Broadband end-fire millimeter wave complementary source circularly polarized antenna

Abstract

The invention relates to the technical field of wireless, and discloses a broadband end-fire millimeter wave complementary source circularly polarized antenna, which comprises a loop antenna, an electric dipole antenna and a reflecting surface structure, and is characterized in that the loop antenna is formed by a first group of micro-strips and metalized via holes which are arranged on an upper-layer PCB (Printed Circuit Board), a middle-layer PCB and a lower-layer PCB; the electric dipole antenna is formed by a second group of micro-strips and metalized via holes, the second group of micro-strips and the metalized via holes are arranged on the upper-layer PCB and the lower-layer PCB, a substrate integrated waveguide structure is arranged on the middle-layer PCB, a reflecting surface structure is formed on the upper-layer PCB and the lower-layer PCB, and the loop antenna and the electric dipole antenna are arranged on the same side of the reflecting surface structure. Two pairs of parallel complementary source antennas are formed, compared with a traditional complementary source structure, the adjustable branches are additionally arranged, more flexible impedance matching and axial ratio adjustment can be brought, the impedance and axial ratio bandwidth of the antenna can be further widened, the gain of the antenna can be enhanced through the additional arrangement of the antenna radiator, and the antenna structure is more compact. And the performance requirements of broadband and high gain are met.

Description

Technical Field

[0001] This invention relates to the field of wireless technology, and more specifically, to a broadband end-fire millimeter-wave complementary source circularly polarized antenna. Background Technology

[0002] Currently, millimeter-wave end-fire circularly polarized antennas have received widespread attention in fields such as 5G / 6G, satellite communication, radar, and imaging due to their unique advantages in end-fire directivity, anti-multipath interference, and high bandwidth of millimeter waves. However, most millimeter-wave broadband circularly polarized antennas are currently edge-fired, while end-fired millimeter-wave broadband circularly polarized antennas are relatively rare and suffer from problems such as narrow bandwidth and low gain.

[0003] In the prior art, a loop antenna is formed by using an S-shaped patch and a pair of obliquely placed metallized vias, and an electric dipole antenna is formed by a pair of obliquely placed metal patches and a pair of obliquely placed metallized vias. Since the magnetic dipoles and electric dipoles formed by the loop antenna are oblique, a pair of parallel magnetic dipoles and electric dipoles are formed, and the impedance and axial ratio coincidence bandwidth reaches 40%. However, this antenna is a side-emitting antenna.

[0004] Complementary source antennas are a type of broadband antenna structure widely used in broadband linear polarization and edge-fired circular polarization antenna designs. Therefore, this paper proposes a broadband end-fired millimeter-wave complementary source circular polarization antenna that simultaneously achieves the performance requirements of broadband and high gain. This antenna can be better applied in fields such as 5G / 6G communication, satellite internet ("StarNet Project"), intelligent connected vehicles (vehicle radar), drones and robots, to solve the problems existing in the current technology. Summary of the Invention

[0005] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. The summary section of this invention is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0006] To at least partially solve the above problems, the present invention provides a broadband end-fire millimeter-wave complementary source circularly polarized antenna, comprising: a loop antenna, an electric dipole antenna, and a reflector structure. The loop antenna is formed by a first set of microstrips and metallized vias arranged on an upper PCB board, a middle PCB board, and a lower PCB board. The electric dipole antenna is formed by a second set of microstrips and metallized vias arranged on the upper PCB board and the lower PCB board. A substrate integrated waveguide structure is provided on the middle PCB board. A reflector structure is formed on the upper PCB board and the lower PCB board. The loop antenna and the electric dipole antenna are disposed on the same side of the reflector structure.

[0007] Preferably, the first group of microstrips and metallized vias includes: a first microstrip and a second microstrip respectively disposed above and below the upper PCB board; a first connecting microstrip and a second connecting microstrip respectively disposed above and below the middle PCB board; a third microstrip and a fourth microstrip respectively disposed above and below the lower PCB board; a first metallized via and a second metallized via disposed on the upper PCB board; a third metallized via disposed on the middle PCB board; and a fourth metallized via and a fifth metallized via disposed on the lower PCB board. The second microstrip, the first metallized via, the first microstrip, the second metallized via, the first connecting microstrip, the third metallized via, the second connecting microstrip, the fourth metallized via, the fourth microstrip, the fifth metallized via, and the third microstrip are sequentially connected to form a loop antenna.

