Miniaturized broadband polarized antenna based on single ridge horn and log-periodic antenna

Abstract

The application relates to the technical field of microwave antennas, in particular to a small-sized wideband polarization antenna based on a single-ridge horn and a log-periodic antenna, which is convenient to process, stable and reliable, small in size, and characterized in that the small-sized wideband polarization antenna comprises a dual-polarization diversity mode of vertical polarization and horizontal polarization, electromagnetic fields of two polarization ports are orthogonal in a far radiation zone, polarization port one adopts a small-sized printed log-periodic antenna with a locally buried dielectric, and polarization port two adopts a single-ridge ultra-wideband horn antenna; compared with the prior art, the scheme is simple in design, convenient in processing and assembly, low in cost, beneficial to engineering application, suitable for application in a dual-polarization radar system, an electronic countermeasure system and a wireless communication system, and has relatively important application value.

Description

TECHNICAL FIELD

[0001] The present application relates to the microwave antenna technical field, specifically speaking, it is a kind of small-sized wideband polarized antenna based on single-ridge horn and log-periodic antenna, which is convenient to process, stable and reliable and small in size. BACKGROUND

[0002] With the rapid development of new system radar, electronic countermeasure and telemetry technologies, more and more antenna forms are installed on aircraft carriers, and the system has higher and higher requirements for the indicators of aircraft antennas. In order to more comprehensively utilize the information resources of electromagnetic waves, the current full-polarized electronic information system has been widely concerned and applied. Therefore, polarization diversity antennas have also been extensively researched and applied, and various types of dual-polarized antenna forms have appeared. Dual-polarized antenna is a commonly used polarization-sensitive antenna form, which usually contains two polarization ports, and the two polarization ports radiate and receive polarization-orthogonal electromagnetic component signals, so as to realize the function of polarization diversity. There are many implementation schemes of dual-polarized antenna, and according to specific application occasions, corresponding antenna types can be selected, such as dual-polarized microstrip patch antenna, dual-polarized dipole antenna, dual-polarized slot antenna, dual-polarized reflector antenna, dual-polarized dielectric resonator antenna and dual-polarized horn antenna. The dual-polarized microstrip patch antenna is simple in design, low in cost and suitable for array application. The dual-polarized slot antenna is a kind of antenna that relies on the electromagnetic energy excited by a slot to radiate to free space, and it is focused on because it is easy to realize wideband characteristics, and it needs to load a metal reflection floor to obtain a unidirectional radiation pattern. The dual-polarized dipole antenna is simple in structure, flexible in design, low in cost, easy to expand impedance bandwidth and stable in direction pattern, and is suitable for base station communication system application. The dual-polarized horn antenna is simple in structure, convenient to process, stable and reliable, and is suitable for application in various occasions.

[0003] In actual engineering application, the miniaturization of dual-polarized antenna is an important task. Compared with the traditional single-polarized antenna, the size of dual-polarized antenna is generally larger, so it is of great significance to compress the size of dual-polarized antenna. The methods of antenna miniaturization include improving the dielectric parameters and magnetic permeability of the medium space, using fractal structure and loading technology, etc. SUMMARY

[0004] The present application is proposed to solve the problems and deficiencies in the prior art, and provides a small-sized wideband polarized antenna based on single-ridge horn and log-periodic antenna suitable for aircraft carrier platform.

[0005] The present application achieves the following effects by the following measures:

[0006] The application discloses a miniaturized broadband polarized antenna based on a single-ridge horn and a log-periodic antenna, which is characterized by a dual-polarization diversity mode of vertical polarization and horizontal polarization, and two polarization ports are orthogonal in electromagnetic fields in a far radiation zone, wherein a polarization port one adopts a miniaturized printed log-periodic antenna with a dielectric local embedding, and a polarization port two adopts a single-ridge ultra-wideband horn antenna; printed dipoles in the printed log-periodic antenna are printed on a microwave dielectric substrate in a periodic manner, the longest dipole corresponding to a low frequency is set as a first printed dipole, the length of the first printed dipole is 2L1, the width of the first printed dipole is W1, the spacing between the first printed dipole and a second printed dipole is d1, and the structure of the printed log-periodic antenna satisfies the following formulae according to the periodic manner:

