is connected to the feeding point. The low-frequency radiation unit includes a first low-frequency connection section, an inductor, and a second low-frequency connection section. The second low-frequency connection sections are sequentially connected, and the width of the second low-frequency connection section gradually widens from the start end of the connection with the inductance to the end of the second low-frequency connection section.

The antenna and the drone of the embodiment of the present invention increase the inductance in the low-frequency radiation unit, and design the width of the low-frequency radiation unit into a form of gradual width, so that the antenna can be miniaturized, and the bandwidth of the antenna can be increased, and the antenna's performance can be improved. performance.

The additional aspects and advantages of the embodiments of the present invention will be partly given in the following description, and part of them will become obvious from the following description, or be understood through the practice of the embodiments of the present invention.

Description of the drawings

The above and/or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, in which:

FIG. 1 is a schematic diagram of the structure of an antenna according to some embodiments of the present invention.

Fig. 2 is an impedance diagram of an antenna according to some embodiments of the present invention.

Fig. 3 is a diagram of standing wave ratio of antennas according to some embodiments of the present invention.

Fig. 4 is a directional diagram of a low-frequency radiation unit of an antenna according to some embodiments of the present invention.

Fig. 5 is a directivity diagram of a high-frequency radiation unit of an antenna according to some embodiments of the present invention.

Fig. 6 is a schematic diagram of the structure of an unmanned aerial vehicle according to some embodiments of the present invention.

Detailed ways

The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings, in which the same or similar reference numerals indicate the same or similar elements or elements with the same or similar functions. The following embodiments described with reference to the accompanying drawings are exemplary, and are only used to explain the present invention, and cannot be understood as a limitation to the present invention.

Please refer to FIG. 1, the present invention provides an antenna 100. The antenna 100 includes a feeding point 10, a high-frequency radiation unit 20 and a low-frequency radiation unit 30. One end of the high-frequency radiation unit 20 is connected to the feeding point 10. The low-frequency radiation unit 30 includes a first low-frequency connection section 31, an inductor 33 and a second low-frequency connection section 35. One end of the first low-frequency connection section 31 is connected to the feeding point 10. The first low-frequency connection section 31, the inductor 33, and the second low-frequency connection section 35 are connected in sequence. The width of the second low-frequency connection section 35 gradually widens from the start end A connected to the inductor 33 to the end B of the second low-frequency connection section 35.

Specifically, the antenna 100 is a dipole antenna, the number of high-frequency radiation units 20 is two, and the number of low-frequency radiation units 32 is also two.

The feeding point 10 includes a feeding point 11 and a grounding point 13. As shown in FIG. 1, the feed point 11 is located in the left half of the antenna 100, and the ground point 13 is located in the right half of the antenna 100. The feed point 10 is an interface between the antenna 100 and the feeder, and is used to connect the antenna 100 and the feeder. The feeder connects the antenna 100 and the transceiver system. When the antenna 100 is used as a transmitting antenna, the transmitter in the transceiver system outputs high-frequency current energy (or guided wave energy), and the high-frequency current energy is transmitted to the antenna 100 through the feeder, and the antenna 100 converts the high-frequency current energy into electromagnetic wave energy and radiates into space. middle. When the antenna 100 is used as a receiving antenna, the antenna 100 converts electromagnetic wave signals transmitted from space into high-frequency current energy (or guided wave energy), and the high-frequency current energy is transmitted to the receiver through the feeder.

