Double-frequency microstrip circulator based on multi-layer material nesting

Abstract

The invention belongs to the field of microwave communication, and relates to a double-frequency microstrip circulator based on multi-layer material nesting, and the circulator comprises a substrate, a magnetic conductive sheet, a high dielectric ceramic, a high dielectric constant ferrite ring, a high magnetic saturation ferrite, a circuit layer, a ceramic sheet, and a permanent magnet. The magnetic conductive sheet is arranged at the bottom of the base body, the high-dielectric ceramic is arranged on the magnetic conductive sheet, the high-dielectric-constant ferrite ring is annularly embedded in the high-dielectric-constant ceramic, and the high-magnetic-saturation ferrite is embedded in the high-dielectric-constant ferrite ring. The circuit layer is arranged on the substrate consisting of the high dielectric ceramic, the high dielectric constant ferrite ring and the high magnetic saturation ferrite, the ceramic chip is arranged on the circuit layer, and the permanent magnet is arranged on the ceramic chip. The overall size is small, weight is light, and reliability is high; the working frequency range is wide, through different transformations, the system is not easily detected by enemies, the confidentiality is high, and the anti-interference capability is strong; the method can be widely applied to the fields of mobile communication, satellite communication, radar detection, electronic countermeasures and the like.

Description

Technical Field

[0001] The invention relates to the technical field of microwave communications, and in particular to a double-frequency microstrip circulator based on multi-layer material nesting. Background Art

[0002] The circulator is also called a circulator. Its outstanding feature is the unidirectional transmission of high-frequency signal energy. It controls the electromagnetic wave to be transmitted along a certain circular direction. This unidirectional transmission of high-frequency signal energy is mostly used between the output end and the load of a high-frequency power amplifier to play the role of being independent and isolated from each other. The load impedance does not affect the working state of the power amplifier when it changes or even when it is open or short-circuited, thereby protecting the power amplifier.

[0003] In modern microwave communication systems, circulators, as key components, undertake the important task of guiding microwave signals to circulate and propagate along a specific path to prevent signal interference and damage. With the rapid development of communication technology, the performance requirements for circulators are increasing, especially in terms of bandwidth, insertion loss, reverse isolation, and miniaturization.

[0004] Microstrip circulators are core components in microwave communication equipment, and their performance directly affects the operating efficiency and reliability of the entire system. Traditional microstrip circulators mostly use single-layer or simple stacking structures, which are difficult to meet the requirements of high frequency, broadband, low loss and miniaturization. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a double frequency microstrip circulator based on nested multi-layer materials, which adopts the following technical solution, including: A substrate, a magnetic conductive sheet, a high dielectric ceramic, a high dielectric constant ferrite ring, a high magnetic saturation ferrite, a circuit layer, a ceramic sheet, and a permanent magnet; wherein the magnetic conductive sheet is arranged at the bottom of the substrate, the high dielectric ceramic is arranged on the magnetic conductive sheet, the high dielectric constant ferrite ring is annularly embedded in the high dielectric ceramic, the high magnetic saturation ferrite is embedded in the high dielectric constant ferrite ring, the circuit layer is arranged on the substrate composed of the high dielectric ceramic, the high dielectric constant ferrite ring and the high magnetic saturation ferrite, the ceramic sheet is arranged on the circuit layer, and the permanent magnet is arranged on the ceramic sheet.

[0006] Preferably, the substrate is made of non-magnetic material.

[0007] Preferably, the magnetic conductive sheet is made of industrial pure iron or cold-rolled steel plate and is processed and gold-plated.

[0008] Preferably, the circuit layer comprises a microstrip circuit.

[0009] Preferably, the dielectric constant of the high dielectric constant ferrite ring is 28.

[0010] Preferably, the circulator length d1 is 5 to 9 mm, the circulator width d2 is 5 to 9 mm, and the circulator height d3 is 1.5 to 3.5 mm.

[0011] Preferably, the circulator length d1 is 7 mm, the circulator width d2 is 7 mm, and the circulator height d3 is 2.5 mm.

[0012] Preferably, the magnetic conductive sheet is square or rectangular.

[0013] Preferably, the magnetic conductive sheet is fixed to the substrate by welding or bonding.

[0014] Preferably, the high dielectric ceramic is disposed on the magnetic conductive sheet by pressing or sintering.