[0007] L n+1 / L n =τ1(1), W n+1 / W n =τ2(2), d n+1 / d n =τ2(3), wherein τ1, τ1 and τ1 are periodic laws, the three parameters are adjusted respectively, and the electrical performance of the printed log-periodic antenna is optimized jointly; at the low frequency, in order to reduce electromagnetic wave reflection and improve impedance matching performance, a wave absorbing resistor is loaded at the end of a collection line of antenna feeding, so that the voltage standing wave ratio of the printed log-periodic antenna is reduced effectively; in order to improve the radiation efficiency and impedance matching performance of the antenna, high dielectric constant dielectric substrates are loaded at positions corresponding to low frequency dipoles on both sides of the dielectric substrate of the printed log-periodic antenna, and the situation at high frequency positions remains unchanged, so that the radiation performance of the printed log-periodic antenna is adjusted, the concept of equivalent dielectric constant ε e is introduced according to the influence of the dielectric, and is determined by the following formula: ε e =1+q(ε r -1)(4), wherein q is a filling factor, q=1 when the antenna is filled in the dielectric completely, q=0 when the antenna is filled in air completely, 0 r is the relative dielectric constant of the dielectric plate, for the antenna embedded in the dielectric completely, q=1, so that the equivalent dielectric constant is approximately equal to the relative dielectric constant, and the wavelength λ g of the electromagnetic wave in the dielectric embedded antenna is calculated by the following formula: wherein c is the speed of light in vacuum, and f0 is the center frequency of the antenna.

[0008] The polarization port two adopts a single-ridge ultra-wideband horn antenna, which is provided with a single-ridge ultra-wideband open horn antenna radiator, and includes an exponential curve-shaped metal ridge, a metal reflecting floor serving as a mirror, a metal resonant cavity for feeding, a coaxial line port for feeding and a probe, and the ridge curve adopts an exponential curve form in the ridge horn section, as shown in the following formula:

[0009] Where: 0 < z < h_horn, h_horn is the height of the micro-horn, and z is the coordinate of the horn central axis.

[0010] For the antenna of polarization port 1 of the present invention, a non-conductive via array is etched on the loaded dielectric substrate, which plays a role in adjusting the impedance and radiation characteristics. Through local dielectric burial and lumped line resistance loading, the printed log-periodic antenna designed by the present invention can achieve the compression of the horizontal size of the antenna.

[0011] For the horn antenna of polarization port 2 of the present invention, the width of the feeding resonant cavity is a, and the length is h_cavity. In order to improve the impedance matching effect of the horn antenna and reduce the standing wave, the resonant cavity of the antenna adopts a tapered cavity.

[0012] In summary, the present invention proposes a design scheme and antenna structure device of a miniaturized polarization diversity antenna based on a single-ridge horn and a log-periodic antenna. The antenna device adopts a combined miniaturized broadband antenna structure to achieve horizontal and vertical polarization diversity working modes. The two polarization ports of the antenna are respectively a single-ridge horn open-ended horn antenna radiator and a partially buried printed log-periodic antenna radiator. By reasonably configuring the positions between the single-ridge horn open-ended horn antenna radiator and the partially buried printed log-periodic antenna radiator, good polarization isolation and cross-polarization performance can be achieved. Based on the mirror principle of electromagnetic fields, a single-ridge horn antenna is used to compress the antenna size; by optimizing the design of the reflector floor structure and shape of the single-ridge horn antenna, the impedance and radiation pattern performance of the single-ridge horn antenna are adjusted. The polarization diversity antenna scheme designed in the present invention has a simple design, is convenient for processing and assembly, has a low cost, and is beneficial to engineering applications. The miniaturized polarization diversity antenna device designed in the present invention is suitable for application in dual-polarization radar systems, electronic countermeasure systems, and wireless communication systems, and has relatively important application value. Description of the Drawings:

[0013] Figure 1 is the structural schematic diagram of the present invention, Figure 1 (a) is a perspective view, Figure 1 (b) is a front view, Figure 1 [[ID=2I]](c) is a rear view, Figure 1 (d) is a left view, Figure 1 (e) is a right view, Figure 1 (f) is a top view, Figure 1 (g) is a bottom view.