Each high-frequency radiation unit 20 includes two high-frequency radiation parts 21. The two high-frequency radiation parts 21 in each radiation unit 20 are symmetrical with respect to the low-frequency radiation unit 30. Wherein, each high-frequency radiation part 21 includes a first high-frequency connection section 211 and a second high-frequency connection section 213, one end of the first high-frequency connection section 211 is connected to the feeding point 10, and the first high-frequency connection section 211 The other end of is connected to the second high-frequency connection section 213. Each first high-frequency connection section 211 is perpendicular to the extension direction of the low-frequency radiation unit 30, and each second high-frequency connection section 213 is consistent with and parallel to the extension direction of the low-frequency connection section 30. Specifically, in the antenna 100 shown in FIG. 1, the two high-frequency radiation parts 21 on the left are symmetrical with respect to the low-frequency radiation unit 30 on the left, and the two high-frequency radiation parts 21 on the right are symmetrical with respect to the low-frequency radiation unit on the right. 30 symmetry. In the high-frequency radiation unit 20 on the left, one end of the two first high-frequency connection segments 211 is connected to the feed point 11; in the high-frequency radiation unit 20 on the right, one end of the two first high-frequency connection segments 211 Both are connected to the ground point 13.

In this way, the first high-frequency connection section 211 is designed to be perpendicular to the extension direction of the low-frequency radiation unit 30, and the second high-frequency connection section 213 is designed to be consistent and parallel to the extension direction of the low-frequency radiation unit 30, which can be increased on the one hand. The interval between the high-frequency radiation unit 20 and the low-frequency radiation unit 30 can correspondingly reduce the mutual influence between the high-frequency radiation unit 20 and the low-frequency radiation unit 30, and ensure that both the high-frequency radiation unit 20 and the low-frequency radiation unit 30 have good performance. The radiation performance. In addition, by providing two high-frequency radiation parts 21 symmetrical about the low-frequency radiation unit 30 in each high-frequency radiation unit 20, the symmetry of the structure of the antenna 100 can be increased, and the impedance between the high-frequency radiation unit 20 and the feeder can be improved. Matching, reducing the standing wave ratio, and improving the radiation performance of the high-frequency radiation unit 20.

Each low-frequency radiation unit 30 is composed of a first low-frequency connection section 31, an inductor 33, and a second low-frequency connection section 35, and the first low-frequency connection section 31, the inductor 33 and the second low-frequency connection section 35 are connected in sequence. Specifically, in the low-frequency radiation unit 30 on the left, one end of the first low-frequency connection section 31 is connected to the feeding point 11, the other end of the first low-frequency connection section 31 is connected to the inductor 33, and the inductance 33 is connected to the first low-frequency connection section. The opposite end of 31 is connected to the second low frequency connection section 35. In the low-frequency radiation unit 30 on the right, one end of the first low-frequency connection section 31 is connected to the ground point 13, the other end of the first low-frequency connection section 31 is connected to the inductor 33, and the end of the inductor 33 opposite to the first low-frequency connection section 31 Connected to the second low-frequency connection section 35.

Among them, the length of the first low-frequency connection section 31 is adjustable. Specifically, for the low-frequency radiation unit 30 on the left side of the antenna 100, the distance between the end point of the inductance 33 and the first low-frequency connection section 31 and the feeding point 11 is adjustable. For the unit 30, the distance between the end point of the inductor 33 and the first low-frequency connection section 31 and the ground point 13 is adjustable. The length of the first low-frequency connection section 31 is related to the inductance value of the antenna 100. It is understandable that in the antenna design, when the total length of the low-frequency radiation part of the antenna is a quarter of the wavelength of the electromagnetic wave radiated by the low-frequency radiation part, the antenna is purely resistive and will not reflect high-frequency current energy back to the signal source. , The radiation efficiency of the antenna is higher. However, in the miniaturized design of the antenna, if the total length of the low-frequency radiation part of the antenna is directly reduced, so that the total length of the low-frequency radiation part is less than one-fourth of the wavelength of the electromagnetic wave radiated by the low-frequency radiation part, this will cause the antenna The impedance is capacitive, and the high-frequency current energy transmitted to the antenna via the feeder will be reflected back to the signal source, resulting in a significant decrease in the radiation efficiency of the antenna. Therefore, in the miniaturization design of the antenna 100 according to the embodiment of the present invention, the length of the first low-frequency connection section 31 can be adjusted, thereby changing the inductance value of the antenna 100. For example, the length of the low-frequency radiation unit 30 is reduced to reduce the antenna 100. In order to avoid the problem of reduced radiation efficiency, the length of the first low-frequency connection section 31 can be appropriately increased, thereby increasing the inductance of the antenna, so that after the length of the low-frequency radiating unit 30 is reduced, the impedance characteristic of the low-frequency radiating unit 30 can be close to Pure resistance, which can generate resonance, and the radiation efficiency will not be reduced.