[0015] Compared with the prior art, the present invention mainly has the following beneficial effects: by arranging a substrate, a magnetic conductive sheet, a high dielectric ceramic, a high dielectric constant ferrite ring, a high magnetic saturation ferrite, a circuit layer, a ceramic sheet, and a permanent magnet; wherein the magnetic conductive sheet is arranged at the bottom of the substrate, the high dielectric ceramic is arranged on the magnetic conductive sheet, the high dielectric constant ferrite ring is embedded in the high dielectric ceramic, the high magnetic saturation ferrite is embedded in the high dielectric constant ferrite ring, the circuit layer is arranged on the substrate composed of the high dielectric ceramic, the high dielectric constant ferrite ring and the high magnetic saturation ferrite, the ceramic sheet is arranged on the circuit layer, and the permanent magnet is arranged on the ceramic sheet; the overall volume is small, the weight is light, and the reliability is high. It can be used in airborne phased array radars, missile-borne radars and other systems to reduce the overall weight; the operating frequency range is wide, and it is not easy to be detected by the enemy through different transformations, and it has high confidentiality and strong anti-interference ability; it can be widely used in mobile communications, satellite communications, radar detection, electronic countermeasures and other fields, especially in 5G communications, Internet of Things, intelligent driving and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the scheme in the present invention, a brief introduction is given below to the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 It is a schematic diagram of the exploded structure of the double frequency microstrip circulator based on nesting of multiple layers of materials of the present invention; Figure 2 It is a schematic diagram of the three-dimensional structure of the double frequency microstrip circulator based on the nesting of multiple layers of materials of the present invention; Figure 3It is a schematic diagram of the top view of the structure of the double frequency microstrip circulator based on nesting of multiple layers of materials of the present invention; Figure 4 It is a side structural schematic diagram of the double frequency microstrip circulator based on nesting of multiple layers of materials of the present invention.

[0018] Figure numerals: 1-magnetic conductive sheet, 2-high dielectric ceramic, 3-high dielectric constant ferrite ring, 4-high magnetic saturation ferrite, 5-circuit layer, 6-ceramic sheet, 7-permanent magnet. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0021] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0022] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings.

[0023] Figure 1 It is a schematic diagram of the exploded structure of the double frequency microstrip circulator based on nesting of multiple layers of materials of the present invention; Figure 2 It is a schematic diagram of the three-dimensional structure of the double frequency microstrip circulator based on the nesting of multiple layers of materials of the present invention; Figure 3 It is a schematic diagram of the top view of the structure of the double frequency microstrip circulator based on nesting of multiple layers of materials of the present invention; Figure 4This is a side view of the structure of the double frequency microstrip circulator based on multi-layer material nesting of the present invention. Please refer to Figure 1 to Figure 4 The double frequency microstrip circulator based on nested multilayer materials includes: a substrate, a magnetic conductive sheet 1, a high dielectric ceramic 2, a high dielectric constant ferrite ring 3, a high magnetic saturation ferrite 4, a circuit layer 5, a ceramic sheet 6, and a permanent magnet 7; wherein the magnetic conductive sheet 1 is arranged at the bottom of the substrate, the high dielectric ceramic 2 is arranged on the magnetic conductive sheet 1, the high dielectric constant ferrite ring 3 is embedded in the high dielectric constant ceramic 2, the high magnetic saturation ferrite 4 is embedded in the high dielectric constant ferrite ring 3, the circuit layer 5 is arranged on the substrate composed of the high dielectric ceramic 2, the high dielectric constant ferrite ring 3 and the high magnetic saturation ferrite 4, the ceramic sheet 6 is arranged on the circuit layer 5, and the permanent magnet 7 is arranged on the ceramic sheet 6.

[0024] The substrate is the supporting structure of the circulator of this embodiment and can be made of non-magnetic materials. The shape of the substrate can be set according to actual needs. It is made into a certain shape and size through precision machining to provide a stable supporting platform for subsequent material layers. In this embodiment, the substrate is set as a rectangular parallelepiped.

[0025] The magnetic conductive sheet 1 is used to guide the distribution of the magnetic field and improve the utilization rate of the magnetic field. The magnetic conductive sheet 1 is located at the core of the circulator and can be made of materials with high magnetic permeability such as industrial pure iron or cold-rolled steel plates, etc., which are processed and gold-plated. The main function of the magnetic conductive sheet 1 is to guide and concentrate the magnetic field, so that the magnetic field distribution in the circulator is more uniform, thereby improving the performance of the circulator. The magnetic conductive sheet 1 can be fixed to the substrate by welding or bonding. In specific implementation, the magnetic conductive sheet 1 can be, but is not limited to, square or rectangular. In this embodiment, the magnetic conductive sheet 1 is set to be square.

[0026] The high dielectric ceramic 2, as the insulating and supporting material between the circuit layer 5 and the high magnetic saturation ferrite 4, has excellent dielectric properties and mechanical strength. Its high dielectric constant helps to reduce the circuit size and improve the integration.

[0027] Ferrite gyromagnetism with a magnetic saturation of about 2800Gs basically responds in the X-band and Ku-band, and the material with 1800Gs mainly responds in the C-band. However, since the frequency of the C-band is relatively low and the wavelength is relatively long, the required capacitance and inductance are larger. Therefore, this embodiment selects a high magnetic saturation ferrite 4 material with a dielectric constant of 28, which is twice that of conventional materials, effectively reducing the size of the product.