[0014] Figure 2 is the structural diagram of the single-ridge horn antenna radiator (polarization port 2) of the present invention, where Figure 2 (a) is a perspective view, Figure 2 (b) is a front view, Figure 2(c) is the rear view. Figure 2 (d) is the left view. Figure 2 (e) is the right view. Figure 2 (f) is the top view. Figure 2 (g) is the bottom view.

[0015] Figure 3 This is a structural diagram of the embedded printed log-periodic antenna radiator (polarization port 1) in this invention, wherein... Figure 3 (a) is a 3D diagram. Figure 3 (b) is the front view. Figure 3 (c) is the rear view. Figure 3 (d) is the left view. Figure 3 (e) is the right view. Figure 3 (f) is the top view. Figure 3 (g) is the bottom view.

[0016] Figure 4 This is a schematic diagram of the structure of the printed log-periodic antenna radiator in this invention, wherein... Figure 4 (a) is a 3D diagram. Figure 4 (b) is the front view. Figure 4 (c) is the rear view. Figure 4 (d) is the left view. Figure 4 (e) is the right view. Figure 4 (f) is the top view. Figure 4 (g) is the bottom view.

[0017] Figure 5 The following are simulation results of the circuit characteristics of the antenna port of the present invention, wherein... Figure 5 (a) is the VSWR of port 1. Figure 5 (b) is the VSWR of port 2. Figure 5 (c) Isolation between ports.

[0018] Figure 6 The above are simulation results of the radiation characteristics of port 1 at a frequency of 1.7 GHz in the embodiment. Figure 6 (a) is the three-dimensional gain pattern. Figure 6 (b) is a three-dimensional axis ratio pattern. Figure 6 (c) shows the gain pattern in the xoz plane. Figure 6 (d) shows the gain pattern in the yoz plane.

[0019] Figure 7 These are simulation results of the radiation characteristics of port 2 at a frequency of 1.7 GHz in this embodiment of the invention. Figure 7 (a) is the three-dimensional gain pattern. Figure 7 (b) is the three-dimensional axis ratio pattern. Figure 7 (c) is the gain pattern on the xoz plane. Figure 7(d) is the gain pattern on the yoz plane.

[0020] Figure 8 These are simulation results of the radiation characteristics of port 1 at a frequency of 2.3 GHz in this embodiment of the invention. Figure 8 (a) is the three-dimensional gain pattern. Figure 8 (b) is the three-dimensional axis ratio pattern. Figure 8 (c) is the gain pattern on the xoz plane. Figure 8 (d) is the gain pattern on the yoz plane.

[0021] Figure 9 These are simulation results of the radiation characteristics of port 2 at a frequency of 2.3 GHz in this embodiment of the invention. Figure 9 (a) is the three-dimensional gain pattern. Figure 9 (b) is the three-dimensional axis ratio pattern. Figure 9 (c) is the gain pattern on the xoz plane. Figure 9 (d) is the gain pattern on the yoz plane.

[0022] Figure 10 These are simulation results of the radiation characteristics of port 1 at a frequency of 3GHz in this embodiment of the invention. Figure 10 (a) is the three-dimensional gain pattern. Figure 10 (b) is the three-dimensional axis ratio pattern. Figure 10 (c) is the gain pattern on the xoz plane. Figure 10 (d) is the gain pattern on the yoz plane.

[0023] Figure 11 These are simulation results of the radiation characteristics of port 2 at a frequency of 3GHz in this embodiment of the invention. Figure 11 (a) Three-dimensional gain pattern Figure 11 (b) is the three-dimensional axis ratio pattern. Figure 11 (c) is the gain pattern on the xoz plane. Figure 11 (d) is the gain pattern on the yoz plane.

[0024] Figure 12 Simulation results of the radiation characteristics of port 1 at a frequency of 4 GHz, where Figure 12 (a) is the three-dimensional gain pattern. Figure 12 (b) is the three-dimensional axis ratio pattern. Figure 12 (c) is the gain pattern on the xoz plane. Figure 12 (d) Gain pattern in the yoz plane.