The inductor 33 is any one of a serpentine bending structure, a spiral bending structure, and a wavy bending structure. In other words, the inductor 33 can be a serpentine bending structure, a spiral bending structure, or a wave-shaped bending structure, which is not limited here. Taking the serpentine bending structure of the inductor 33 shown in FIG. 1 as an example, the serpentine bending structure of the inductor 33 increases the path of the current flowing into the inductor 33, and accordingly can increase the effective electrical length of the low-frequency radiation unit 30 and reduce The resonance frequency of the low-frequency radiation unit 30 is small, so that the size of the low-frequency radiation unit 30 can be reduced. The number of bending of the inductor 33 is adjustable. Specifically, the number of bending of the inductor 33 can be determined according to the frequency band to be covered by the low-frequency radiating unit 30 and the specific equipment to which the antenna 100 is applied. For example, when the antenna 100 is used in a device that requires relatively low miniaturization of the antenna 100, the number of bends of the inductor 33 can be appropriately reduced; for another example, when the antenna 100 is applied to the antenna 100, the miniaturization demand of the antenna 100 is relatively high. When the frequency band corresponding to the low-frequency radiation unit 30 is low, at this time, the number of bending of the inductor 33 can be appropriately increased.

The width of the second low-frequency connection section 35 gradually widens from the start end A connected to the inductor 33 to the end B of the second low-frequency connection section 35. Specifically, the width of the second low-frequency connection section 35 may gradually change exponentially. The width of the second low-frequency connection section 35 gradually widens. On the one hand, the terminal inductance of the low-frequency radiating unit 30 is increased, and the path of the current flowing into the second low-frequency connection section 35 is increased, and the effective electrical length of the low-frequency radiating unit 30 is correspondingly increased. Therefore, the size of the low-frequency radiation unit 30 is reduced; on the other hand, when the width of the second low-frequency connection section 35 gradually changes exponentially, different parts of the low-frequency radiation unit 30 emit or receive electromagnetic waves of different frequencies. The ratio of the wavelength of the different frequency signals to the actual low-frequency radiating unit 30 is constant. Therefore, the width of the low-frequency radiating unit 30 gradually changes exponentially to cover more frequencies, and the bandwidth of the low-frequency radiating unit 30 can be improved.

1 again, the distance between the second high-frequency connecting sections 213 of the two high-frequency radiation parts 21 of the same high-frequency radiation unit 20 is equal to the width of the end of the second low-frequency connecting section 35. In this way, it can be ensured that the opening at the end of the second low-frequency connection section 35 is sufficiently wide, and at the same time, the longitudinal size of the antenna 100 is not increased.

Please refer to Figure 1 again, the connection between the feed point 11 and the ground point 13 has a center line, the two high-frequency radiation units 20 are symmetrically arranged about the center line, and the two low-frequency radiating units are arranged symmetrically about the center line on page 30. In this way, the antenna 100 has the largest opening angle. At this time, the current flows through the high-frequency radiation unit 20 and the low-frequency radiation unit 30 on the side of the ground point 13 (the right side shown in FIG. 1) and the current flows through The flow directions of the high-frequency radiation unit 20 and the low-frequency radiation unit 30 on the side of the feeding point 11 are the same. The radiating unit 20 and the low-frequency radiating unit 30 form a second radiating part. The induced electromotive force generated by the first radiating part and the second radiating part has the same direction, and the induced electromotive force in the same direction is superimposed, so that the antenna 100 has better directivity and better radiation performance. .