[0008] Preferably, the first microstrip and the second microstrip are arranged perpendicularly, the first microstrip and the fourth microstrip are arranged in parallel, and the second microstrip and the third microstrip are arranged in parallel.

[0009] Preferably, the second group of microstrips and metallized vias includes: a fifth microstrip and a sixth microstrip respectively disposed above and below the upper PCB board, a seventh microstrip and an eighth microstrip respectively disposed above and below the lower PCB board, a sixth metallized via disposed on the upper PCB board, and a seventh metallized via disposed on the lower PCB board. The fifth microstrip, the sixth metallized via, and the sixth microstrip are connected in sequence to form the first part of the electric dipole antenna. The seventh microstrip, the seventh metallized via, and the eighth microstrip are connected in sequence to form the second part of the electric dipole antenna. The first part and the second part are respectively disposed on both sides of the loop antenna to form the electric dipole antenna.

[0010] Preferably, the fifth and sixth microstrips are arranged vertically, the fifth and eighth microstrips are arranged in parallel, and the sixth and seventh microstrips are arranged in parallel.

[0011] Preferably, the substrate integrated waveguide structure includes: two adjacent rows of eighth metallized vias disposed on the middle layer PCB board, with copper plates disposed on the upper and lower sides of the two rows of eighth metallized vias, the side of the two rows of eighth metallized vias near the electric dipole antenna being its open end, and the other side being its feed port.

[0012] Preferably, the fifth microstrip and the eighth microstrip are respectively connected to the corresponding copper plate. In the horizontal direction, the fifth microstrip and the eighth microstrip are equivalent to a first electric dipole parallel to the opening end of the substrate integrated waveguide structure. The opening end of the substrate integrated waveguide structure is equivalent to a first magnetic dipole. The first electric dipole and the first magnetic dipole form a first pair of parallel complementary source antennas.

[0013] Preferably, in the vertical direction, the ring antenna is equivalent to a second magnetic dipole, and the sixth and seventh metallized vias located on both sides of the ring antenna are equivalent to second electric dipoles, with the second electric dipole and the second magnetic dipole forming a second pair of parallel complementary source antennas.

[0014] Preferably, the reflective surface structure includes: a row of ninth metallized vias disposed on the upper PCB board and a row of tenth metallized vias disposed on the lower PCB board.

[0015] Preferably, the end of the second microstrip away from the first metallized via extends toward one side of the substrate integrated waveguide structure, and the end of the third microstrip away from the fifth metallized via extends toward one side of the substrate integrated waveguide structure. The fifth microstrip extends away from the sixth metallized via at one end toward the side away from the loop antenna, the sixth microstrip extends away from the sixth metallized via at one end toward the side of the substrate integrated waveguide structure, the seventh microstrip extends away from the seventh metallized via at one end toward the side of the substrate integrated waveguide structure, and the eighth microstrip extends away from the seventh metallized via at one end toward the side away from the loop antenna.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects: The broadband end-fire millimeter-wave complementary source circularly polarized antenna of the present invention can form two pairs of parallel complementary source antennas through a loop antenna, an electric dipole antenna, and a substrate integrated waveguide structure. Compared with the traditional complementary source structure, this antenna structure adds adjustable stubs, thereby enabling more flexible impedance matching and axial ratio adjustment, further widening its impedance and axial ratio bandwidth. In addition, the increase of the antenna radiator can be used to enhance the antenna gain, achieving the performance requirements of broadband and high gain.

[0017] The broadband end-fire millimeter-wave complementary source circularly polarized antenna of the present invention, other advantages, objectives and features of the present invention will be apparent in part from the following description, and in part will be understood by those skilled in the art through study and practice of the invention. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the overall structure of the broadband end-fire millimeter-wave complementary source circularly polarized antenna described in this invention. Figure 2 This is an exploded structural diagram of the broadband end-fire millimeter-wave complementary source circularly polarized antenna described in this invention. Figure 3This is a schematic diagram of the loop antenna structure in the broadband end-fire millimeter-wave complementary source circularly polarized antenna described in this invention. Figure 4 This is a schematic diagram of the electric dipole antenna in the broadband end-fire millimeter-wave complementary source circularly polarized antenna described in this invention. Figure 5 This is a schematic diagram of the reflector structure in the broadband end-fire millimeter-wave complementary source circularly polarized antenna described in this invention. Figure 6 This is a schematic diagram of the structure of the first pair of parallel complementary source antennas in the broadband end-fire millimeter-wave complementary source circularly polarized antenna described in this invention. Figure 7 This is a schematic diagram of the structure of the second pair of complementary source antennas in the broadband end-fire millimeter-wave complementary source circularly polarized antenna described in this invention. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments, so that those skilled in the art can implement it based on the description.

