Microstrip circulator

Abstract

A microstrip circulator provided by the present invention comprises an alloy bottom plate, a substrate, an aluminum oxide ceramic chip, a permanent magnet and a microstrip circuit, the substrate is internally provided with a ceramic chip and an ion-doped ferrite chip, the ferrite chip is embedded on the ceramic chip, the substrate is installed on the alloy bottom plate, and the permanent magnet is installed on the substrate. The aluminum oxide ceramic chip and the microstrip circuit are both installed on the substrate, and the permanent magnet is installed on the aluminum oxide ceramic chip. The power bearing capacity of the ferrite material is regulated and controlled through ion doping, and meanwhile, the ceramic material with high power bearing capacity is adopted as a part of the substrate, so that the power bearing capacity of the microstrip circulator is essentially improved. The microwave power divider has the advantages of high power, wide band, low loss and the like, can meet the performance requirements of users on excellent electrical performance indexes and high power resistance, and is suitable for high-performance microwave integrated circuits. The problem that the microstrip circulator is poor in power bearing capacity is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of microwave devices, in particular to a microstrip circulator. BACKGROUND

[0002] The circulator can realize microwave signal transmission and reception at the same time, and isolate the reverse transmission of microwave signals in the microwave transceiver system, thereby stabilizing and protecting the microwave transmission circuit. The microstrip circulator is widely used in radar, microwave communication and microwave measurement due to its planar and small size.

[0003] With the rapid development of radar systems, higher power capacity is required for microwave components on the basis of high integration and miniaturization. However, compared with other large volume devices of the same type, the microstrip circulator is obviously at a disadvantage in terms of power due to its small size and planar design. The power bearing capacity of the microstrip circulator is limited by the inherent properties of the ferrite material. At present, the microstrip circulator is designed using undoped full ferrite substrate, and its power bearing capacity is low.

[0004] Therefore, in view of the urgent demand for high power and miniaturization of microwave components, the design of the existing microstrip circulator needs to be improved to further improve its power bearing capacity. SUMMARY

[0005] The technical problem solved by the present application is to provide a microstrip circulator to overcome the shortcomings of the prior art.

[0006] The technical solution for solving the above technical problem is as follows: a microstrip circulator, comprising: an alloy base plate, a substrate, an alumina ceramic sheet, a permanent magnet and a microstrip circuit, the substrate is provided with a ceramic sheet and an ion-doped ferrite sheet, the ferrite sheet is embedded on the ceramic sheet, the substrate is installed on the alloy base plate, the alumina ceramic sheet and the microstrip circuit are installed on the substrate, and the permanent magnet is installed on the alumina ceramic sheet.

[0007] The beneficial effects of the technical solution of the present application are: by ion doping to control the power bearing capacity of the ferrite material, and by using a ceramic material with high power bearing capacity as part of the substrate, the power bearing capacity of the microstrip circulator is essentially improved. It has the advantages of high power, wide band and low loss, can meet the performance requirements of excellent electrical performance indicators and high power resistance, and is suitable for high-performance microwave integrated circuits. The problem of poor power bearing capacity of the microstrip circulator is solved.

[0008] Further, the microstrip circuit is a disc junction circuit, the middle part of the microstrip circuit covers the ferrite sheet, and the microstrip circuit is connected with a plurality of transmission microstrip lines; the width of the transmission microstrip line is not less than a predetermined value.

[0009] The beneficial effects of the further technical solutions are: the disc junction circuit is adopted, the area of the center junction circuit completely covers the ferrite disc in the middle of the substrate, the line width of the microstrip circuit is controlled as wide as possible on the basis of ensuring the performance index, and the power bearing capacity of the circulator is further improved.

[0010] Further, the plurality of transmission microstrip lines are three impedance matching transmission microstrip lines intersecting at 120°, the plurality of transmission microstrip lines are located on the ceramic sheet, and the port matching transmission lines are respectively connected to the plurality of transmission microstrip lines. The width of the transmission microstrip line outside the port matching transmission line located on the ceramic sheet is not less than a preset value, and the preset value is 0.45 mm.