The length of the antenna 100 in the embodiment of the present invention can reach 0.28λ, that is, the distance between the ends of the two low-frequency radiation units 30 is 0.28λ. Among them, λ is the wavelength of the electromagnetic wave radiated by the low-frequency radiation unit 30. It is understandable that the length of the antenna without the miniaturization design is usually 0.5 compared with the antenna without the miniaturization design, that is, the antenna without the inductance 33 loaded and the width of the low-frequency radiation unit 30 is not gradually widened. λ, while the length of the antenna 100 in the embodiment of the present invention is shortened to 0.28λ, the size of the antenna 100 is significantly reduced.

In the antenna 100 of the embodiment of the present invention, the frequency band of the electromagnetic wave radiated by the high-frequency radiation unit 20 and the frequency band of the electromagnetic wave radiated by the low-frequency radiation unit 30 can be adjusted according to the actual requirements of the specific equipment to which the antenna 100 is applied. For example, when the antenna 100 is applied to UAV 1000 (shown in Figure 6), unmanned vehicles, smart robots and other devices, these devices usually use the free 2.4GHz and 5.8GHz frequency bands for communication. At this time, the low-frequency radiation unit The frequency band of the electromagnetic wave radiated by 30 may be 2.400 GHz to 2.4835 GHz, and the frequency band of the electromagnetic wave radiated by the high-frequency radiation unit 20 may be 5.725 GHz to 5.850 GHz. If the antenna 100 is applied to a device that uses mobile network communications (2G, 3G, 4G, 5G, etc.) to communicate, for example, a device that uses the antenna 100 uses 2G (GSM900) and 4G (FDD-LTE) for communication, then low-frequency radiation The frequency band of the electromagnetic wave radiated by the unit 30 may be 909 MHz to 960 MHz, and the frequency band of the electromagnetic wave radiated by the high-frequency radiation unit 20 may be 1755 MHz to 1860 MHz.

Please refer to FIG. 2. FIG. 2 is an impedance diagram of the antenna 100 according to an embodiment of the present invention. The horizontal axis of the impedance diagram represents the radiation frequency of the antenna 100, and the vertical axis represents the impedance value of the antenna 100. FIG. 2 is an impedance diagram obtained by taking an example that the frequency band of electromagnetic waves radiated by the low-frequency radiation unit 30 is 2.400 GHz to 2.4835 GHz, and the frequency band of electromagnetic waves radiated by the high-frequency radiation unit 20 is 5.725 GHz to 5.850 GHz. It can be seen from Figure 2 that in the 2.4G frequency band, the resistance value of the low-frequency radiation unit 30 is 37.6272 ohms (Ω), and the reactance value is -0.9900Ω, which matches the ideal impedance value (that is, the resistance is 50Ω and the reactance is 0Ω) The similarity indicates that the impedance matching between the low-frequency radiating unit 30 of the antenna 100 and the feeder is better, and the energy fed into the low-frequency radiating unit 30 by the feeder can be effectively absorbed and radiated by the low-frequency radiating unit 30. In the 5.8G frequency band, the resistance value of the high-frequency radiation unit 20 is 65.9729Ω, and the reactance value is -16.4965Ω, which is similar to the ideal impedance matching value (that is, the resistance is 50Ω and the reactance is 0Ω). The impedance matching between the high-frequency radiation unit 20 and the feeder is better, and the energy fed into the high-frequency radiation unit 20 by the feeder can be effectively absorbed and radiated by the high-frequency radiation unit 20.

