Dual-polarized antenna device based on a hybrid structure of a magnetoelectric dipole and a printed monopole

Abstract

The application relates to the technical field of antenna manufacturing, in particular to a mixed structure dual-polarized antenna device based on a magnetic electric dipole and a printed vibrator, which can form orthogonal radiation far fields, realize dual-polarization function, has a simple structure and is easy to process and assemble, and the device is characterized in that: the device comprises horizontal and vertical two polarization ports which are respectively composed of a magnetic electric dipole antenna radiator and a printed vibrator antenna radiator; the magnetic electric dipole antenna radiator adopts a printed circuit board for bottom feeding, and the feeding mode is slot coupling; the printed circuit of the printed vibrator antenna radiator is located in the slot of the magnetic electric dipole antenna radiator, the field polarization direction of the printed vibrator antenna radiator is orthogonal to the polarization direction of the magnetic electric dipole, and the two work cooperatively; the magnetic electric dipole antenna radiator is fed in a microstrip line edge feeding mode, and the output port is located at the bottom of the antenna; the printed vibrator antenna radiator introduces a double-wire bending mode and is fed in a bottom feeding mode.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of antenna manufacturing, in particular to a mixed-structure dual-polarized antenna device based on a magnetic-electric dipole and a printed vibrator, which can form orthogonal radiation far fields, realize dual-polarization functions, has a simple structure and is easy to process and assemble. BACKGROUND

[0002] With the rapid development of electronic information technology, the polarization information of electromagnetic waves is paid more and more attention and obtains a large amount of research and application. The introduction of polarization information can improve the working performance of a radar and a communication system, and in particular in the field of electronic warfare, the use of polarization characteristics provides an effective technical means for electronic countermeasures. In a polarization electronic system, the acquisition of polarization information is realized through a polarization-sensitive antenna sensor device, therefore, the design and implementation of the polarization-sensitive antenna become a key technology of the polarization electronic system. A dual-polarized antenna is a commonly used polarization-sensitive antenna form, the dual-polarized antenna usually contains two polarization ports, the two polarization ports radiate and receive electromagnetic component signals of orthogonal polarization, and can realize the function of polarization diversity. In a communication system, the dual-polarized antenna is an effective scheme for increasing channel capacity and resisting multipath fading effect in the wireless communication process, and is widely applied. In a radar system, the dual-polarized antenna can realize the full polarization radiation and reception of electromagnetic waves, effectively improves the detection distance and the anti-electromagnetic interference ability of the radar, and the dual-polarized antenna is a physical basis for polarization signal processing of the polarization radar.

[0003] At present, there are many forms of dual-polarized antennas, for example, a dual-polarized microstrip patch antenna, a dual-polarized slot antenna, a dual-polarized dipole antenna and the like. The patch antenna has the advantages of low profile, low processing cost, light weight and easy batch production, but the patch antenna has the disadvantage of narrow working bandwidth; in recent years, researchers design various feed structures to stimulate the antenna to realize the wideband performance from the feed structure of the antenna. The dual-polarized slot antenna is a kind of antenna that relies on a slot to stimulate electromagnetic energy to radiate to the free space, and is focused on because it is easy to realize the wideband characteristic. The dual-polarized dipole antenna has a simple structure, is easy to expand the impedance bandwidth and has a stable pattern, therefore, the dual-polarized dipole antenna is concerned by antenna engineers and is applied to a base station communication system. SUMMARY

[0004] The application provides a mixed-structure dual-polarized antenna device based on a magnetic-electric dipole and a printed vibrator, which can form orthogonal radiation far fields, realize dual-polarization functions, has a simple structure and is easy to process and assemble.

[0005] The application achieves the above-mentioned purposes through the following measures.