[0025] Figure 13 These are simulation results of the radiation characteristics of port 2 at a frequency of 4 GHz in this embodiment of the invention. Figure 13 (a) is the three-dimensional gain pattern.Figure 13 (b) is the three-dimensional axis ratio pattern. Figure 13 (c) is the gain pattern on the xoz plane. Figure 13 (d) is the gain pattern on the yoz plane.

[0026] Figure 14 These are simulation results of the radiation characteristics of port 1 at a frequency of 5 GHz in this embodiment of the invention. Figure 14 (a) is the three-dimensional gain pattern. Figure 14 (b) is the three-dimensional axis ratio pattern. Figure 14 (c) is the gain pattern on the xoz plane. Figure 14 (d) is the gain pattern on the yoz plane.

[0027] Figure 15 These are simulation results of the radiation characteristics of port 2 at a frequency of 5 GHz in this embodiment of the invention. Figure 15 (a) Three-dimensional gain pattern Figure 15 (b) is the three-dimensional axis ratio pattern. Figure 15 (c) is the gain pattern on the xoz plane. Figure 15 (d) is the gain pattern on the yoz plane.

[0028] Reference numerals in the figures: 1 is the single-ridge horn feed cavity, 2 is the printed log-periodic antenna radiator, 3 is the ground plane of the single-ridge horn antenna radiator, 4 is the buried dielectric substrate of the printed log-periodic antenna radiator, 5 is the ridge of the single-ridge horn antenna radiator, 6 is the coaxial feed port of the single-ridge horn antenna radiator, 7 is the non-conductive via on the buried dielectric substrate of the printed log-periodic antenna radiator, 8 is the printed vibrator of the printed log-periodic antenna radiator, and 9 is the dielectric substrate of the printed log-periodic antenna radiator. Detailed implementation method:

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0030] This invention, based on an aircraft carrier platform, proposes a design scheme and device for a miniaturized polarization diversity antenna based on a single-ridge horn and a log-periodic antenna. It employs a dual-polarization diversity approach with vertical and horizontal polarization, ensuring that the electromagnetic fields of the two polarization ports are approximately orthogonal in the far-field radiation region, radiating and sensing the orthogonal polarization components of the electromagnetic waves. Considering the limited antenna installation space on actual aircraft carrier platforms, antenna miniaturization has become a crucial technical requirement. In the proposed polarization diversity antenna design, the dual-polarization antenna uses a combined miniaturized orthogonal polarization antenna diversity method. One polarization port uses a miniaturized printed log-periodic antenna with localized dielectric embedding, defined as polarization port 1; the other polarization port uses a single-ridge ultra-wideband horn antenna, defined as polarization port 2. Based on the mirror principle, miniaturization of the ultra-wideband horn antenna is achieved. The antenna radiators of the two polarization ports are tightly assembled together, and through a reasonable spatial arrangement of the antennas, the approximately orthogonal relationship of the radiation fields of the two polarization radiators is achieved.

[0031] The two polarization radiation ports of this invention employ different types and structures, allowing for relatively independent design and reducing design complexity. The overall polarization diversity antenna structure is simple, easy to fabricate and assemble, and suitable for practical engineering applications. The miniaturized polarization diversity antenna structure model based on a single-ridge horn and a log-periodic antenna designed in this invention is shown below. Figure 1 As shown. In Figure 1 In the diagram, 1 is the single-ridge horn feed cavity, 2 is the printed log-periodic antenna radiator, 3 is the ground plane of the single-ridge horn antenna radiator, 4 is the buried dielectric substrate of the printed log-periodic antenna radiator, 5 is the ridge of the single-ridge horn antenna radiator, and 6 is the coaxial feed port of the single-ridge horn antenna radiator. Figure 2 This is a structural diagram of a single-ridged horn antenna radiator (polarization port 2). Figure 3 This is a structural diagram of a printed dipole antenna radiator (polarization port 1). Figure 2 In the diagram, 7 represents a non-conductive via on the buried dielectric substrate of the printed log-periodic antenna radiator, 8 represents a printed vibrator of the printed log-periodic antenna radiator, and 9 represents the dielectric substrate of the printed log-periodic antenna radiator. Figure 3 Schematic diagram of a buried printed log-periodic antenna radiator (polarization port 1).