[0011] The beneficial effects of the further technical solutions are: the disc junction circuit is adopted, the area of the center junction circuit completely covers the ferrite disc in the middle of the substrate, the line width of the microstrip circuit is controlled as wide as possible on the basis of ensuring the performance index, and the power bearing capacity of the circulator is further improved. By adopting ion-doped ferrite material and designing a suitable microstrip circuit pattern, the power bearing capacity of the circulator is improved, and the circulator has advantages of high power, wide band, low loss, etc., can meet the performance requirements of excellent electrical performance index and high power resistance of users, and is suitable for high-performance microwave integrated circuits.

[0012] Further, the ceramic sheet is a square ceramic sheet, the ferrite disc is a ferrite disc, and the ferrite disc is embedded in the middle of the ceramic sheet; the alumina ceramic sheet is a circular structure.

[0013] The beneficial effects of the further technical solutions are: the ion-doped ferrite disc and the square ceramic sheet are combined together as the substrate of the microstrip circulator, the power bearing capacity of the ferrite material is regulated by ion doping, and at the same time, the ceramic material with high power bearing capacity is used as part of the substrate, which essentially improves the power bearing capacity of the microstrip circulator.

[0014] Further, the ceramic sheet is made of ceramic material with a dielectric constant of 10-50; the ferrite disc is made of cobalt ion-doped garnet and spinel ferrite material; the alumina ceramic sheet is made of ceramic material with a dielectric constant of 2-10; and the alloy bottom plate is made of magnetic metal, and the permanent magnet is a samarium-cobalt permanent magnet.

[0015] The beneficial effects of the further technical solutions are: the power bearing capacity of the ferrite material is regulated by ion doping, and at the same time, the ceramic material with high power bearing capacity is used as part of the substrate, which essentially improves the power bearing capacity of the microstrip circulator.

[0016] Further, the microstrip circuit is prepared on the surface of the substrate by a process of electroplating, sputtering, photolithography and etching.

[0017] The beneficial effects of the above further technical solutions are that the metal layer of the microstrip circuit bottom layer is prepared by electroplating, the surface gold layer is prepared by magnetron sputtering, the microstrip circuit pattern plate is made by a photolithography machine, and the high-precision microstrip circuit pattern is prepared on the surface of the substrate by chemical etching.

[0018] Further, the alloy bottom plate is welded with the lower surface of the substrate, the ferrite sheet is embedded on the ceramic sheet by gluing or co-firing, the lower surface of the alumina ceramic sheet is fixedly connected with the microstrip circuit on the upper surface of the substrate by gluing, and the lower surface of the permanent magnet is fixedly connected with the upper surface of the alumina ceramic sheet by gluing.

[0019] The beneficial effects of the above further technical solutions are that the permanent magnet is a samarium-cobalt permanent magnet, and the permanent magnet and the alumina ceramic sheet are bonded together by epoxy glue to provide a uniform magnetic field.

[0020] Further, the lower surface of the permanent magnet is fixedly connected with the upper surface of the alumina ceramic sheet by gluing with epoxy glue.

[0021] The beneficial effects of the above further technical solutions are that the permanent magnet is a samarium-cobalt permanent magnet, and the permanent magnet and the alumina ceramic sheet are bonded together by epoxy glue to provide a uniform magnetic field.

[0022] Further, the dielectric constant of the ceramic sheet is 21, the dielectric constant of the ferrite sheet is 14, the saturation magnetization of the ferrite sheet is 3200Gs, and the dielectric constant of the alumina ceramic sheet is 8.6.

[0023] The beneficial effects of the above further technical solutions are that the dielectric constant and the saturation magnetization of each component are controlled to ensure performance indicators.

[0024] Further, the surface of the alloy bottom plate is plated with silver, the thickness of the alloy bottom plate is 0.3mm, the thickness of the substrate is 0.5mm, and the diameter of the ferrite sheet is 3mm.

[0025] The beneficial effects of the above further technical solutions are that the size of each component is controlled to ensure high integration and miniaturization.

[0026] The advantages of the additional aspects of the present application will be partially given in the following description, partially will become apparent from the following description, or will be understood by those skilled in the art through the practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0028] Figure 1 Structure schematic diagram of the microstrip circulator provided by the embodiment of the present application.

[0029] Figure 2 Structure schematic diagram of the microstrip circulator provided by the embodiment of the present application.

[0030] Figure 3 Structure schematic diagram of the microstrip circulator provided by the embodiment of the present application.