[0006] The application discloses a kind of based on the mixed structure bipolar antenna device of magnetoelectric dipole and printed vibrator, it is characterized in that, contain horizontal and vertical two polarization ports respectively by magnetoelectric dipole antenna radiator and printed vibrator antenna radiator, the magnetoelectric dipole antenna radiator adopts printed circuit board to bottom feed, feed mode is slot coupling;Printed circuit of printed vibrator antenna radiator is located in the slot of magnetoelectric dipole antenna radiator, the field polarization direction of printed vibrator antenna radiator and the polarization direction of magnetoelectric dipole are orthogonal, and they work together;

[0007] Magnetoelectric dipole antenna radiator adopts the mode of microstrip line edge feed, output port is located at the bottom of antenna;Printed vibrator antenna radiator introduces double-line bending mode, adopts the mode of bottom feed, output port is also located at the bottom of antenna;

[0008] The magnetoelectric dipole antenna radiator uses a Γ type feed line strip to simultaneously excite horizontal patch and vertical short-circuit patch, the horizontal patch acts as a pair of electric dipoles, and the vertical short-circuit patch connected to the horizontal patch acts as a magnetic dipole and is connected to the ground plate at the same time, and the magnetoelectric dipole antenna radiator is excited by the Γ type feed line between the two vertical magnetic dipole patches;The Γ type feed line is divided into three parts: the first part is a vertical part connected to the inner core of the coaxial line below the reflecting plate at the bottom end, the vertical part and the adjacent vertical magnetic dipole patch form a microstrip transmission line with air as the dielectric medium, and the characteristic impedance is 50 ohms, so that the electrical signal is transmitted to the second part of the Γ type feed line;The second part is the horizontal part of the Γ type feed line, and the horizontal part is at the same height as the horizontal electric dipole of the antenna radiator, so that the energy is transmitted to the horizontal electric dipole and the vertical magnetic dipole through coupling, and the horizontal part is inductive;The part close to the other vertical patch is the third part of the Γ type feed line, and the third part and the vertical magnetic dipole form a transmission line with open terminal, and the third part is capacitive, and the capacitance of the third part and the inductance of the second part are offset to achieve good matching.

[0009] The E-plane of the electric dipole in the magnetoelectric dipole antenna radiator is in the shape of an "8", and the H-plane is in the shape of an "O"; the E-plane of the magnetic dipole is in the shape of an "O", and the H-plane is in the shape of an "8", and when the electric dipole and the magnetic dipole are excited by signals at the same time, the forward radiation fields of the two are in phase and superimposed, while the backward radiation fields are in opposite phase and offset, and the far-field radiation pattern in the azimuth plane is in the shape of a heart, so that the magnetoelectric dipole antenna can obtain a stable radiation pattern.

[0010] In the application, aluminum plate is used as the processing material of the magnetic dipole, and the magnetic dipole is of a rectangular structure, so the processing is simple; the electric dipole is realized by using a printed circuit structure, a vibrator shape is etched on a dielectric substrate, the dielectric substrate is placed above the magnetic dipole, and the metal pattern of the electric dipole directly contacts the metal arm of the magnetic dipole; the excitation of the magneto-electric dipole is realized by using a gap coupling mode, the metal floor is in the form of a printed circuit, the copper foil on one side of the dielectric substrate is used as a metal ground, a rectangular gap is etched on the copper foil, a microstrip line orthogonal to the gap is etched on the other side of the dielectric substrate, and the effect of electromagnetic coupling excitation is formed; in order to realize the impedance matching and the resonant state of the antenna, a fan-shaped branch is used at the end of the microstrip line of the feed, the radius of the fan-shaped branch is adjusted, the effect of impedance matching is obtained, meanwhile, the characteristic impedance of the output microstrip line is 50 ohms at the other end of the microstrip line, and a gradual line impedance transformation section is introduced between the output microstrip line and the feed microstrip line, so as to realize the impedance matching of a wide band.

[0011] In the printed vibrator antenna radiator, the rectangular printed vibrators are respectively placed on the upper and lower sides of the printed dielectric substrate; since the microstrip line is a non-balance structure, when the printed symmetrical vibrator of the balance structure is fed, a Balun structure is introduced, and a microstrip line gradual Balun is used; one end of the microstrip line printed Balun is a 50 ohm microstrip line, and the other end is a double-sided parallel double line, so that the double-sided printed symmetrical vibrator can be directly connected, a triangular transition structure is used at the center of the radiator vibrator, the vibrator centers converge to the same position, and the double-sided parallel double line is formed; in order to reduce the shielding effect of the two polarization ports, the double-sided printed double line is bent, the bottom output of the printed symmetrical vibrator port is realized, and meanwhile, a reasonable double-sided printed double line width is used to ensure impedance matching, reduce the shielding and coupling influence of the printed symmetrical vibrator antenna on the magneto-electric dipole antenna, and ensure the electromagnetic isolation performance.

