Magnetoelectric dipole antenna based on low profile

Abstract

The utility model discloses a magnetoelectric dipole antenna based on a low profile, which is characterized in that a connector inner core is fixedly arranged on a reflecting plate, and the connector inner core is connected with a feed structure; the feed structure comprises a first feed strip and a second feed strip, and the second feed strip comprises a first strip, a second strip, a third strip and a fourth strip; a first magnetic dipole, a second magnetic dipole, a third magnetic dipole and a fourth magnetic dipole are fixedly arranged on the reflecting plate, the first magnetic dipole is connected with the first electric dipole, the second magnetic dipole is connected with the second electric dipole, the third magnetic dipole is connected with the third electric dipole, and the fourth magnetic dipole is connected with the fourth electric dipole. The low-profile design enables the antenna to be more compact and light, the application range of the antenna is widened, the overall size and weight of equipment are reduced, the stability of the antenna is enhanced, the influence of wind resistance and mechanical vibration on the antenna is reduced, and therefore the reliability of the antenna is improved, and the service life of the antenna is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to magnetoelectric dipole technical field especially relates to a kind of based on low profile magnetoelectric dipole antenna. BACKGROUND

[0002] Now 5G mobile communication has from the beginning theory part to now large-scale commercial practice, in the process of the rapid development of mobile communication technology update, as one of the key devices in communication system, base station antenna is also constantly innovated. In order to meet the coverage of base station, base station antenna evolves from the beginning omnidirectional antenna to directional antenna, and in order to suppress multipath fading, improve channel capacity, the antenna is replaced from the original single polarization to dual polarization, and the original single-frequency narrowband 1G antenna also evolves into complex multi-band wideband antenna, the development of 5G mobile communication technology puts forward more requirements for the communication signal transmission, which includes high quality, high speed and the like. As an important part of communication system, base station antenna still faces the challenges of large antenna size, difficulty in increasing communication capacity, saving installation space and saving construction cost. Now, base station antenna needs to have the characteristics of wideband, small size and high gain, to reduce signal attenuation and ensure communication quality. Miniaturized base station antenna has attracted widespread attention due to its small size, reduced installation space and saved installation cost, and magnetoelectric dipole antenna is widely used in base station antenna design due to its excellent radiation characteristics and wideband characteristics, and miniaturized magnetoelectric dipole antenna has also attracted more and more attention. The current low profile magnetoelectric dipole method can be summarized as follows: folding magnetic dipole, loading super material, loading frequency selective surface structure and the like.

[0003] As China patent publication No. CN112117534B discloses a kind of high isolation degree based on PCB bipolar magnetoelectric dipole antenna and optimization method, including, dielectric substrate, for providing the electrical connection between elements, it includes base hole and floor, base hole is embedded in the center position of dielectric substrate and couples electromagnetic wave signal into patch unit;Patch unit is placed on the upper surface of dielectric substrate, for building electric dipole, it includes radiating patch and cross piece, radiating patch has four and forms quarter wavelength aperture equivalent to magnetic dipole with cross piece;Feed unit is set on the upper surface of dielectric substrate and crosses patch unit, and presents fork-shaped microstrip structure. The feed structure in the utility model adopts fork-shaped microstrip feed form and H-shaped aperture coupling, which has higher resonant impedance, good cross polarization performance and isolation degree.

[0004] In the prior art, the magnetic dipole is generally bent, but the bending of the magnetic dipole will cause the impedance matching and radiation performance of the antenna to deteriorate. How to reduce the height of the antenna while ensuring the performance of the antenna, through research and analysis of the structure of the traditional magnetic electric dipole antenna, the magnetic dipole is bent, the height of the entire antenna is reduced, and the original feed line structure is bent to improve the impedance matching of the antenna. SUMMARY

[0005] The application provides a low-profile magnetic electric dipole antenna and an optimization method. The low-profile design makes the antenna more compact and portable, easy to integrate into various devices, improves the application range of the antenna, reduces the overall size and weight of the device, and enhances the stability of the antenna. Since the height of the antenna is reduced, its resistance to wind and mechanical vibration is also reduced, thereby improving the reliability and service life of the antenna.