[0020] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0021] like Figures 1-7 As shown, the present invention provides a broadband end-fire millimeter-wave complementary source circularly polarized antenna, comprising: a loop antenna 1, an electric dipole antenna 2, and a reflector structure 3. The loop antenna 1 is formed by a first set of microstrips and metallized vias arranged on an upper PCB board 5, a middle PCB board 6, and a lower PCB board 8. The electric dipole antenna 2 is formed by a second set of microstrips and metallized vias arranged on an upper PCB board 5 and a lower PCB board 8. A substrate integrated waveguide structure 4 is provided on the middle PCB board 6. The reflector structure 3 is formed on the upper PCB board 5 and the lower PCB board 8. The loop antenna 1 and the electric dipole antenna 2 are disposed on the same side of the reflector structure 3.

[0022] In the above scheme, the two microstrips of the electric dipole antenna 2 above the upper PCB board 5 and below the lower PCB board 8 are equivalent to a horizontal electric dipole parallel to the opening end of the substrate integrated waveguide structure 4, namely the first electric dipole 27. The opening end of the substrate integrated waveguide structure 4 is equivalent to a horizontal magnetic dipole, namely the first magnetic dipole 28, thus forming the first pair of parallel complementary source antennas. The loop antenna 1 is equivalent to a vertical magnetic dipole, i.e., the second magnetic dipole, and the two metallized vias of the electric dipole antenna 2 are equivalent to a vertical electric dipole, i.e., the second electric dipole 29, thus forming a second pair of parallel complementary source antennas.

[0023] Through the above structural design, the loop antenna 1, the electric dipole antenna 2, and the substrate integrated waveguide structure 4 can form two pairs of parallel complementary source antennas. Compared with the traditional complementary source structure, this antenna structure adds adjustable stubs, which can bring more flexible impedance matching and axial ratio adjustment, further widening its impedance and axial ratio bandwidth. In addition, the increase of the antenna radiator can be used to enhance the antenna gain, realizing the performance requirements of broadband and high gain.

[0024] like Figure 3 As shown, in one embodiment, the first group of microstrips and metallized vias includes: a first microstrip 9 and a second microstrip 10 respectively disposed above and below the upper PCB board 5; a first connecting microstrip 11 and a second connecting microstrip 12 respectively disposed above and below the middle PCB board 6; a third microstrip 13 and a fourth microstrip 14 respectively disposed above and below the lower PCB board 8; a first metallized via 19 and a second metallized via 20 disposed on the upper PCB board 5; a third metallized via 21 disposed on the middle PCB board 6; and a fourth metallized via 22 and a fifth metallized via 23 disposed on the lower PCB board 8. The second microstrip 10, the first metallized via 19, the first microstrip 9, the second metallized via 20, the first connecting microstrip 11, the third metallized via 21, the second connecting microstrip 12, the fourth metallized via 22, the fourth microstrip 14, the fifth metallized via 23 and the third microstrip 13 are connected in sequence to form a loop antenna 1.

[0025] Furthermore, the first microstrip 9 and the second microstrip 10 are arranged vertically, the first microstrip 9 and the fourth microstrip 14 are arranged in parallel, and the second microstrip 10 and the third microstrip 13 are arranged in parallel.

[0026] The aforementioned loop antenna 1 can be equivalent to a vertical magnetic dipole, which is a closed loop carrying current.

[0027] like Figure 4 As shown, in one embodiment, the second set of microstrips and metallized vias includes: a fifth microstrip 15 and a sixth microstrip 16 respectively disposed above and below the upper PCB board 5, a seventh microstrip 17 and an eighth microstrip 18 respectively disposed above and below the lower PCB board 8, a sixth metallized via 24 disposed on the upper PCB board 5, and a seventh metallized via 25 disposed on the lower PCB board 8. The fifth microstrip 15, the sixth metallized via 24, and the sixth microstrip 16 are sequentially connected to form the first part of the electric dipole antenna 2. The seventh microstrip 17, the seventh metallized via 25, and the eighth microstrip 18 are sequentially connected to form the second part of the electric dipole antenna 2. The first part and the second part are respectively disposed on both sides of the loop antenna 1 to form the electric dipole antenna 2.