[0012] The application provides a design scheme and an antenna device of a combined dual-polarized antenna based on a magneto-electric dipole and a printed vibrator. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure Figure 1 is a structural schematic diagram of the present application, Figure 1 (a) is a perspective view, Figure 1 (b) is another angle schematic diagram.

[0014] Figure Figure 2 is a schematic diagram of the magnetic-electric dipole antenna radiator in the present application, Figure 2 (a) is a top view, Figure 2 (b) is a side view, Figure 2 (c) is a bottom view.

[0015] Figure Figure 3 is a schematic diagram of the printed vibrator antenna radiator in the present application, Figure 3 (a) is a first view schematic diagram, Figure 3 (b) is a second view schematic diagram, Figure 3 (c) is a third view schematic diagram.

[0016] Figure Figure 4 is a schematic diagram of the antenna working principle in the present application, Figure 4 (a) is a three-dimensional radiation pattern, Figure 4 (b) is a two-dimensional radiation pattern.

[0017] Figure Figure 5 is a basic model schematic diagram of the magnetic-electric dipole antenna in the present application.

[0018] Figure Figure 6 is a circuit characteristic simulation result diagram of the antenna port in the present application, Figure 6 (a) is the VSWR of port 1; Figure 6 (b) is the VSWR of port 2, Figure 6 (c) is the port isolation.

[0019] Figure Figure 7 is the radiation characteristic simulation result of port 1 of the antenna device in the embodiment at a frequency of 2.5GHz, wherein Figure 7 (a) is a three-dimensional gain pattern, Figure 7 (b) is a three-dimensional axial ratio pattern, Figure 7 (c) is a gain pattern in the xoz plane, Figure 7 (d) is an axial ratio pattern in the xoz plane, Figure 7 (e) is a gain pattern in the yoz plane, Figure 7 (f) is an axial ratio pattern in the yoz plane.

[0020] Figure Figure 8 is the radiation characteristic simulation result of port 2 of the antenna device in the embodiment at a frequency of 2.5GHz, wherein Figure 8 (a) is a three-dimensional gain pattern, Figure 8(b) is a three-dimensional axis ratio pattern. Figure 8 (c) shows the gain pattern in the xoz plane. Figure 8 (d) is the axial ratio pattern in the xoz plane. Figure 8 (e) shows the gain pattern in the yoz plane. Figure 8 (f) is the axial ratio pattern in the yoz plane.

[0021] Appendix Figure 9 Here are the gain curves of the two polarization ports as a function of frequency in the embodiment. Figure 9 (a) is port 1. Figure 9 (b) is port 2.

[0022] Appendix Figure 10 These are curves showing the change in axial ratio of the two polarization ports as a function of frequency in the embodiment. Figure 10 (a) is port 1. Figure 10 (b) is port 2.

[0023] Reference numerals in the attached figures: 1 is a magnetoelectric dipole antenna radiator, 2 is a printed dipole antenna radiator, 3 is an electric dipole arm, 4 is a magnetic dipole arm, 5 is an excitation slot, 6 is a metal ground plane, 7 is a fan-shaped tuning stub, 8 is an electromagnetic coupling section, 9 is an impedance transformation section, 10 is a printed dipole arm, 11 is a parallel two-line transmission line, and 12 is a gradient line impedance transformation section. Detailed implementation method:

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] The present application is directed to the technical requirement of antenna device in the polarization sensitive electronic system, and proposes a design scheme of combined dual-polarized antenna based on magnetoelectric dipole and printed monopole and an antenna device. The antenna device contains horizontal and vertical polarization ports, which are respectively composed of magnetoelectric dipole antenna radiator and printed monopole radiator. By using the structural characteristics of the two radiators, good isolation of the two polarization structures is realized, the distance between the two feeding positions is pulled far away, the whole antenna structure is convenient to install, there is no cross folding phenomenon of the conventional dual-polarized antenna, and the problems of electrical contact and cross assembly of the two ports are avoided. The two polarization radiators have different radiation mechanisms, and they can form orthogonal radiation far field in space to realize the function of dual polarization. The two polarization radiators can be designed independently, the parameter optimization process is simplified, and the design difficulty is reduced. The whole antenna structure is simple, low in cost, easy to process and assemble. The whole antenna is mainly processed by printed circuit technology, the mechanical processing part is simple and reliable, and is suitable for engineering application. The magnetoelectric dipole antenna radiator adopts printed circuit board to feed the antenna from the bottom, the feeding mode is slot coupling, and a wide working frequency band is realized. The electric dipole and the magnetic dipole are realized by mechanical processing, and the structure is simple and the precision is easy to control. The other polarization port is a printed monopole antenna structure, the whole radiator is in the form of printed circuit, the printed circuit is located in the feeding slot of the magnetoelectric dipole, the field polarization direction of the monopole is orthogonal to the polarization direction of the magnetoelectric dipole, and the two can work together. The magnetoelectric dipole adopts a microstrip line edge feeding mode, and the output port is located at the bottom of the antenna system. The printed monopole antenna introduces a double-line bending mode, adopts a bottom feeding mode, and the output port is also located at the bottom of the antenna system. The combined antenna model based on the magnetoelectric dipole and the printed monopole designed by the present application is shown in Figure 1 . Figure 2 It is a structure diagram of the magnetoelectric dipole antenna radiator (polarization port 1), Figure 3 It is a structure diagram of the printed monopole antenna radiator (polarization port 2). In Figure 1 , 1 is a magnetoelectric dipole antenna radiator, and 2 is a printed monopole antenna radiator

[0026] The present application designs a slot-excited magnetoelectric dipole radiator, in Figure 2 , 3 is an electric monopole arm, 4 is a magnetic monopole arm, 5 is an excitation slot, 6 is a metal floor, 7 is a fan-shaped tuning branch, 8 is an electromagnetic coupling section, and 9 is an impedance transformation section. Figure 4 It is a working principle diagram of the complementary antenna, in which Figure 4(a) gives the far-field radiation pattern of a pair of orthogonally placed electric and magnetic dipoles. The E-plane of the electric dipole is an "8" shaped pattern, and the H-plane is an "O" shaped pattern. The magnetic dipole is just the opposite of the electric dipole, and its E-plane is an "O" shaped pattern, and the H-plane is an "8" shaped pattern. When the electric and magnetic dipoles are excited simultaneously, their forward radiation fields add in phase, and their backward radiation fields cancel in phase. The far-field radiation pattern in the azimuth plane is heart-shaped. Therefore, the magneto-electric dipole antenna can obtain a stable radiation pattern. The basic magneto-electric dipole antenna model is shown in Figure 5 The antenna structure is compact, and a Γ-shaped feed line strip is used to excite the horizontal patch and the vertical short-circuit patch simultaneously. The horizontal patch of the antenna serves as a pair of electric dipoles, and the vertical short-circuit patch connected thereto serves as a magnetic dipole and is connected to the ground plane, thus forming a novel magneto-electric dipole antenna. The antenna is excited by a Γ-shaped feed line between two vertical magnetic dipole patches. The Γ-shaped feed line has three parts: the first part is a vertical part connected to the inner core of a coaxial line placed below the reflector, which forms a microstrip transmission line with the adjacent vertical magnetic dipole patch in air as the dielectric, has a characteristic impedance of 50 ohms, and can transmit electrical signals to the second part of the Γ-shaped feed line; the second part is a horizontal part of the Γ-shaped feed line, which is at the same height as the horizontal electric dipole of the antenna, and transmits energy to the horizontal electric dipole and the vertical magnetic dipole by coupling. This part is mainly inductive; the third part is close to the other vertical patch, which forms an open-circuit transmission line with the vertical magnetic dipole. This part is mainly capacitive, and the capacitance of this part and the inductance of the second part can be cancelled out by optimizing the length of this part, so as to achieve good matching. In the present application, aluminum plate is used as the processing material of the magnetic dipole. Since the magnetic dipole is of a rectangular structure, it is simple to process. The electric dipole is realized by a printed circuit structure. The vibrator-shaped pattern is etched on the dielectric substrate, the dielectric substrate is placed above the magnetic dipole, and the metal pattern of the electric dipole directly contacts the metal arm of the magnetic dipole. The excitation of the magneto-electric dipole is realized by gap coupling. The metal ground plane is in the form of a printed circuit. The copper foil on one side of the dielectric substrate is used as the metal ground plane, and a rectangular gap is etched thereon. A microstrip line orthogonal to the gap is etched on the other side of the dielectric substrate, so as to realize electromagnetic coupling excitation. In order to realize impedance matching and resonance state, a fan-shaped branch is used at the end of the feed microstrip line. The radius of the fan-shaped branch is adjusted to obtain the effect of impedance matching. Meanwhile, the characteristic impedance of the output microstrip line is 50 ohms. A gradual line impedance transformation section is introduced between the output microstrip line and the feed microstrip line to realize wideband impedance matching.

