L / S wave band ferrite circulator resistant to high peak power

Abstract

The invention discloses an L / S wave band ferrite circulator resistant to high peak power, and belongs to the technical field of microwave devices, the L / S wave band ferrite circulator resistant to high peak power comprises an upper substrate (4), an upper medium (5), a central conductor (6), a lower medium (7) and a lower substrate (8), the upper medium (5) and the lower medium (7) serve as labyrinth media, a gap (10) is arranged between the labyrinth media and the central conductor (6), and the width of the gap (10) is smaller than or equal to 1 mm; the thickness of the central conductor is 0.5 mm to 1 mm. The thickness of the upper substrate (4) and the thickness of the lower substrate (8) are 1.5 mm to 3 mm. The nesting surface of the upper substrate (4) and the upper medium (5) is inclined, the nesting surface of the lower medium (7) and the lower substrate (8) is inclined, and the inclination angle is 65-75 degrees; according to the invention, the high peak power resistance of the L / S wave band ferrite circulator can be improved to a myriawatt level; silicone rubber filling amount can be reduced, and filling quality can be improved; the method can be widely applied to satellite-borne, airborne, ground, ship-borne and other microwave systems.

Description

Technical Field

[0001] The invention relates to the technical field of microwave devices, and in particular to an L / S band ferrite circulator capable of withstanding high peak power. Background Art

[0002] With the development of science and technology, new requirements have been put forward for the power level of microwave systems in technical fields such as early warning perception and ground detection. For example, the peak power level of microwave systems for high-orbit satellites and new-generation early warning aircraft has been increased to 10,000 watts or even tens of 10,000 watts. Taking high-orbit satellites as an example, high-orbit satellites are widely used in various scientific fields such as ground detection, communication, and meteorology due to their unique high-orbit and geostationary characteristics, and have become important orbital resources. Miniaturized L / S-band high-power microwave ferrite circulators are the core components of high-orbit satellite payloads. Usually, their peak power resistance requirements are up to 10,000 watts, which puts forward new requirements for the high peak power resistance design of L / S-band high-power microwave ferrite circulators.

[0003] The usual method to improve the high peak power resistance of L / S band ferrite circulators is to fill the product with silicone rubber to prevent air breakdown, so as to obtain the circulator's ability to withstand high peak power, while improving the circulator's reliability and service life, and effectively ensuring the long-term stable and reliable operation of the microwave system.

[0004] Conventional high peak power microwave ferrite circulators generally achieve high peak power resistance by changing the breakdown resistance of the filling medium, such as filling silicone rubber around the circuit. The breakdown field strength of silicone rubber is about two orders of magnitude greater than that of air, which is effective for L / S band ferrite circulators that can withstand several kilowatts of peak power. However, the ultra-high peak power L / S band ferrite circulators used in high-orbit satellites and new generation early warning aircraft need to withstand peak powers of more than 10,000 watts. Due to the higher quality requirements for silicone rubber filling, it is difficult to meet the requirements simply by using traditional dielectric filling methods. Specifically, on the one hand, high peak power brings high electric field strength, and the silicone rubber that needs to be filled is thicker. The uneven curing speed of thicker silicone rubber makes it difficult to completely remove the internal air, forming voids or bubbles, which makes it difficult for the ferrite circulator to withstand high peak powers of 10,000 watts. On the other hand, conventional L / S band ferrite circulators usually use a central conductor of about 0.2mm. In this frequency band, the thickness of the substrate is often between 0.7mm and 1.2mm. The closest distance between the central conductor and the ground is often the distance from the substrate to the ground. When passing ultra-high peak power, the electric field strength is high, which can easily cause breakdown and sparking.

[0005] The typical structure of a circulator is as follows: Figure 1As shown, from top to bottom, it includes a gasket 1, a permanent magnet 2, an upper cavity 3, an upper substrate 4, an upper dielectric 5, a central conductor 6, a lower dielectric 7, a lower substrate 8 and a lower cavity 9, wherein the upper dielectric 5 and the lower dielectric 7 are used as labyrinth media; wherein, in order to increase the peak power, during assembly, as Figure 2 As shown, silicone rubber is filled in the gap 10 between the labyrinth medium and the central conductor 6. The conventional gap 10 is relatively large (≥3 mm), and the amount of silicone rubber filled is relatively large.

[0006] In addition, during assembly, the upper substrate 4 is nested in the upper dielectric 5, and the lower substrate 8 is nested in the lower dielectric 7, and the nesting surfaces of the substrate and the dielectric are vertical surfaces, so that such assembly can easily make the center conductor directly grounded. In addition, the existing circuits including the center conductor 6 often have sharp angles such as acute angles, right angles, and obtuse angles, which leads to energy concentration at the corners and a large electric field strength.