[0032] This invention designs a miniaturized printed log-periodic antenna with compressed lateral dimensions, the structure of which is as follows: Figure 3 As shown, the printed oscillator is printed on a microwave dielectric substrate according to a periodic pattern, and its structure is as follows. Figure 4 As shown. Assuming the longest element at low frequencies, i.e., the first printed element, has a length of 2L1 and a width of W1, and the distance between the first and second elements is d1, the structure of the designed printed log-periodic antenna satisfies the following formula according to the periodicity:

[0033] L n+1 / L n =τ1(1), W n+1 / W n =τ2(2),d n+1 / d n =τ2(3)

[0034] In the formula, τ1, τ1, and τ1 represent periodic laws. These three parameters are adjusted separately to jointly optimize the electrical performance of the printed log-periodic antenna.

[0035] In the miniaturization design of printed log-periodic antennas, on the one hand, to reduce electromagnetic wave reflection and improve impedance matching performance at low frequencies, wave-absorbing resistors are loaded at the ends of the antenna feed lines, effectively reducing the voltage standing wave ratio (VSWR) of the printed log-periodic antenna. On the other hand, to improve the antenna's radiation efficiency and impedance matching performance, this invention proposes a partial dielectric burial antenna miniaturization scheme. Specifically, a dielectric substrate with a higher dielectric constant is loaded on both sides of the dielectric substrate of the printed log-periodic antenna, corresponding to the positions of several low-frequency elements, while the situation at high-frequency positions remains unchanged, achieving the goal of adjusting the radiation performance of the printed log-periodic antenna. Dielectric burial technology is an effective antenna miniaturization technique. By burying the antenna in an insulating medium with a higher dielectric constant, the antenna size is reduced to a certain extent, while also increasing its concealment and protection, making it suitable for platform applications. In dielectric-buried antennas, when analyzing the impedance and radiation characteristics of the antenna, the effect of introducing the dielectric is considered, typically by introducing an equivalent dielectric constant ε. e The concept of is expressed as:

[0036] ε e =1+q(ε r -1) (4)

[0037] In the formula, q is the filling factor. When completely filled in the medium, q = 1; when completely filled in air, q = 0; and when it is between the two, 0 < q < 1. r Let q be the relative permittivity of the dielectric substrate. Therefore, for an antenna fully buried in the dielectric, q = 1. Thus, the equivalent permittivity and the relative permittivity are approximately equal. For this, the electromagnetic wave wavelength λ in a dielectric-buried antenna... g The calculation formula is: In the formula, c is the speed of light in a vacuum, and f0 is the center frequency of the antenna.

[0038] The size of the antenna is related to the wavelength. Compared with an antenna in free space, when the relative permittivity is greater than 1, the size of the antenna can be reduced, thus achieving the goal of antenna miniaturization. In the present invention, due to the adoption of the local dielectric embedding method, the equivalent permittivity is more complex. According to the required antenna size, the thickness, height and relative permittivity of the loaded dielectric block need to be comprehensively considered, and the expected parameter values are obtained by full-wave electromagnetic simulation calculation. At the same time, due to the local dielectric loading, the loaded dielectric substrate is truncated at a certain height. In order to reduce the reflection of electromagnetic waves, non-conductive through-hole arrays are etched on the loaded dielectric substrate, which plays a role in adjusting the impedance and radiation characteristics. The structure is as shown in Figure 3 (d). Through local dielectric embedding and lumped line resistance loading, the printed log-periodic antenna designed in the present invention can achieve the compression of the horizontal size of the antenna.