[0028] Furthermore, the fifth microstrip 15 and the sixth microstrip 16 are arranged vertically, the fifth microstrip 15 and the eighth microstrip 18 are arranged in parallel, and the sixth microstrip 16 and the seventh microstrip 17 are arranged in parallel.

[0029] An electric dipole is composed of two point charges that are very close to each other, have equal charges but opposite signs. The first part and the second part of the electric dipole antenna 2 in the above scheme are equivalent to two point charges with equal charges but opposite signs. The two microstrips and two metallized vias in the first part and the second part of the electric dipole antenna 2 can be excited respectively, so as to be used as two electric dipoles.

[0030] like Figure 1 , Figure 2 and Figure 5 As shown, in one embodiment, the substrate integrated waveguide structure 4 includes: two adjacent rows of eighth metallized vias 41 disposed on the middle layer PCB board 6, copper plates 26 are respectively disposed on the upper and lower sides of the two rows of eighth metallized vias 41, the side of the two rows of eighth metallized vias 41 closest to the electric dipole antenna 2 is its open end, and the other side is its feed port.

[0031] The substrate integrated waveguide structure 4 is a microwave transmission line form achieved by constructing a periodic metallized via array on a low-loss dielectric substrate. It combines the low transmission loss and high Q value (quality factor) characteristics of traditional metal waveguides with the easy integration advantages of planar circuits. Its structure uses two rows of adjacent metallized vias to form an equivalent electric wall, which together with the copper cladding layers above and below to constrain the propagation of electromagnetic fields. In the above scheme, the upper and lower sides of the two adjacent eighth metallized vias 41 are covered by copper plates 26 to jointly constrain the propagation of electromagnetic fields. The upper copper plate 26 is set between the upper PCB board 5 and the middle PCB board 6, and the lower copper plate 26 is set between the middle PCB board 6 and the lower PCB board 8. The feed port of the substrate integrated waveguide structure 4 is used to connect to the feed power supply, and the other end is an open end used to form a pair of parallel complementary source antennas with the two microstrips of the electric dipole antenna 2.

[0032] like Figure 4 and Figure 6 As shown, in one embodiment, the fifth microstrip 15 and the eighth microstrip 18 are respectively connected to the corresponding copper plate 26. In the horizontal direction, the fifth microstrip 15 and the eighth microstrip 18 are equivalent to a first electric dipole 27 parallel to the opening end of the substrate integrated waveguide structure 4. The opening end of the substrate integrated waveguide structure 4 is equivalent to a first magnetic dipole 28. The first electric dipole 27 and the first magnetic dipole 28 form a first pair of parallel complementary source antennas.

[0033] When the fifth microstrip 15 is working normally, it needs to be connected to the sixth microstrip 16 and the sixth metallized via 24 to be excited. When the eighth microstrip 18 is working normally, it needs to be connected to the seventh microstrip 17 and the seventh metallized via 25 to be excited, so that the fifth microstrip 15 and the eighth microstrip 18 can form a horizontal electric dipole, namely the first electric dipole 27, thereby forming a pair of parallel complementary source antennas with the first magnetic dipole 28 equivalent to the opening end of the substrate integrated waveguide structure 4.

[0034] like Figure 7 As shown, in one embodiment, in the vertical direction, the loop antenna 1 is equivalent to a second magnetic dipole, and the sixth metallized via 24 and the seventh metallized via 25 located on both sides of the loop antenna 1 are equivalent to second electric dipoles 29. The second electric dipoles 29 and the second magnetic dipoles form a second pair of parallel complementary source antennas.

[0035] The sixth metallized via 24 and the seventh metallized via 25 of the electric dipole antenna 2 are arranged vertically. After being excited, they are equivalent to the second electric dipole 29, forming a second pair of parallel complementary source antennas with the loop antenna 1, which is equivalent to the second magnetic dipole.