[0006] The application provides a low-profile magnetic electric dipole antenna, which includes:

[0007] The reflector is used for reflecting electromagnetic waves, and a connector inner core is fixedly arranged on the reflector. The connector inner core is connected with a feed structure, and is used for supporting the feed structure. The feed structure includes a first feed strip and a second feed strip. The second feed strip includes a first strip, a second strip, a third strip, and a fourth strip. A first magnetic dipole, a second magnetic dipole, a third magnetic dipole, and a fourth magnetic dipole are fixedly arranged on the reflector. The first magnetic dipole is connected with a first electric dipole, the second magnetic dipole is connected with a second electric dipole, the third magnetic dipole is connected with a third electric dipole, and the fourth magnetic dipole is connected with a fourth electric dipole.

[0008] Preferably, the first feed strip and the second feed strip are orthogonally arranged, and the height of the first feed strip is greater than the height of the second feed strip.

[0009] Preferably, the first strip is parallel to the vertical arm of the magnetic dipole, and the first strip is used for guiding energy to the magnetic dipole.

[0010] Preferably, the second strip is an L-shaped structure composed of two metal strips with different lengths, and the second strip is used for coupling energy to the bent magnetic dipole.

[0011] Preferably, the third strip is horizontally arranged and in an inductive state, and the third strip is used for coupling the transmitted energy to the electric dipole.

[0012] Preferably, the fourth strip is an L-shaped structure and in a capacitive state, and the fourth strip is used for offsetting the inductive part introduced by the third strip (14).

[0013] Preferably, the first strip, the second strip, the third magnetic dipole and the fourth magnetic dipole constitute a transmission line.

[0014] The application also provides an optimization method based on a low-profile magneto-electric dipole antenna. The specific method for optimizing the magneto-electric dipole antenna is as follows:

[0015] S101, obtaining a variation range of impedance according to an electromagnetic simulation tool;

[0016] S102, matching an impedance value based on a use scenario of the antenna, and designing a matching network according to the matched impedance value;

[0017] S103, simulating the designed matching network;

[0018] S104, adjusting parameters of the matching network according to a simulation result.

[0019] Preferably, based on the designed matching network, the step of constructing an optimization model is as follows:

[0020] S201, setting an adjustment range of parameters based on the parameters of the matching network;

[0021] S202, selecting an optimization algorithm based on the adjustment range of parameters, and constructing an optimization model;

[0022] S203, collecting historical data, and selecting candidate data from the collected historical data;

[0023] S204, comparing the selected candidate data with data calculated by the optimization model, and obtaining fitness of the optimization model.

[0024] Preferably, the candidate data is input into the optimization model, the optimization model calculates a performance prediction value corresponding to the parameters according to an embedded algorithm, compares the calculated performance prediction value with an actual performance value in the candidate data, calculates an error between the performance prediction value and the candidate value, and takes an inverse of the calculated error.

[0025] The one or more technical solutions provided in the application have at least the following technical effects or advantages: the low-profile design makes the antenna more compact and light, is easy to integrate into various devices, improves the application range of the antenna, reduces the overall size and weight of the device, the low-profile design enhances the stability of the antenna, since the height of the antenna is reduced, the antenna is less affected by wind resistance and mechanical vibration, thereby improving the reliability and service life of the antenna, the antenna combines the advantages of magnetic dipoles and electric dipoles, and realizes wideband radiation characteristics, which enables the antenna to maintain stable gain and radiation patterns in a wider frequency band, by optimizing the structure and size of the antenna, higher gain can be achieved, the radiation pattern of the antenna is stable and uniform, and the application requirements of outdoor directional base stations and the like can be met;

[0026] By precise impedance matching characteristic analysis and matching network design, the impedance matching effect of the antenna feed port is improved, the reflection and loss of signals in the transmission process are reduced, energy can be more efficiently transmitted from the transmission line to the antenna radiation part, and the radiation efficiency of the antenna is improved; the overall performance of the antenna is comprehensively simulated, evaluated and tested, so that the key performance indicators such as gain, beam width, radiation pattern and cross-polarization ratio of the antenna meet the design requirements, and through optimization and adjustment, the antenna shows stable gain, narrow and stable beam width, clear radiation pattern and high cross-polarization ratio in the target frequency band, thereby improving the communication quality. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a structure schematic view of the low-profile magnetic electric dipole antenna of the embodiment of the utility model;