[0028] As one of the core functional materials of the circulator of this embodiment, the high dielectric constant ferrite ring 3 not only provides the necessary magnetic permeability, but also optimizes the transmission characteristics of microwave signals through its high dielectric properties. The high dielectric constant ceramic 2 is arranged on the magnetic conductive sheet 1 by pressing or sintering.

[0029] Circuit layer 5 is responsible for signal transmission and processing. It should be noted that the design of circuit layer 5 needs to consider signal transmission efficiency, impedance matching and compatibility with other material layers. Circuit layer 5 includes a microstrip circuit. In order to meet the requirements of operating frequency and miniaturization, the center junction of the microstrip circuit of circuit layer 5 is made as large as possible, distributed on a ferrite gyromagnet with high magnetic saturation intensity and high dielectric constant, and the port resonant circuit is placed on a ceramic substrate. A multi-stage matching method is adopted to change the impedance corresponding to the response characteristics of different bands. Through simulation and optimization, better electrical performance is achieved.

[0030] In specific implementation, the circulator length d1 of this embodiment can be 5-9 mm, the circulator width d2 can be 5-9 mm, and the circulator height d3 can be 1.5-3.5 mm. Preferably, the circulator length d1 is set to 7 mm, the circulator width d2 is set to 7 mm, and the circulator height d3 is 2.5 mm. This makes the overall structure of the circulator of this embodiment compact, small in size, and light in weight.

[0031] The ceramic sheet 6 plays a supporting and protective role in the circulator, and also helps to optimize the transmission characteristics of the microwave signal. The ceramic sheet 6 is usually made of high-purity, low-loss ceramic material, and has excellent mechanical properties and thermal stability. The ceramic sheet 6 serves as an isolation layer between the circuit layer 5 and the permanent magnet 7 to prevent the magnetic field from directly acting on the circuit layer 5 and causing interference. At the same time, the ceramic sheet 6 also has a certain heat dissipation function, which helps to maintain the stable operation of the circulator of this embodiment. The ceramic sheet 6 is tightly combined with the substrate or other material layers through precision machining and sintering processes to form a stable overall structure.

[0032] Permanent magnet 7 is a key component that provides a bias magnetic field in the circulator. The magnetic field direction of permanent magnet 7 is perpendicular to the microwave signal transmission direction in the circulator, and the circular transmission of the signal is achieved by changing the magnetic permeability of the microwave signal. Permanent magnet 7 provides a stable bias magnetic field, allowing the circulator to work normally without an external power supply. The position and strength of permanent magnet 7 need to be adjusted according to the specific design of the circulator to ensure the best magnetic field distribution and performance. Permanent magnet 7 is made into a certain shape and magnetic field strength through precision machining and magnetization process, and can be fixed on the ceramic sheet 6 of the circulator by mechanical or bonding methods.

[0033] The working principle of the circulator in this embodiment is: When a microwave signal is input from a port of the circulator, the signal is first transmitted through the microstrip circuit in the circuit layer. During the transmission process, the signal is deflected by the bias magnetic field generated by the permanent magnet. The direction and intensity of the bias magnetic field determine the direction and degree of the signal deflection. At the same time, the magnetic sheet and high magnetic saturation ferrite work together to guide the magnetic field to form a stable distribution pattern inside the circulator.

[0034] To achieve double frequency operation, high dielectric constant ferrite rings and high magnetic saturation ferrites have excellent dielectric and magnetic properties, respectively, and can provide stable magnetic permeability and dielectric constant in different frequency bands. By optimizing the ratio and layout of these two materials, the circulator can maintain a high performance level in both low frequency bands (such as 5-13 GHz) and high frequency bands (such as 10-26 GHz). The operating frequency covers C band, X band, and Ku band, with double frequency bandwidth.

[0035] Specifically, when working in the low frequency band, the dielectric properties of the high dielectric constant ferrite ring are mainly used to optimize the signal transmission characteristics; while when working in the high frequency band, it relies more on the magnetic properties of the high magnetic saturation ferrite to improve the signal isolation and directionality. At the same time, by adjusting the strength and position of the permanent magnet and the design parameters of the circuit layer (such as the width, length and spacing of the microstrip line), the performance of the circulator in different frequency bands can be further optimized.

[0036] Another important function of the circulator in this embodiment is to provide reverse isolation, that is, to prevent the signal from being output from an undesired port. This function is mainly achieved through magnetic field guidance and signal deflection. When a signal is input from a certain port and transmitted along a specific path, due to the effect of the magnetic field and the limitation of the circuit structure, the signal cannot be directly transmitted to an undesired port. Even if part of the signal leaks to the vicinity of the undesired port, it will be suppressed by the strong reverse isolation, thereby ensuring the purity of the signal and the stability of the system.