[0036] The electric dipole antenna 2 of the present invention can be equivalent to a vertical electric dipole and a horizontal electric dipole, respectively. The opening ends of the loop antenna 1 and the substrate integrated waveguide structure 4 are equivalent to a vertical magnetic dipole and a horizontal magnetic dipole, respectively. Thus, the antenna of the present invention forms two pairs of parallel complementary source antennas and can realize end-fire radiation, while also achieving the performance requirements of broadband and high gain.

[0037] like Figure 1 and Figure 5 As shown, in one embodiment, the reflective surface structure 3 includes: a row of ninth metallized vias 31 disposed on the upper PCB board 5 and a row of tenth metallized vias 32 disposed on the lower PCB board 8.

[0038] The two rows of metallized vias on the upper PCB board 5 and the lower PCB board 8 form the antenna's reflective surface, enabling the antenna to have better directivity and gain.

[0039] In one embodiment, the end of the second microstrip 10 away from the first metallized via 19 extends toward one side of the substrate integrated waveguide structure 4, and the end of the third microstrip 13 away from the fifth metallized via 23 extends toward one side of the substrate integrated waveguide structure 4. The fifth microstrip 15 extends away from the sixth metallized via 24 at one end toward the side away from the ring antenna 1, the sixth microstrip 16 extends away from the sixth metallized via 24 at one end toward the side of the substrate integrated waveguide structure 4, the seventh microstrip 17 extends away from the seventh metallized via 25 at one end toward the side of the substrate integrated waveguide structure 4, and the eighth microstrip 18 extends away from the seventh metallized via 25 at one end toward the side away from the ring antenna 1.

[0040] The second microstrip 10, the third microstrip 13, the fifth microstrip 15, the sixth microstrip 16, the seventh microstrip 17, and the eighth microstrip 18 serve as stubs of the antenna and can be adjusted as needed, thereby providing more flexible impedance matching and axial ratio adjustment, and further widening its impedance and axial ratio bandwidth.

[0041] In one embodiment, a broadband end-fire millimeter-wave complementary source circularly polarized antenna includes: The antenna was placed in a standard microwave anechoic chamber test environment, and the operating frequency band of the antenna was configured in the standard microwave anechoic chamber test environment. At the same time, a discretized frequency scanning sequence was determined based on the configuration results, and the two-dimensional parameter traversal space was performed for each frequency point in the frequency scanning sequence. Based on the two-dimensional parameter traversal space, signal control parameters for each phase difference and different amplitude ratios are generated respectively. Based on the signal control parameters, excitation signals at each frequency point are sequentially transmitted to the antenna in a standard microwave anechoic chamber test environment. The measurement device based on the transmission result control standard microwave anechoic chamber test environment measures the key performance parameters of the antenna in the end-fire direction. The key performance parameters include the measured axial ratio and measured gain value at each frequency point and under each signal control parameter. The measured axial ratio and measured gain values ​​under different signal control parameters at each frequency point are summarized to generate two-dimensional plane data, and preset performance constraints are obtained based on the management terminal. Based on preset performance constraints, the two-dimensional plane data is filtered, and the optimal control parameter pair for the signal at each frequency point is obtained based on the filtering results. A calibration data mapping table is generated based on the optimal control parameters of the signal, and the calibration data mapping table is stored in the built-in storage unit. The target operating frequency corresponding to the current antenna is detected, and the calibration data mapping table is accessed based on the target operating frequency to extract the optimal phase control quantity and the optimal amplitude ratio control parameter corresponding to the target operating frequency parameter. Based on the optimal phase control quantity and the optimal amplitude ratio control parameter, the phase and amplitude ratio of one of the two signals in the current antenna are adjusted, and the adjusted two signals are returned to the electric dipole and magnetic dipole in the antenna respectively; Spatial calibration of electromagnetic waves using electric and magnetic dipoles yields circularly polarized electromagnetic waves in the terminal direction.

[0042] In this embodiment, the broadband end-fire millimeter-wave complementary source circularly polarized antenna refers to an antenna device that operates in the millimeter-wave band, employs a complementary source structure (including electric dipoles and magnetic dipoles), and is capable of generating circularly polarized electromagnetic waves in the end-fire direction.

[0043] In this embodiment, the discretized frequency scan sequence refers to a frequency sequence composed of discrete points within the antenna's operating frequency band, used for systematic testing and calibration.

[0044] In this embodiment, the two-dimensional parameter traversal space refers to a two-dimensional space composed of two parameters: phase difference and amplitude ratio. All possible combinations are traversed within this space to test antenna performance.