[0028] Figure 2 It is a side view of the magnetic electric dipole antenna of the embodiment of the utility model;

[0029] Figure 3 It is a structure schematic view of the antenna feed of the embodiment of the utility model;

[0030] Figure 4 It is a graph of return loss of each port of the antenna of the embodiment of the utility model;

[0031] Figure 5 It is a graph of antenna gain and beam width changing with frequency of the embodiment of the utility model;

[0032] Figure 6a , Figure 6b , Figure 6c It is a horizontal plane radiation pattern of the antenna at different frequency points of the embodiment of the utility model;

[0033] Figure 7 It is a flow schematic view of the optimization method of the low-profile magnetic electric dipole antenna of the embodiment of the utility model;

[0034] Figure 8 For the matching network based on the design of the embodiment of the utility model, the flow diagram of constructing the optimization model is shown.

[0035] In the figure: 1, second electric dipole; 2, first electric dipole; 3, fourth electric dipole; 4, third electric dipole; 5, first magnetic dipole; 6, second magnetic dipole; 7, third magnetic dipole; 8, fourth magnetic dipole; 9, first feed strip; 10, second feed strip; 11, reflector plate; 12, first strip; 13, second strip; 14, third strip; 15, fourth strip. DETAILED DESCRIPTION

[0036] In order to facilitate understanding of the utility model, the application will be described more comprehensively below with reference to the relevant drawings.

[0037] Embodiment one: Figure 1 It is a kind of based on low profile magnetoelectric dipole antenna of the utility model embodiment, such as Figure 2 And Figure 3As shown, it comprises: a reflecting plate 11 made of a metal aluminum plate with conductivity and reflectivity, the reflecting plate 11 is used to reflect electromagnetic waves, enhance the directivity and gain of the antenna, and the SMA coaxial connector inner core is fixedly arranged on the reflecting plate 11, the SMA coaxial connector inner core is connected with the feed structure, and the SMA coaxial connector inner core is used to support the feed structure; the feed structure comprises a first feed strip 9 and a second feed strip 10, the first feed strip 9 and the second feed strip 10 are orthogonally arranged, the height of the first feed strip 9 is greater than the height of the second feed strip 10, so as to avoid intersection and ensure efficient transmission of energy; the second feed strip 10 comprises a first strip 12, a second strip 13, a third strip 14 and a fourth strip 15; the first strip 12 is isosceles trapezoidal, the isosceles trapezoidal has two equal legs and an upper base and a lower base, the width of the upper base is less than that of the lower base, the upper base is connected with the input end of the feed structure, and the lower base corresponds to the vertical arm of the magnetic dipole; the design of the trapezoidal shape makes the first strip 12 gradually change in width, so that the transmitted electromagnetic wave energy can be more uniformly distributed, and the energy can be avoided from being excessively concentrated or missing in a certain area; the second strip 13 is L-shaped structure, the second strip 13 is composed of two metal strips with different lengths, the two metal strips are perpendicular to each other and connected together to form an L-shaped structure, one of the metal strips is longer and connected with the feed structure, responsible for receiving and transmitting electromagnetic wave energy, and the other metal strip is shorter and corresponds to the bent magnetic dipole, responsible for efficiently coupling the energy to the magnetic dipole; the design of the L-shaped structure of the second strip 13 makes the energy be able to be bent during transmission, so that the energy can be more efficiently coupled to the bent magnetic dipole, the coupling mode reduces the loss of energy, and the radiation efficiency of the antenna is improved; the third strip 14 is horizontally arranged and in inductive state, the inductive characteristic makes the third strip 14 have the characteristics of delay and energy storage in response to electromagnetic waves, at the same time, the inductive characteristic makes the antenna be able to form resonance in a specific frequency band, so as to enhance the radiation efficiency and directivity of the antenna; the third strip 14 is used to couple the transmitted energy to the electric dipole; the fourth strip 15 is L-shaped structure and in capacitive state, when the inductive component is introduced into the third strip 14, the impedance of the antenna in a specific frequency band will change, which affects the radiation efficiency and signal receiving ability of the antenna; the capacitive state of the fourth strip 15 can produce an electromagnetic effect opposite to the inductive component, thereby effectively offsetting or balancing the inductive effect, the mutual offsetting of the capacitance and the inductance reaches the state of impedance matching, so that the antenna maintains stable impedance characteristics in a wider frequency band, and the overall performance of the antenna, including the radiation efficiency, signal receiving stability and directivity, is improved.