[0031] Explanation of the reference numerals: 1, alloy bottom plate; 2, substrate; 3, alumina ceramic sheet; 4, permanent magnet; 5, ceramic sheet; 6, ferrite sheet; 7, microstrip circuit. DETAILED DESCRIPTION

[0032] The principles and features of the present application will be described below in conjunction with the drawings, and the embodiments shown are only used to explain the present application, and are not used to limit the scope of the present application.

[0033] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the following will combine the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, and not all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of the present application.

[0035] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0036] In the description of the embodiments of the present application, it should be noted that if the terms "upper", "lower", "horizontal", "inner" and the like indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, or the orientation or position relationship when the product of the present application is usually placed, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0037] In the description of the embodiments of the present application, it should be noted that unless otherwise explicitly specified and limited, if the terms "arrangement", "installation", "connection", "connection" appear, they should be understood in a broad sense, for example, they can be fixedly connected, or can be detachably connected, or integrally connected, can be mechanically connected, or can be electrically connected, can be directly connected, or indirectly connected through an intermediate medium, or can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0038] As shown in Figures 1 to 3 The embodiment of the present application provides a microstrip circulator, which comprises an alloy base plate 1, a substrate 2, an alumina ceramic sheet 3, a permanent magnet 4 and a microstrip circuit 7, the substrate 2 is provided with a ceramic sheet 5 and an ion-doped ferrite sheet 6, the ferrite sheet 6 is embedded on the ceramic sheet 5, the substrate 2 is installed on the alloy base plate 1, the alumina ceramic sheet 3 and the microstrip circuit 7 are both installed on the substrate 2, and the permanent magnet 4 is installed on the alumina ceramic sheet 3.

[0039] The beneficial effects of the technical scheme of the present application are: the power bearing capacity of the ferrite material is adjusted and controlled by ion doping, and at the same time, the ceramic material with high power bearing capacity is used as part of the substrate, which essentially improves the power bearing capacity of the microstrip circulator. It has the advantages of high power, wide band and low loss, can meet the performance requirements of excellent electrical performance indicators and high power resistance, and is suitable for high-performance microwave integrated circuits. The problem of poor power bearing capacity of the microstrip circulator is solved.

[0040] The microstrip circulator provided by the embodiment of the present application can be a high-power microstrip circulator, which comprises an alloy base plate 1, a substrate 2, an alumina ceramic sheet 3 and a permanent magnet 4.

[0041] Further, the alloy base plate 1 is made of a magnetic metal material.

[0042] Further, the square ceramic piece (ceramic piece 5) in the substrate 2 is a ceramic material with a dielectric constant of 10-50, and the ferrite round piece (ferrite piece 6) is an ion-doped garnet, spinel ferrite material.

[0043] Further, the microstrip circuit 7 is a disc junction circuit, connected by a center disc completely covering the ferrite round piece (ferrite piece 6) and three intersecting 120° multi-section impedance matching transmission microstrip lines.

[0044] Further, the alumina ceramic piece 3 is a ceramic material with a dielectric constant of 2-10.

[0045] Further, the permanent magnet 4 is a samarium-cobalt permanent magnet.

[0046] Further, the upper surface of the alloy base plate 1 and the lower surface of the substrate 2 are fixed together by welding.

[0047] Further, the square ceramic piece (ceramic piece 5) and the ferrite round piece (ferrite piece 6) in the substrate 2 are combined together by gluing or co-firing.

[0048] Further, the microstrip circuit 7 is prepared on the surface of the substrate 2 by a process of electroplating, sputtering, photolithography, and etching.

[0049] Further, the lower surface of the alumina ceramic piece 3 is combined with the microstrip circuit 7 above the substrate 2 by gluing.

[0050] Further, the lower surface of the permanent magnet 4 is fixed with the upper surface of the alumina ceramic piece 3 by gluing.

[0051] The high-power microstrip circulator (microstrip circulator) of the application improves the power bearing capacity of the circulator (microstrip circulator) by using ion-doped ferrite material and designing a suitable microstrip circuit pattern, has advantages of high power, wide band, low loss, etc., can meet the performance requirements of users for excellent electrical performance indicators and high power resistance, and is suitable for high-performance microwave integrated circuits.

[0052] As shown in Figures 1 to 3 Further, the microstrip circuit 7 is a disc junction circuit, the middle part of the microstrip circuit 7 covers the ferrite piece 6, and the microstrip circuit 7 is connected with a plurality of transmission microstrip lines; the width of the transmission microstrip line is not less than a preset value.