[0039] In the present invention, the polarization port 2 adopts a single-ridge ultra-wideband open-ended horn antenna radiator. The single-ridge horn antenna designed in the present invention is realized based on the mirror principle of electromagnetic waves, and theoretically can effectively reduce the size of the antenna. The horn antenna has the characteristics of simple structure, large power capacity, wide frequency band, easy control of the radiation pattern, etc., and is widely used in electromagnetic compatibility testing, radar and communication systems. The structure of the single-ridge ultra-wideband open-ended horn antenna radiator designed in the present invention is as shown in Figure 2 , and its structure includes a metal ridge in the shape of an exponential curve, a metal reflection floor that acts as a mirror, a metal resonant cavity for feeding, a coaxial port and a probe for feeding. When designing the ridge curve, the contour of the ridge is reasonably selected to achieve good transmission and radiation characteristics. In the ridge horn section, the ridge curve adopts the exponential curve form:

[0040]

[0041] where: 0 < z < h_horn, h_horn is the height of the micro horn, z is the coordinate of the horn central axis, and the values of A1, B1, and C1 are undetermined coefficients, which are determined according to the required size of the horn antenna.

[0042] The width of the feeding resonant cavity of the horn antenna is a, and the length is h_cavity. In order to improve the impedance matching effect of the horn antenna and reduce the standing wave, the resonant cavity of the antenna adopts a tapered cavity. In the design of the metal reflection floor, the present invention adopts the structure shown in Figure 2 (d), and adjusts the parameters nn1, nn2, mm1 and mm2 to achieve the goal of adjusting the impedance of the radiation pattern of the horn antenna. The single-ridge ultra-wideband horn antenna and the printed log-periodic antenna are configured according to the structure shown in Figure 1 to achieve effective isolation and polarization diversity effect of the two polarization ports.

[0043] Example:

[0044] This example proposes a miniaturized polarized diversity antenna device based on a single-ridge horn and a log-periodic antenna. The antenna's performance was simulated and optimized using full-wave electromagnetic simulation technology. The simulation results verify the feasibility of the miniaturized polarized diversity antenna based on a single-ridge horn and a log-periodic antenna proposed in this invention.

[0045] The circuit characteristics of a miniaturized polarization diversity antenna based on a single-ridge horn and a log-periodic antenna designed in this invention are as follows: Figure 6 As shown in the figure, when the operating frequencies are 1.7GHz, 2.3GHz, 3GHz, 4GHz, and 5GHz, the VSWR of polarization port 1 of the antenna is approximately 4.39, 1.49, 1.06, 1.12, and 1.67, respectively, and the VSWR of polarization port 2 is approximately 2.94, 2.27, 1.94, 1.87, and 1.37, respectively. The port isolation is approximately 40.97dB, 26.63dB, 36.64dB, 49.31dB, and 39.30dB, respectively.

[0046] Figures 7 to 12 Simulation results of the radiation patterns of the two polarized ports at operating frequencies of 1.7 GHz, 2.3 GHz, 3 GHz, 4 GHz, and 5 GHz are presented. For each polarized port at each frequency, the three-dimensional gain pattern, three-dimensional axial ratio pattern, gain pattern in the xoz plane, and gain pattern in the yoz plane are given. For polarized port 1, at operating frequencies of 1.7 GHz, 2.3 GHz, 3 GHz, 4 GHz, and 5 GHz, the antenna gains are approximately 2.09 dB, 5.27 dB, 5.33 dB, 5.91 dB, and 5.81 dB, respectively; the axial ratios in the main radiation direction are approximately greater than 40 dB, 38.66 dB, 31.74 dB, 34.59 dB, and 26.59 dB, respectively. For polarization port 2, at operating frequencies of 1.7 GHz, 2.3 GHz, 3 GHz, 4 GHz, and 5 GHz, the antenna gain is approximately 2.02 dB, 2.16 dB, 3.07 dB, 4.69 dB, and 5.63 dB, respectively, and the axial ratios in the main radiation direction are approximately greater than 40 dB, greater than 40 dB, 30.01 dB, 28.42 dB, and greater than 40 dB, respectively.