[0038] As Figure 4 , Figure 5 and Figure 6a , Figure 6b , Figure 6cAs shown, the first magnetic dipole 5, the second magnetic dipole 6, the third magnetic dipole 7 and the fourth magnetic dipole 8 are fixedly arranged on the reflecting plate 11, the first magnetic dipole 5 is connected with the first electric dipole 2, the second magnetic dipole 6 is connected with the second electric dipole 1, the third magnetic dipole 7 is connected with the third electric dipole 4, and the fourth magnetic dipole 8 is connected with the fourth electric dipole 3, the first electric dipole 2, the second electric dipole 1, the third electric dipole 4 and the fourth electric dipole 3 are horizontally placed, and the four electric dipoles constitute the electric field radiation part of the antenna; the first magnetic dipole 5, the second magnetic dipole 6, the third magnetic dipole 7 and the fourth magnetic dipole 8 are all bent, the feeding structure is also bent at the same time of bending the magnetic dipoles, the impedance matching of the antenna is improved, the profile is reduced to 0.16λL, the impedance bandwidth of the first port of the antenna is 31% (3.12-4.28GHz, |S11|<-15dB), the impedance bandwidth of the second port is 29.2% (3.28-4.40GHz, |S22|<-15dB), the port isolation is higher than 18dB, the gain is stable at 7.56-9.94dBi in the working frequency band, the H-plane beam width is stable between 65±7°, the magnetic dipoles and the electric dipoles are connected and jointly constitute the radiation unit of the antenna, when the electromagnetic wave signal is transmitted to the magnetic dipoles through the feeding structure, they will respond quickly and produce strong magnetic field radiation, unlike the electric dipoles, the magnetic dipoles mainly radiate electromagnetic waves through the magnetic field, thereby forming a complement with the electric dipoles to realize the omnidirectional radiation of the antenna.

[0039] The technical solutions in the embodiments of the application have at least the following technical effects or advantages: the low-profile design makes the antenna more compact and light, is easy to integrate into various devices, improves the application range of the antenna, reduces the overall size and weight of the device, the low-profile design enhances the stability of the antenna, as the height of the antenna is reduced, the influence of wind resistance and mechanical vibration on the antenna is also reduced, thereby improving the reliability and service life of the antenna, the antenna combines the advantages of magnetic dipoles and electric dipoles to realize the wideband radiation characteristics, which enables the antenna to maintain stable gain and radiation pattern in a wider frequency band, by optimizing the structure and size of the antenna, a higher gain can be achieved, the radiation pattern of the antenna is stable and uniform, and can meet the application requirements of outdoor directional base stations and the like.

[0040] Embodiment two: based on embodiment one, the magnetic-electric dipole antenna is optimized to improve the impedance matching effect of the antenna.

[0041] As shown in Figure 7 The specific method for optimizing the magnetic-electric dipole antenna is as follows:

[0042] S101, obtaining the change range of impedance according to an electromagnetic simulation tool;

[0043] Specifically, the electromagnetic simulation software Ansys is used to model the existing antenna feed structure in three dimensions. After modeling, the simulation parameters are set, the simulation program is run, and the key data such as the propagation path of electromagnetic waves in the antenna structure and the reflection coefficient are calculated according to the set parameters and model. The data is exported to an external file, and the impedance variation curve is drawn using the data visualization tool MATLAB. The impedance variation curve usually contains two lines, one representing the real part R of the impedance and the other representing the imaginary part X of the impedance, both of which change with frequency. In the 5G N78 frequency band, the two lines fluctuate accordingly as the frequency increases from 3.3 GHz to 3.8 GHz.