[0053] The beneficial effects of the above further technical solutions are: the disc junction circuit is adopted, the area of the center junction circuit completely covers the ferrite round piece in the middle of the substrate, the width of the line of the microstrip circuit is controlled as wide as possible on the basis of ensuring performance indicators, and the power bearing capacity of the circulator is further improved.

[0054] As shown in Figures 1 to 3As shown, further, the plurality of transmission microstrip lines are three intersecting 120° multi-section impedance matching transmission microstrip lines, the plurality of transmission microstrip lines are all located on the ceramic sheet 5, and the transmission microstrip lines outside the port matching transmission lines located on the ceramic sheet 5 are each connected with a port matching transmission line, the width of the transmission microstrip line outside the port matching transmission line located on the ceramic sheet 5 is not less than a preset value, and the preset value is 0.45 mm.

[0055] The beneficial effect of the above further technical solution is that the disc junction circuit is adopted to completely cover the ferrite disc in the middle of the substrate by the area of the center junction circuit, the line width of the microstrip circuit is controlled to be as wide as possible on the basis of ensuring the performance index, and the power bearing capacity of the circulator is further improved. By adopting the ion-doped ferrite material and designing a suitable microstrip circuit pattern, the power bearing capacity of the circulator is improved, and the circulator has the advantages of high power, wide band, and low loss, can meet the performance requirements of excellent electrical performance index and high power resistance of users, and is suitable for high-performance microwave integrated circuits.

[0056] As shown in Figures 1 to 3 Further, the ceramic sheet 5 is a square ceramic sheet, the ferrite disc 6 is a ferrite disc, and the ferrite disc 6 is embedded in the middle of the ceramic sheet 5; and the alumina ceramic sheet 3 is a circular structure.

[0057] The beneficial effect of the above further technical solution is that the ion-doped ferrite disc and the square ceramic sheet are combined together as the substrate of the microstrip circulator, the power bearing capacity of the ferrite material is regulated and controlled by ion doping, and at the same time, the ceramic material with high power bearing capacity is used as part of the substrate, so that the power bearing capacity of the microstrip circulator is essentially improved.

[0058] Further, the ceramic sheet 5 is made of ceramic material with a dielectric constant of 10-50; the ferrite disc 6 is made of cobalt ion-doped garnet and spinel ferrite material; the alumina ceramic sheet 3 is made of ceramic material with a dielectric constant of 2-10; and the alloy bottom plate 1 is made of magnetic metal, and the permanent magnet 4 is a samarium-cobalt permanent magnet.

[0059] The beneficial effect of the above further technical solution is that the power bearing capacity of the ferrite material is regulated and controlled by ion doping, and at the same time, the ceramic material with high power bearing capacity is used as part of the substrate, so that the power bearing capacity of the microstrip circulator is essentially improved.

[0060] As shown in Figures 1 to 3 Further, the microstrip circuit 7 is a microstrip circuit prepared on the surface of the substrate 2 by a process mode of electroplating, sputtering, photolithography, and etching.

[0061] The beneficial effects of the further technical solutions are that the metal layer of the microstrip circuit bottom layer is prepared by electroplating, the surface gold layer is prepared by magnetron sputtering, the microstrip circuit pattern plate is made by a photoetching machine, and the high-precision microstrip circuit pattern is prepared on the surface of the substrate by chemical etching.

[0062] As shown in Figures 1 to 3 Further, the alloy bottom plate 1 is welded with the lower surface of the substrate 2, the ferrite sheet 6 is embedded on the ceramic sheet 5 by gluing or co-firing, the lower surface of the alumina ceramic sheet 3 is fixedly connected with the microstrip circuit 7 on the substrate 2 by gluing, and the lower surface of the permanent magnet 4 is fixedly connected with the upper surface of the alumina ceramic sheet 3 by gluing.

[0063] The beneficial effects of the further technical solutions are that the permanent magnet is a samarium-cobalt permanent magnet, and the permanent magnet and the alumina ceramic sheet are bonded together by epoxy glue to provide a uniform magnetic field.

[0064] Further, the lower surface of the permanent magnet 4 is fixedly connected with the upper surface of the alumina ceramic sheet 3 by epoxy gluing.