[0027] The present application proposes a printed vibrator antenna radiator, which is used as a polarization port 2 in Figure 3In the figure, 10 is a printed oscillator arm, 11 is a parallel double line transmission line, and 12 is a tapered line impedance transformation section. The vertical polarization port designed in the application is a balanced symmetrical oscillator antenna, which adopts a printed circuit structure, and the rectangular printed oscillators are respectively arranged on the upper and lower sides of the printed medium substrate. Since the microstrip line is a non-balanced structure, when feeding the balanced symmetrical printed oscillator, a Balun structure is introduced, and the application adopts a microstrip line tapered Balun. One end of the microstrip line printed Balun is a 50-ohm microstrip line, and the other end is a double-sided parallel double line, which is convenient for direct connection with the different surface printed symmetrical oscillator. In the feeding center of the radiator oscillator, a triangular transition structure is adopted, the oscillator center converges to the same position, and a different surface parallel double line is formed. In order to reduce the shielding effect of the two polarization ports, the different surface printed double line is bent, the bottom output of the printed symmetrical oscillator port is realized, and at the same time, the application adopts a reasonable different surface printed double line width, which ensures impedance matching, reduces the shielding and coupling influence of the printed symmetrical oscillator antenna on the magnetic electric dipole antenna, and ensures the electromagnetic isolation performance.

[0028] Embodiment:

[0029] The example proposes a kind of combination formula dual polarized antenna device based on magnetic electric dipole and printed symmetrical oscillator, and the performance simulation of the antenna is carried out using full-wave electromagnetic simulation software, and the simulation experimental result verifies the effectiveness of the combination formula dual polarized antenna device based on magnetic electric dipole and printed symmetrical oscillator proposed in the application.

[0030] The circuit characteristics of the combination formula dual polarized antenna based on magnetic electric dipole and printed symmetrical oscillator designed in the example are as shown in Figure 6 It can be seen from the figure that the VSWR of the two polarization ports of the antenna is less than 2 at the operating frequency point 2.5GHz, and the port isolation is about 23dB.

[0031] Figure 7 And Figure 8 The simulation results of the radiation direction patterns of the two polarization ports at the center frequency point are respectively given, and the three-dimensional gain direction pattern, the three-dimensional axial ratio direction pattern, the gain direction pattern in the xoz plane, the axial ratio direction pattern in the xoz plane, the gain direction pattern in the yoz plane and the axial ratio direction pattern in the yoz plane are respectively given. Figure 9 And Figure 10 The gain and axial ratio curves of the two polarization ports with frequency are respectively given. It can be seen that the gain of port 1 is higher than that of port 2, and the axial ratio is also higher than that of port 2.