[0044] S102, matching the impedance value based on the use scenario of the antenna, and designing a matching network according to the matched impedance value;

[0045] Specifically, the matching method is selected as microstrip line matching, which can provide stable impedance transformation. The parameters of microstrip line matching are calculated, including length, width and position. The length of the microstrip line is related to the wavelength of the electromagnetic wave, which determines the phase change of the electromagnetic wave on the microstrip line. By accurately calculating the length, the required phase difference is obtained when the electromagnetic wave is transmitted on the microstrip line, thereby realizing impedance matching. The width of the microstrip line affects its characteristic impedance and affects the impedance matching effect. The width is calculated using simulation software. The microstrip line is closely connected with the feed structure of the antenna, and the position is accurate to reduce the loss and reflection in the energy transmission process.

[0046] S103, simulating the designed matching network;

[0047] Further, the designed matching network is integrated into the antenna model, and the integrated antenna model is simulated to collect the return loss of the port, i.e. the S11 parameter. The return loss is a curve that changes with frequency, representing the return loss value of the antenna feed port at different frequencies. The preset threshold of return loss is -15 dB. Within the entire operating frequency band, if the return loss is less than -15 dB, it means that the impedance of the antenna feed port and the characteristic impedance of the transmission line are matched, and the energy can be efficiently transmitted from the transmission line to the antenna radiation part. Otherwise, the matching is not achieved.

[0048] S104, adjusting the parameters of the matching network according to the simulation results.

[0049] Specifically, when the simulation results show that the matching effect is not ideal, the length and width of the microstrip line are adjusted, increasing the length of the microstrip line will reduce its impedance, and reducing the length may increase the impedance, increasing the width of the microstrip line will reduce its impedance, and reducing the width may increase the impedance, after adjusting the parameters, re-run the simulation, and observe the change of return loss, if the change meets the expectation, do not continue to adjust, if the change is not large or does not meet the expectation, other parameters need to be re-analyzed and adjusted, through multiple simulations and adjustments, gradually approach the optimal solution.

[0050] The technical solutions in the embodiments of the present application have at least the following technical effects or advantages: through accurate impedance matching characteristic analysis and matching network design, the impedance matching effect of the antenna feed port is improved, the reflection and loss of signals in the transmission process are reduced, so that energy can be more efficiently transmitted from the transmission line to the antenna radiation part, and the radiation efficiency of the antenna is improved; the overall performance of the antenna is comprehensively simulated, evaluated and tested, so that the key performance indicators such as gain, beam width, radiation pattern and cross-polarization ratio of the antenna all meet the design requirements, through optimization and adjustment, the antenna shows stable gain, narrow and stable beam width, clear radiation pattern and high cross-polarization ratio in the target frequency band, and the communication quality is improved.

[0051] Embodiment three: based on the parameters in the matching network in embodiment two, set the range of the parameters, the adjustment of the range of the parameters is limited by the size of the antenna board, in this embodiment, the range of the parameters is set based on embodiment two, and an optimization model is created according to the range of the parameters.

[0052] As shown in Figure 8 , based on the designed matching network, the steps of constructing the optimization model are:

[0053] S201, based on the parameters of the matching network, set the adjustment range of the parameters;

[0054] Specifically, based on the adjustment of the length and width of the microstrip line in step S104, according to the size of the antenna board and the working frequency, the adjustment range of the length of the microstrip line is 5mm to 50mm, according to the size of the antenna board and the impedance requirement, the adjustment range of the width of the microstrip line is 0.5mm to 5mm, according to the adjustment range of the parameters, set the discrete points, for the length of the microstrip line, set a discrete point every 1mm, for each parameter, generate a list containing all discrete points, for the length of the microstrip line, generate a discrete point list from 5mm to 50mm with a step of 1mm.