[0045] In this embodiment, the signal control parameters refer to the parameters that control the input signal to the antenna, including the phase difference and amplitude ratio.

[0046] In this embodiment, key performance parameters refer to key indicators for evaluating antenna performance, including measured axial ratio and measured gain.

[0047] In this embodiment, two-dimensional planar data refers to a two-dimensional data set formed by using phase difference and amplitude ratio as coordinate axes, and corresponding to the measured axis ratio and measured gain value of each point.

[0048] In this embodiment, the preset performance constraints refer to pre-set performance requirements, such as the axis ratio threshold or the minimum gain, which are used to screen for the optimal parameters.

[0049] In this embodiment, the optimal signal control parameter pair refers to the optimal combination of phase difference and amplitude ratio that enables the antenna performance to meet preset conditions at a specific frequency.

[0050] In this embodiment, the calibration data mapping table refers to a data table that stores the mapping relationship between frequency points and corresponding optimal control parameter pairs of signals, and is used for real-time calibration.

[0051] In this embodiment, the optimal phase control value refers to the phase adjustment value required to optimize antenna performance at a specific frequency.

[0052] In this embodiment, the optimal amplitude ratio control parameter refers to the amplitude ratio adjustment value required to optimize antenna performance at a specific frequency.

[0053] The beneficial effects of the above technical solution are as follows: Through a systematic testing and calibration process, high-performance circular polarization characteristics of the antenna in the millimeter-wave band are achieved. First, in a standard microwave anechoic chamber testing environment, the impact of different phase differences and amplitude ratios on key antenna performance parameters (such as axial ratio and gain) is comprehensively evaluated based on a discrete frequency scanning sequence and two-dimensional parameter traversal space, thereby generating optimized signal control parameters. Second, the optimal signal control parameter pairs at each frequency point are selected through preset performance constraints, and a calibration data mapping table is constructed and stored in the built-in storage unit. In practical applications, the optimal phase control quantity and optimal amplitude ratio control parameter can be quickly retrieved according to the target operating frequency, and the phase and amplitude ratio of the two signals can be dynamically adjusted to drive the electric dipole and magnetic dipole to work together, realizing the spatial synthesis of electromagnetic waves. This ensures that the antenna always generates low axial ratio and high gain circularly polarized electromagnetic waves in the end-fire direction, improving the stability and efficiency of broadband operation and enhancing the adaptability and reliability of the antenna.

[0054] In one embodiment, a broadband end-fire millimeter-wave complementary source circularly polarized antenna includes: Obtain the substrate integrated waveguide feed network corresponding to the substrate integrated waveguide structure, and apply a sweep frequency signal to the input end of the substrate integrated waveguide feed network based on the control terminal, while simultaneously measuring the reflection coefficient and axial ratio frequency response of the antenna input port; The obtained reflection coefficient is compared with a preset threshold, and the impedance matching adjustment mechanism is activated when the reflection coefficient does not meet the preset threshold requirement. The control circuit adjusts the equivalent electrical parameters of the loop antenna based on the impedance matching adjustment mechanism, and simultaneously measures the changing trend of the reflection coefficient. When the trend of change becomes flat, the intermediate optimized state of the reflection coefficient is obtained, and the control circuit adjusts the equivalent electrical parameters of the electric dipole antenna. Based on the adjustment results, the target state of the reflection coefficient is monitored in real time until the preset threshold is met in the entire frequency band. When the reflection coefficient meets the preset threshold across the entire frequency band, the impedance matching adjustment is determined to be complete, and the obtained axial ratio frequency response is compared with the preset standard. When the shaft ratio frequency response does not meet the preset standard, the shaft ratio optimization mechanism is activated; Based on the startup results, the values ​​of the axial ratio frequency response at different frequency points within the frequency band are determined, and the axial ratio frequency curve is generated based on the values ​​of the axial ratio frequency response at different frequency points within the frequency band. The key frequency points and performance offsets are determined based on the axial ratio frequency curve, and the effective amplitude ratio and effective phase difference of the loop antenna and the electric dipole antenna are determined based on the key frequency points and performance offsets. Based on the tuning characteristics of the loop antenna and the electric dipole antenna, the effective amplitude ratio and effective phase difference are analyzed to generate a composite control command that simultaneously controls the loop antenna and the electric dipole antenna circuit. The circuit is controlled collaboratively based on composite control commands, and the reflection coefficient and axial ratio frequency response of the antenna input port are remeasured. When the reflection coefficient and axial ratio frequency response of the antenna input port still do not meet the corresponding preset threshold and preset standard, the composite control command is iteratively updated until the corresponding preset threshold and preset standard are met, and the antenna verification configuration is completed.