Claims

1. A dual-polarized antenna device based on a hybrid structure of magnetoelectric dipoles and printed oscillators, characterized in that, It includes two polarization ports, one horizontal and one vertical, consisting of a magnetoelectric dipole antenna radiator and a printed dipole antenna radiator, respectively. The magnetoelectric dipole is excited by slot coupling. The metal ground plane is in the form of a printed circuit. Copper foil on one side of the dielectric substrate serves as the metal ground plane, on which a rectangular slot is etched. On the other side of the dielectric substrate, a microstrip line orthogonal to the ground plane is etched to form an electromagnetic coupling excitation effect. The printed circuit of the printed dipole antenna radiator is located in the slot of the magnetoelectric dipole antenna radiator. The field polarization direction of the printed dipole antenna radiator is orthogonal to the polarization direction of the magnetoelectric dipole, and the two work together. The magnetoelectric dipole antenna radiator is fed by a microstrip line side-feed method, and the output port is located at the bottom of the antenna; the printed dipole antenna radiator adopts a double-line bending method and is fed by a bottom-feed method, with the output port also located at the bottom of the antenna. The magnetoelectric dipole antenna radiator uses a Γ-shaped feed line to simultaneously excite the horizontal patch and the vertical short-circuited patch. The horizontal patch acts as a pair of electric dipoles, and the connected vertical short-circuited patch acts as a magnetic dipole and is simultaneously connected to the ground. The magnetoelectric dipole antenna radiator is excited by the Γ-shaped feed line located between the two vertical magnetic dipole patches. The Γ-shaped feed line is divided into three parts: the first part is a vertical section whose bottom end is connected to the coaxial inner core placed below the reflector. This vertical section, together with the adjacent vertical magnetic dipole patch, forms an air-medium structure. The microstrip transmission line, with a characteristic impedance of 50 ohms, transmits electrical signals to the second part of the Γ-type feed line. The second part is the horizontal section of the Γ-type feed line, which is at the same height as the horizontal electric dipole of the antenna radiator. Energy is transferred to the horizontal electric dipole and the vertical magnetic dipole through coupling. The horizontal section is inductive. The part close to another vertical patch is the third part of the Γ-type feed line. The third part and the vertical magnetic dipole form an open-circuit transmission line. The third part is capacitive. The capacitiveness of the third part cancels out the inductiveness of the second part to achieve good matching.

2. The dual-polarized antenna device based on a hybrid structure of magnetoelectric dipoles and printed oscillators according to claim 1, characterized in that, The electric dipole in the magnetoelectric dipole antenna radiator has an "8" shaped radiation pattern on its E-plane and an "O" shaped radiation pattern on its H-plane. The magnetic dipole is exactly the opposite of the electric dipole; its E-plane has an "O" shaped radiation pattern and its H-plane has an "8" shaped radiation pattern. When both the electric and magnetic dipoles are simultaneously excited by a signal, their forward radiation fields are superimposed in phase, while their backward radiation fields are canceled out of phase. The far-field radiation pattern formed by the superposition in the azimuth plane is heart-shaped. Therefore, the magnetoelectric dipole antenna can obtain a stable radiation pattern.

3. The dual-polarized antenna device based on a hybrid structure of magnetoelectric dipoles and printed oscillators according to claim 1, characterized in that, Aluminum plates are used as the processing material for the magnetic dipoles, which are simple to process due to their rectangular structure. The electric dipoles are implemented using a printed circuit structure, with the shape of the oscillator etched on a dielectric substrate. The dielectric substrate is placed above the magnetic dipoles, and the metal pattern of the electric dipoles and the metal arms of the magnetic dipoles are in direct contact. To achieve antenna impedance matching and resonance, a fan-shaped stub is used at the end of the feed microstrip line. The radius of the fan-shaped stub is adjusted to achieve impedance matching. At the other end of the microstrip line, the characteristic impedance of the output microstrip line is 50 ohms. A tapered impedance transformation section is introduced between the output microstrip line and the feed microstrip line to achieve broadband impedance matching.

4. The dual-polarized antenna device based on a hybrid structure of magnetoelectric dipoles and printed oscillators according to claim 1, characterized in that, In the printed dipole antenna radiator, rectangular printed dipoles are placed on the upper and lower sides of the printed dielectric substrate respectively; since the microstrip line is an unbalanced structure, a balun structure is introduced when feeding the balanced printed symmetrical dipoles, and a microstrip line graded balun is used. One end of the microstrip printed balun is a microstrip line with a characteristic impedance of 50 ohms, and the other end is a double-sided parallel double line. This facilitates direct connection with the non-circular printed symmetrical oscillator. At the feed center of the radiator oscillator, a triangular transition structure is adopted, and the centers of the oscillators converge to the same position to form a non-circular parallel double line. In order to reduce the blocking effect of the two polarization ports, the non-circular printed double line is bent to achieve bottom output of the printed symmetrical oscillator port.

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