[0065] The beneficial effects of the further technical solutions are that the permanent magnet is a samarium-cobalt permanent magnet, and the permanent magnet and the alumina ceramic sheet are bonded together by epoxy glue to provide a uniform magnetic field.

[0066] Further, the dielectric constant of the ceramic sheet 5 is 21, the dielectric constant of the ferrite sheet 6 is 14, the saturation magnetization of the ferrite sheet 6 is 3200Gs, and the dielectric constant of the alumina ceramic sheet 3 is 8.6.

[0067] The beneficial effects of the further technical solutions are that the dielectric constant and the saturation magnetization of each component are controlled to ensure performance indicators.

[0068] Further, the surface of the alloy bottom plate 1 is plated with silver, the thickness of the alloy bottom plate 1 is 0.3mm, the thickness of the substrate 2 is 0.5mm, and the diameter of the ferrite sheet 6 is 3mm.

[0069] The beneficial effects of the further technical solutions are that the size of each component is controlled to ensure high integration and miniaturization.

[0070] This invention provides a microstrip circulator. An alloy base plate 1 is made of magnetic metal, and its upper surface and the lower surface of a substrate 2 are fixed together by welding. The substrate 2 contains a square ceramic sheet (ceramic sheet 5) with a dielectric constant of 10-50, and a ferrite disc (ferrite sheet 6) made of ion-doped garnet or spinel ferrite material, which are bonded together by adhesive bonding or co-firing. The microstrip circuit 7 is a disk junction circuit, consisting of a central disk completely covering the ferrite disc (ferrite sheet 6) and three intersecting multi-section impedance-matching transmission microstrip lines at 120° intervals, fabricated on the surface of the substrate 2 through electroplating, sputtering, photolithography, and etching processes. An alumina ceramic sheet 3 is made of a ceramic material with a dielectric constant of 2-10, and its lower surface is bonded to the microstrip circuit 7 above the substrate 2 by adhesive bonding. A permanent magnet 4 is a samarium-cobalt permanent magnet, and its lower surface is fixed to the upper surface of the alumina ceramic sheet 3 by adhesive bonding.

[0071] In one specific embodiment, the alloy base plate 1 is made of permalloy, silver-plated, and 0.3 mm thick, and is fixed to the substrate 2 by soldering.

[0072] In one specific embodiment, the square ceramic sheet (ceramic sheet 5) of substrate 2 and the central ferrite disc (ferrite sheet 6) are bonded together by adhesive, with a thickness of 0.5 mm. Figure 2 As shown; the square ceramic sheet (ceramic sheet 5) has a dielectric constant of 21, and the ferrite disc (ferrite sheet 6) is made of Co. 2+ A spinel ferrite doped with cobalt ions has a diameter of 3 mm, a dielectric constant of 14, and a saturation magnetization of 3200 Gs.

[0073] In one specific embodiment, the microstrip circuit 7 is designed as a disk junction circuit, with the central disk completely covering the central ferrite disc (ferrite disc 6) and connected to three multi-section impedance matching transmission microstrip lines intersecting at 120°. Except for the port matching transmission line located on the square ceramic disc (ceramic disc 5), the width of the remaining transmission microstrip lines is ≥0.45mm. Figure 3 As shown, the metal layer of the bottom layer of the microstrip circuit 7 is prepared by electroplating, the surface gold layer is prepared by magnetron sputtering, the microstrip circuit pattern board is fabricated using a photolithography machine, and a high-precision microstrip circuit pattern is prepared on the surface of the substrate 2 by chemical etching.

[0074] In one specific embodiment, the alumina ceramic sheet 3 is circular with a dielectric constant of 8.6 and is bonded to the upper surface of the substrate 2 with epoxy adhesive.

[0075] In one specific embodiment, the permanent magnet 4 is a samarium cobalt permanent magnet, which is bonded to the alumina ceramic sheet 3 with epoxy adhesive to provide a uniform magnetic field.

[0076] The high-power microstrip circulator (microstrip circulator) of one embodiment of the application works in the X-band full band, in the frequency range of 8-12GHz, realizes the performance index of peak power capacity ≥250W, insertion loss ≤0.5dB, isolation ≥20dB, and voltage standing wave ratio ≤1.25.