[0055] In this embodiment, the substrate integrated waveguide feed network refers to a planar waveguide structure fabricated on a dielectric substrate with sidewalls formed by an array of metallized vias, used for feeding the antenna and distributing signals.

[0056] In this embodiment, the impedance matching adjustment mechanism refers to a control process that automatically adjusts the antenna's equivalent electrical parameters to reduce the reflection coefficient at the antenna input port to meet preset requirements.

[0057] In this embodiment, the axial ratio optimization mechanism refers to an automatic control process specifically designed to improve the circular polarization performance of the antenna and achieve the required axial ratio frequency response by adjusting the amplitude and phase.

[0058] In this embodiment, the axial ratio frequency curve refers to the characteristic curve plotted as the axial ratio value of the antenna changes with frequency.

[0059] In this embodiment, the key frequency point and performance offset refer to the specific frequency point selected on the shaft ratio frequency curve where the performance (such as shaft ratio) is not up to standard or needs to be optimized (e.g., the frequency point with the worst shaft ratio), and the difference between the performance index and the target value at that point.

[0060] In this embodiment, the effective amplitude ratio and effective phase difference refer to the optimal signal amplitude ratio and phase difference values ​​that need to be set between the loop antenna and the electric dipole antenna in order to achieve optimal circular polarization radiation.

[0061] In this embodiment, the composite control command refers to a set of control signals that can simultaneously coordinate the circuitry (such as tuning elements) of the loop antenna and the electric dipole antenna.

[0062] The beneficial effects of the above technical solution are as follows: By introducing an automated impedance matching adjustment mechanism and axial ratio optimization mechanism, efficient and accurate calibration of antenna performance is achieved. First, the reflection coefficient is detected by a frequency sweep signal, and impedance matching adjustment is initiated. By adjusting the equivalent electrical parameters of the loop antenna and the electric dipole antenna in steps, the reflection coefficient quickly reaches the preset threshold across the entire frequency band. Subsequently, the axial ratio optimization is automatically initiated. Based on the generated axial ratio frequency curve, key frequency points are analyzed to calculate the optimal effective amplitude ratio and effective phase difference. Composite control commands are generated to perform coordinated tuning of the two antenna elements, and iterative updates are performed until all indicators meet the standards simultaneously. This significantly reduces the complexity and time cost of traditional manual debugging, ensuring that the antenna has stable and good impedance matching and circular polarization performance in the broadband millimeter wave range, and improving the antenna's production efficiency and reliability.

[0063] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0064] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0065] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the present invention, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A broadband end-fire millimeter-wave complementary source circularly polarized antenna, characterized in that, include: The ring antenna (1), the electric dipole antenna (2), and the reflector structure (3) are provided. The ring antenna (1) is formed by a first set of microstrip and metallized vias arranged on the upper PCB board (5), the middle PCB board (6), and the lower PCB board (8). The electric dipole antenna (2) is formed by a second set of microstrip and metallized vias arranged on the upper PCB board (5) and the lower PCB board (8). The middle PCB board (6) is provided with a substrate integrated waveguide structure (4). The upper PCB board (5) and the lower PCB board (8) form the reflector structure (3). The ring antenna (1) and the electric dipole antenna (2) are located on the same side of the reflector structure (3).

2. The broadband end-fire millimeter-wave complementary source circularly polarized antenna according to claim 1, characterized in that, The first group of microstrips and metallized vias includes: a first microstrip (9) and a second microstrip (10) respectively disposed above and below the upper PCB board (5); a first connecting microstrip (11) and a second connecting microstrip (12) respectively disposed above and below the middle PCB board (6); a third microstrip (13) and a fourth microstrip (14) respectively disposed above and below the lower PCB board (8); a first metallized via (19) and a second metallized via (20) disposed on the upper PCB board (5); a third metallized via (21) disposed on the middle PCB board (6); and a fourth metallized via (22) and a fifth metallized via (23) disposed on the lower PCB board (8). The second microstrip (10), the first metallized via (19), the first microstrip (9), the second metallized via (20), the first connecting microstrip (11), the third metallized via (21), the second connecting microstrip (12), the fourth metallized via (22), the fourth microstrip (14), the fifth metallized via (23), and the third microstrip (13) are connected in sequence to form a loop antenna (1).