Please refer to FIG. 3, which is a standing wave ratio diagram of the antenna 100 according to an embodiment of the present invention. The horizontal axis of the standing wave ratio diagram represents the radiation frequency of the antenna 100, and the vertical axis represents the standing wave ratio of the antenna 100. Fig. 3 is a standing wave ratio diagram obtained by taking an example that the frequency band of electromagnetic waves radiated by the low-frequency radiation unit 30 is 2.400 GHz to 2.4835 GHz, and the frequency band of electromagnetic waves radiated by the high-frequency radiation unit 20 is 5.725 GHz to 5.850 GHz. It can be seen from Figure 3 that in the 2.4G frequency band, the standing wave ratio of the low-frequency radiation unit 30 is less than 2, and in the 5.8G frequency band, the standing wave ratio of the high-frequency radiation unit 20 is also less than 2, which shows that the low-frequency radiation of the antenna 100 The impedance matching between the unit 30 and the feeder is better, and the energy fed into the low-frequency radiating unit 30 by the feeder is less reflected back to the feeder. Similarly, the impedance matching between the high-frequency radiating unit 20 of the antenna 100 and the feeder is also better. Preferably, the energy fed into the high-frequency radiating unit 20 by the feeder is reflected back to the feeder less, which satisfies the requirement of the antenna 100 for the standing wave ratio.

Please refer to FIG. 4. FIG. 4 is a pattern of the low-frequency radiation unit 30 of the antenna 100 according to an embodiment of the present invention. The solid line is the horizontal pattern, and the dashed line is the elevation pattern. It can be seen from FIG. 4 that the low-frequency radiation unit 30 of the antenna 100 has better omnidirectionality. Therefore, the antenna 100 can be used in devices that require high antenna omnidirectionality, such as unmanned aerial vehicles 1000 (shown in FIG. 6), unmanned vehicles and other non-fixed point communications.

Please refer to FIG. 5. FIG. 5 is a pattern of the high-frequency radiation unit 20 of the antenna 100 according to an embodiment of the present invention. The solid line is the horizontal pattern, and the dashed line is the elevation pattern. It can be seen from FIG. 5 that the omnidirectionality of the high-frequency radiation unit 20 of the antenna 100 is also better. The antenna 100 can be used in devices that require high antenna omnidirectionality, such as unmanned aerial vehicle 1000 (shown in FIG. 6), unmanned vehicles and other non-fixed point communication.

In summary, the antenna 100 of the embodiment of the present invention adds an inductor 33 in the low-frequency radiation unit 30, and designs the width of the low-frequency radiation unit 30 into a form of gradual width, so that the antenna 100 can be miniaturized and the bandwidth of the antenna 100 can be increased. , Improve the performance of the antenna 100.

Of course, in some embodiments, if the device to which the antenna 100 is applied does not have high requirements for the omnidirectionality of the antenna, at this time, the two high-frequency radiation units 20 may not be symmetrically arranged about the center line, and the two low-frequency radiation units 30 are also It can be set symmetrically about the center line. In other words, the opening angle between the first radiating part and the second radiating part may be less than 180 degrees. At this time, the antenna 100 forms a directional antenna, and the directional antenna 100 has a higher gain.

Please refer to FIG. 6, the present invention also provides an unmanned aerial vehicle 1000. The drone 1000 includes the antenna 100 and the drone body 200 of any one of the above embodiments. The antenna 100 is installed on the drone body 200. In some embodiments, the drone body may include a tripod (or landing gear), and the antenna 100 may be provided in the tripod.

In this way, since the antenna 200 is miniaturized, it can be integrated in the UAV 1000 without occupying much space of the UAV 1000, which is further conducive to the miniaturization design of the UAV 1000. In addition, the antenna 100 covers a wider frequency band and has better omnidirectionality, which can ensure the stability of communication under the non-fixed communication form of the UAV 1000.

In the description of this specification, reference is made to the terms "certain embodiments, "one embodiment, "some embodiments, "exemplary embodiments, "examples, "specific examples, or "some examples. The description means that the specific feature, structure, material, or characteristic described in combination with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above-mentioned terms does not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics can be combined in an appropriate manner in any one or more embodiments or examples.

In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, "plurality" means at least two, such as two and three, unless otherwise specifically defined.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above-mentioned embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can comment on the above-mentioned embodiments within the scope of the present invention. The embodiments undergo changes, modifications, substitutions and modifications, and the scope of the present invention is defined by the claims and their equivalents.