[0055] S202, select an optimization algorithm based on the parameter adjustment range, and construct an optimization model;

[0056] Further, the length and width of the microstrip line are used as optimization variables, and are expressed by mathematical symbols, the impedance matching characteristic (return loss) and performance index (gain, beam width) of the antenna are used as optimization objectives, and are expressed by constraint conditions, the optimization model between the parameters and the optimization objectives is established according to the above data, and the optimization variables, the optimization objectives and the constraint conditions are combined to form a complete optimization problem.

[0057] S203, collecting historical data, and selecting candidate data in the collected historical data;

[0058] Specifically, historical data is collected, data related to network optimization is identified in the collected historical data, the identified data is integrated into a data set, candidate data is selected from the data set in a random sampling manner according to the requirements of the optimization target and the characteristics of the data, the candidate data is verified, and the candidate data that passes the verification is integrated into a candidate data set.

[0059] S204, comparing the selected candidate data with the data calculated by the optimization model to obtain the fitness of the optimization model.

[0060] Further, the candidate data is input into the optimization model, the optimization model calculates the performance prediction value corresponding to the parameters according to the built-in algorithm, compares the calculated performance prediction value with the actual performance value in the candidate data, calculates the error, takes the reciprocal of the calculated error, and the higher the value of the reciprocal of the error, the stronger the prediction ability of the optimization model and the better the fitness.

[0061] The technical solutions in the embodiments of the application have at least the following technical effects or advantages: the parameter adjustment range and the discrete point setting limit the search space, reduce invalid calculations, improve optimization efficiency, comparison with the actual performance value can timely discover and correct errors in the model, improve the accuracy of the model, fitness evaluation provides a clear guidance direction for model improvement, and application of the optimization model enables design parameters to more accurately meet the requirements of impedance matching characteristics and performance indexes.

[0062] The above only describes preferred embodiments of the present application and is not used to limit the present application, and for those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A low profile magneto-electric dipole antenna, comprising: The application relates to a connector for transmitting electromagnetic wave, which comprises the following parts: A connector inner core is fixedly arranged on a reflecting plate (11) used for reflecting electromagnetic wave, the connector inner core is connected with a feeding structure, and the connector inner core is used for supporting the feeding structure; The feeding structure comprises a first feeding strip (9) and a second feeding strip (10), the second feeding strip (10) comprises a first strip (12), a second strip (13), a third strip (14) and a fourth strip (15); The reflecting plate (11) is fixedly provided with a first magnetic dipole (5), a second magnetic dipole (6), a third magnetic dipole (7) and a fourth magnetic dipole (8), the first magnetic dipole (5) is connected with a first electric dipole (2), the second magnetic dipole (6) is connected with a second electric dipole (1), the third magnetic dipole (7) is connected with a third electric dipole (4), and the fourth magnetic dipole (8) is connected with a fourth electric dipole (3).

2. A low profile magneto-dipole antenna according to claim 1, wherein, The first feeding strip (9) and the second feeding strip (10) are orthogonally arranged, the height of the first feeding strip (9) is greater than that of the second feeding strip (10).

3. A low profile magneto-dipole antenna according to claim 1, wherein, The first strip (12) is parallel to the vertical arm of the magnetic dipole, and the first strip (12) is used for guiding energy to the magnetic dipole.

4. The low profile magneto-dipole antenna of claim 1, wherein: The second strip (13) is an L-shaped structure, the second strip (13) is composed of two metal strips with different lengths, and the second strip (13) is used for coupling energy to the bent magnetic dipole.

5. The low profile magneto-dipole antenna of claim 1, wherein, The third strip (14) is horizontally arranged and is in an inductive state, and the third strip (14) is used for coupling the transmitted energy to the electric dipole.

6. A low profile magneto-dipole antenna according to claim 1, wherein, The fourth strip (15) is an L-shaped structure and is in a capacitive state, and the fourth strip (15) is used for offsetting the inductive part introduced by the third strip (14).

7. The low profile magneto-dipole antenna of claim 3, wherein: The first strip (12), the second strip (13), the third magnetic dipole (7) and the fourth magnetic dipole (8) constitute a transmission line.

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