[0077] (1) Compared with the undoped full ferrite substrate of the traditional microstrip circulator, the high-power microstrip circulator (microstrip circulator) of the application adopts ion-doped ferrite disc and square ceramic piece combined together as the substrate of the microstrip circulator, adjusts and controls the power bearing capacity of the ferrite material through ion doping, and at the same time adopts the ceramic material with high power bearing capacity as part of the substrate, which essentially improves the power bearing capacity of the microstrip circulator.

[0078] (2) The microstrip circuit design of the high-power microstrip circulator (microstrip circulator) of the application adopts disc junction circuit, so that the area of the center junction circuit completely covers the ferrite disc in the middle of the substrate, controls the line width of the microstrip circuit as wide as possible on the basis of ensuring the performance index, and further improves the power bearing capacity of the circulator.

[0079] Finally, it should be pointed out that: the above embodiments are only used to illustrate the technical solutions of the application, but not to limit them; although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the application.

Claims

1. A microstrip circulator, characterized in that, include: The alloy base plate (1), substrate (2), alumina ceramic sheet (3), permanent magnet (4) and microstrip circuit (7) are provided in the substrate (2), the ceramic sheet (5) and the ion-doped ferrite sheet (6) are provided in the substrate (2), the ferrite sheet (6) is embedded on the ceramic sheet (5), the substrate (2) is mounted on the alloy base plate (1), the alumina ceramic sheet (3) and the microstrip circuit (7) are both mounted on the substrate (2), and the permanent magnet (4) is mounted on the alumina ceramic sheet (3).

2. A microstrip circulator according to claim 1, characterized in that, The microstrip circuit (7) is a disk junction circuit. The ferrite sheet (6) is covered in the middle of the microstrip circuit (7). The microstrip circuit (7) is connected to multiple transmission microstrip lines. The width of the transmission microstrip lines is not less than a preset value.

3. A microstrip circulator according to claim 2, characterized in that, The multiple transmission microstrip lines are three multi-section impedance matching transmission microstrip lines intersecting at 120°. The multiple transmission microstrip lines are all located on the ceramic plate (5). Port matching transmission lines are connected to the multiple transmission microstrip lines respectively. The width of the transmission microstrip lines other than the port matching transmission lines on the ceramic plate (5) is not less than a preset value, which is 0.45mm.

4. A microstrip circulator according to claim 1, characterized in that, The ceramic sheet (5) is a square ceramic sheet, the ferrite sheet (6) is a ferrite disc, and the ferrite sheet (6) is embedded in the middle of the ceramic sheet (5); the alumina ceramic sheet (3) has a circular structure.

5. A microstrip circulator according to claim 1, characterized in that, The ceramic sheet (5) is made of ceramic material with a dielectric constant of 10-50; the ferrite sheet (6) is made of cobalt ion-doped garnet and spinel ferrite material; the alumina ceramic sheet (3) is made of ceramic material with a dielectric constant of 2-10; the alloy base plate (1) is made of magnetic metal; and the permanent magnet (4) is a samarium cobalt permanent magnet.

6. A microstrip circulator according to claim 1, characterized in that, The microstrip circuit (7) is a microstrip circuit fabricated on the surface of the substrate (2) by electroplating, sputtering, photolithography and etching processes.

7. A microstrip circulator according to claim 1, characterized in that, The alloy base plate (1) is welded to the lower surface of the substrate (2), the ferrite sheet (6) is embedded on the ceramic sheet (5) by adhesive bonding or co-firing, the lower surface of the alumina ceramic sheet (3) is fixedly connected to the microstrip circuit (7) above the substrate (2) by adhesive bonding, and the lower surface of the permanent magnet (4) is fixedly connected to the upper surface of the alumina ceramic sheet (3) by adhesive bonding.

8. A microstrip circulator according to claim 7, characterized in that, The lower surface of the permanent magnet (4) is fixedly connected to the upper surface of the alumina ceramic sheet (3) by means of epoxy adhesive.

9. A microstrip circulator according to claim 1, characterized in that, The dielectric constant of the ceramic sheet (5) is 21, the dielectric constant of the ferrite sheet (6) is 14, the saturation magnetization of the ferrite sheet (6) is 3200 Gs, and the dielectric constant of the alumina ceramic sheet (3) is 8.

6.

10. A microstrip circulator according to claim 1, characterized in that, The alloy base plate (1) is silver plated on its surface. The alloy base plate (1) has a thickness of 0.3 mm. The substrate (2) has a thickness of 0.5 mm. The ferrite sheet (6) has a diameter of 3 mm.

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