3. The broadband end-fire millimeter-wave complementary source circularly polarized antenna according to claim 2, characterized in that, The first microstrip (9) and the second microstrip (10) are arranged vertically, the first microstrip (9) and the fourth microstrip (14) are arranged in parallel, and the second microstrip (10) and the third microstrip (13) are arranged in parallel.

4. The broadband end-fire millimeter-wave complementary source circularly polarized antenna according to claim 2, characterized in that, The second group of microstrips and metallized vias includes: a fifth microstrip (15) and a sixth microstrip (16) respectively disposed above and below the upper PCB board (5), a seventh microstrip (17) and an eighth microstrip (18) respectively disposed above and below the lower PCB board (8), a sixth metallized via (24) disposed on the upper PCB board (5), and a seventh metallized via (25) disposed on the lower PCB board (8); The fifth microstrip (15), the sixth metallized via (24) and the sixth microstrip (16) are connected in sequence to form the first part of the electric dipole antenna (2), and the seventh microstrip (17), the seventh metallized via (25) and the eighth microstrip (18) are connected in sequence to form the second part of the electric dipole antenna (2). The first part and the second part are respectively disposed on both sides of the loop antenna (1) to form the electric dipole antenna (2).

5. The broadband end-fire millimeter-wave complementary source circularly polarized antenna according to claim 4, characterized in that, The fifth microstrip (15) and the sixth microstrip (16) are arranged vertically, the fifth microstrip (15) and the eighth microstrip (18) are arranged in parallel, and the sixth microstrip (16) and the seventh microstrip (17) are arranged in parallel.

6. The broadband end-fire millimeter-wave complementary source circularly polarized antenna according to claim 4, characterized in that, The substrate integrated waveguide structure (4) includes: two adjacent rows of eighth metallized vias (41) on the middle layer PCB board (6), copper plates (26) are respectively provided on the upper and lower sides of the two rows of eighth metallized vias (41), and the side of the two rows of eighth metallized vias (41) closest to the electric dipole antenna (2) is its opening end, and the other side is its feed port.

7. The broadband end-fire millimeter-wave complementary source circularly polarized antenna according to claim 6, characterized in that, The fifth microstrip (15) and the eighth microstrip (18) are respectively connected to the corresponding copper plate (26). In the horizontal direction, the fifth microstrip (15) and the eighth microstrip (18) are equivalent to a first electric dipole (27) parallel to the opening end of the substrate integrated waveguide structure (4). The opening end of the substrate integrated waveguide structure (4) is equivalent to a first magnetic dipole (28). The first electric dipole (27) and the first magnetic dipole (28) form a first pair of parallel complementary source antennas.

8. The broadband end-fire millimeter-wave complementary source circularly polarized antenna according to claim 4, characterized in that, In the vertical direction, the ring antenna (1) is equivalent to a second magnetic dipole, and the sixth metallized via (24) and the seventh metallized via (25) located on both sides of the ring antenna (1) are equivalent to a second electric dipole (29). The second electric dipole (29) and the second magnetic dipole form a second pair of parallel complementary source antennas.

9. The broadband end-fire millimeter-wave complementary source circularly polarized antenna according to claim 1, characterized in that, The reflective surface structure (3) includes: a row of ninth metallized vias (31) disposed on the upper PCB board (5) and a row of tenth metallized vias (32) disposed on the lower PCB board (8).

10. The broadband end-fire millimeter-wave complementary source circularly polarized antenna according to claim 4, characterized in that, The second microstrip (10) extends away from the first metallized via (19) towards one side of the substrate integrated waveguide structure (4), and the third microstrip (13) extends away from the fifth metallized via (23) towards one side of the substrate integrated waveguide structure (4). The fifth microstrip (15) extends away from the sixth metallized via (24) towards the side away from the ring antenna (1), the sixth microstrip (16) extends away from the sixth metallized via (24) towards the side of the substrate integrated waveguide structure (4), the seventh microstrip (17) extends away from the seventh metallized via (25) towards the side of the substrate integrated waveguide structure (4), and the eighth microstrip (18) extends away from the seventh metallized via (25) towards the side away from the ring antenna (1).

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