[0037] Because the passband frequency span is large, the resonance frequency of ferrite gyromagnetic materials is basically determined by their inherent characteristics due to magnetic saturation intensity, line width and spin characteristics, so the frequency requirement of large bandwidth cannot be achieved by using a single ferrite gyromagnetic material. This embodiment uses ferrite gyromagnetic materials with different magnetic saturation intensities and different dielectric constants to nest and resonate the center node frequency, and uses high dielectric ceramics to match the impedance of the port on the periphery. Through this composite material model, the required frequency bandwidth is achieved.

[0038] The implementation of this embodiment has the following beneficial effects: by arranging a substrate, a magnetic conductive sheet, a high dielectric ceramic, a high dielectric constant ferrite ring, a high magnetic saturation ferrite, a circuit layer, a ceramic sheet, and a permanent magnet; wherein the magnetic conductive sheet is arranged at the bottom of the substrate, the high dielectric ceramic is arranged on the magnetic conductive sheet, the high dielectric constant ferrite ring is embedded in the high dielectric ceramic, the high magnetic saturation ferrite is embedded in the high dielectric constant ferrite ring, the circuit layer is arranged on the substrate composed of the high dielectric ceramic, the high dielectric constant ferrite ring and the high magnetic saturation ferrite, the ceramic sheet is arranged on the circuit layer, and the permanent magnet is arranged on the ceramic sheet; the overall volume is small, the weight is light, and the reliability is high. It can be used in airborne phased array radar, missile-borne radar and other systems to reduce the overall weight; the operating frequency range is wide, and it is not easy to be detected by the enemy through different transformations, and it has high confidentiality and strong anti-interference ability; it can be widely used in mobile communications, satellite communications, radar detection, electronic countermeasures and other fields, especially in 5G communications, Internet of Things, intelligent driving and other fields.

[0039] The present invention is described with reference to specific embodiments, but it should be understood by those skilled in the art that various changes and equivalent substitutions may be made without departing from the scope of the present invention. In addition, in order to adapt to specific occasions of the present invention, the present invention may be modified in many ways without departing from its scope of protection. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all embodiments falling within the scope of protection of the claims.

Claims

1. A double frequency microstrip circulator based on multi-layer material nesting, characterized in that: include: A substrate, a magnetic conductive sheet, a high dielectric ceramic, a high dielectric constant ferrite ring, a high magnetic saturation ferrite, a circuit layer, a ceramic sheet, and a permanent magnet; wherein the magnetic conductive sheet is arranged at the bottom of the substrate, the high dielectric ceramic is arranged on the magnetic conductive sheet, the high dielectric constant ferrite ring is annularly embedded in the high dielectric ceramic, the high magnetic saturation ferrite is embedded in the high dielectric constant ferrite ring, the circuit layer is arranged on the substrate composed of the high dielectric ceramic, the high dielectric constant ferrite ring and the high magnetic saturation ferrite, the ceramic sheet is arranged on the circuit layer, and the permanent magnet is arranged on the ceramic sheet.

2. The double frequency microstrip circulator based on multi-layer material nesting according to claim 1, characterized in that: The substrate is made of non-magnetic material.

3. The double frequency microstrip circulator based on multi-layer material nesting according to claim 1, characterized in that: The magnetic conductive sheet is made of industrial pure iron or cold-rolled steel plate and is processed and gold-plated.

4. The double frequency microstrip circulator based on multi-layer material nesting according to claim 1, characterized in that: The circuit layer includes a microstrip circuit.

5. The double frequency microstrip circulator based on nested multi-layer materials according to claim 1, characterized in that: The dielectric constant of the high dielectric constant ferrite ring is 28.

6. The double frequency microstrip circulator based on multi-layer material nesting according to any one of claims 1 to 5, characterized in that: The circulator length d1 is 5 to 9 mm, the circulator width d2 is 5 to 9 mm, and the circulator height d3 is 1.5 to 3.5 mm.

7. The double frequency microstrip circulator based on nested multi-layer materials according to claim 6, characterized in that: The circulator length d1 is 7 mm, the circulator width d2 is 7 mm, and the circulator height d3 is 2.5 mm.

8. The double frequency microstrip circulator based on nested multi-layer materials according to claim 6, characterized in that: The magnetic conductive sheet is square or rectangular.

9. The double frequency microstrip circulator based on nested multi-layer materials according to claim 6, characterized in that: The magnetic conductive sheet is fixed on the base by welding.

10. The double frequency microstrip circulator based on multi-layer material nesting according to claim 6, characterized in that: The high dielectric ceramic is arranged on the magnetic conductive sheet by pressing or sintering.

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