[0047] In summary, this invention proposes a design scheme and antenna structure device for a miniaturized polarized diversity antenna based on a single-ridge horn and a log-periodic antenna. This antenna device employs a combined miniaturized broadband antenna structure to achieve horizontal and vertical polarized diversity operation modes. The antenna's two polarization ports are a single-ridge horn open horn antenna radiator and a partially buried printed log-periodic antenna radiator. By rationally configuring the positions between the single-ridge horn open horn antenna radiator and the partially buried printed log-periodic antenna radiator, good polarization isolation and cross-polarization performance are achieved. Based on the electromagnetic field mirror principle, a single-ridge horn antenna is used to compress the antenna size; by optimizing the design of the single-ridge horn antenna's reflector ground structure and shape, the impedance and radiation pattern performance of the single-ridge horn antenna are adjusted. The polarized diversity antenna scheme designed in this invention is simple in design, easy to manufacture and assemble, and has low cost, making it beneficial for engineering applications. The miniaturized polarized diversity antenna device based on a single-ridge horn and a log-periodic antenna designed in this invention is suitable for application in dual-polarized radar systems, electronic countermeasures systems, and wireless communication systems, and has significant application value.

Claims

1. A miniaturized broadband polarized antenna based on a single-ridge horn and a log-periodic antenna, characterized in that, A dual-polarization diversity method including vertical polarization and horizontal polarization, where the electromagnetic fields of the two polarization ports are orthogonal in the far radiation region. Among them, polarization port one uses a miniaturized printed log-periodic antenna with local dielectric burial, and polarization port two uses a single-ridge ultra-wideband horn antenna; in the printed log-periodic antenna, the printed oscillators are printed on a microwave dielectric substrate according to a periodic law. Let the longest oscillator at the low-frequency end, that is, the length of the first printed oscillator be 2L1, the oscillator width be W1, and the distance between the first oscillator and the second oscillator be d1. According to the periodic law, the structure of the printed log-periodic antenna satisfies the following formula: L n+1 / L n =τ1(1), W n+1 / W n =τ2(2),d n+1 / d n =τ2(3), where τ1, τ1 and τ1 are periodic laws. The three parameters are adjusted separately to jointly optimize the electrical performance of the printed log-periodic antenna. At low frequencies, in order to reduce electromagnetic wave reflection and improve impedance matching performance, a wave-absorbing resistor is loaded at the end of the antenna feed line to effectively reduce the voltage standing wave ratio of the printed log-periodic antenna. In order to improve the radiation efficiency and impedance matching performance of the antenna, a high dielectric constant dielectric substrate is loaded on both sides of the dielectric substrate of the printed log-periodic antenna at the position corresponding to the low-frequency vibrator, while the situation at the high-frequency position remains unchanged, so as to achieve the goal of adjusting the radiation performance of the printed log-periodic antenna. Considering the influence of the introduction of the dielectric, an equivalent dielectric constant ε is introduced. e The concept is determined by the following formula: ε e =1+q(ε r -1)(4), where q is the filling factor. When completely filled in the medium, q = 1; when completely filled in air, q = 0; and when between the two, 0 < q < 1. r Let q be the relative permittivity of the dielectric substrate. For an antenna fully buried in the dielectric, q = 1, therefore the equivalent permittivity and the relative permittivity are approximately equal. The wavelength λ of the electromagnetic wave in the dielectric-buried antenna is... g The calculation formula is: In the formula, c is the speed of light in a vacuum, and f0 is the center frequency of the antenna; The second polarization port employs a single-ridge ultra-wideband horn antenna with a single-ridge ultra-wideband open horn antenna radiator, including an exponentially shaped metal ridge, a metal reflector ground that acts as a mirror, a metal resonant cavity for feeding, and a coaxial cable port and probe for feeding. In the horn section, the ridge curve adopts an exponential curve form as follows: In the formula: 0 < z < h_horn, h_horn is the height of the micro-horn, and z is the coordinate of the horn central axis.

2. The miniaturized broadband polarized antenna based on a single-ridge horn and a log-periodic antenna according to claim 1, characterized in that, The antenna of polarization port one etches a non-conductive via array on the loaded dielectric substrate, which plays a role in adjusting impedance and radiation characteristics. Through local dielectric burial and collective line resistance loading, the horizontal size of the antenna is compressed.

3. A miniaturized broadband polarized antenna based on a single-ridge horn and a log-periodic antenna according to claim 1, characterized in that, The width of the feed resonant cavity of the horn antenna of polarization port two is a, and the length is h_cavity. In order to improve the impedance matching effect of the horn antenna and reduce the standing wave, the resonant cavity of the antenna uses a tapered cavity.

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