[0007] That is, the existing method of achieving high peak power resistance by changing the breakdown resistance of the filling medium (filled silicone rubber) is effective for L / S band ferrite circulators that can withstand peak powers of several kilowatts. However, for L / S band ferrite circulators that can withstand peak powers of more than 10,000 watts, higher quality requirements are placed on the filling silicone rubber, and current conventional designs are difficult to meet the requirements. Summary of the invention

[0008] The purpose of the present invention is to provide a L / S band ferrite circulator capable of withstanding high peak power to solve the above problems.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is as follows: An L / S band ferrite circulator resistant to high peak power, comprising an upper substrate, an upper dielectric, a central conductor, a lower dielectric and a lower substrate, wherein the upper dielectric is nested in the upper substrate, the lower substrate is nested in the lower dielectric, the upper dielectric and the lower dielectric serve as a labyrinth medium, a gap is provided between the labyrinth medium and the central conductor, and the width of the gap is ≤1 mm; The present invention can reduce the amount of silicone rubber filling by reducing the gap between the labyrinth medium and the central conductor, which is beneficial to shortening the curing time of silicone rubber. At the same time, since the improved silicone rubber filling volume is small, it can avoid the formation of large bubbles or voids, which is beneficial to improving the filling quality and thus improving the ability to withstand peak power. If the filling quality is not good, large bubbles will appear in the high electric field area of ​​the circuit, and the high electric field strength will break through the bubbles, causing the product to ignite and discharge and fail; the present invention improves the filling quality and the ability to withstand peak power while shortening the curing time of silicone rubber.

[0010] The thickness of the central conductor is 0.5mm-1mm, preferably 1mm; the thickness of the upper substrate and the lower substrate are both 1.5mm-3mm, preferably 3mm. The thickness of the traditional central conductor is generally 0.2mm, and the thickness of the traditional substrate is about 0.7-1.2mm; by increasing the thickness of the central conductor and the substrate, and increasing the distance between the central conductor and the ground, the electric field strength can be effectively reduced.

[0011] According to the formula: , where f is the operating frequency and d is the metal gap. From the formula, it can be seen that the higher the frequency and the larger the metal gap, the greater the power capacity. The present invention further increases the thickness of the central conductor and the substrate and increases the distance between the central conductor and the ground, thereby effectively reducing the electric field strength.

[0012] As a preferred technical solution: the nesting surfaces of the upper substrate and the upper medium are inclined, and the nesting surfaces of the lower medium and the lower substrate are inclined, and the inclination angle is 65° to 75°.

[0013] The present invention further makes the nesting surface tilted, thereby preventing the central conductor from directly contacting the ground and cutting off the discharge path of the central conductor to the ground. The bevel angle here is designed to prevent the central conductor from directly contacting the ground. Its size has no corresponding relationship with the magnitude of the increased peak power. Its size actually depends on the ease of processing of the substrate. The smaller the bevel angle, the thinner the edge of the substrate is and the easier it is to collapse. The closer to verticality, the dielectric shrinks in a low temperature environment, and it is still possible for the central conductor to be exposed and directly contact the ground. In short, it is the optimal value considering the thermal expansion and contraction of the material and the difficulty of processing.

[0014] As a preferred technical solution: rounding all sharp corners of the circuit. Rounding the circuit including the central conductor corners (acute angles, right angles, obtuse angles) can avoid the energy concentration of the central conductor at the corners, effectively reduce the electric field strength at the corners, and help improve the power capacity.

[0015] Considering the worst case, the air breakdown field strength is 3×10 6 v / m. From the electric field simulation results, it can be seen that when the peak power of 80000W is passed, the electric field strength of the present invention is 2.98×10 6 v / m, so in the worst case, the present invention can theoretically withstand a peak power of 80000W. In fact, the present invention mentions that the gap between the center conductor and the medium will be fully filled with silicone rubber, so theoretically there is no direct contact between the air and the center conductor, and the breakdown field strength of the air filled with silicone rubber is usually 10 8 v / m level, with sufficient margin. Therefore, considering the worst case, the present invention can theoretically withstand at least 80000W peak power.

[0016] Compared with the prior art, the advantages of the present invention are: the present invention can improve the high peak power resistance capability of the L / S band ferrite circulator to the 10,000 watt level; reducing the gap between the labyrinth medium and the central conductor can reduce the silicone rubber filling amount, which is beneficial to shorten the curing time of the silicone rubber and improve production efficiency. At the same time, the silicone rubber filling volume is small and it is difficult to form large bubbles or voids, which is beneficial to improving the filling quality; after breaking through the technical bottleneck, the product can be widely used in satellite-borne, airborne, ground-based, ship-borne and other microwave systems, and has great military and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a typical circulator breakdown structure diagram; Figure 2 It is an assembly diagram of a central conductor and a labyrinth medium in the prior art; Figure 3 It is an assembly diagram of the central conductor and the labyrinth medium of Example 1 of the present invention; Figure 4 This is a schematic diagram of the assembly of the central conductor and substrate of Example 1 of the present invention; Figure 5 A cross-sectional view of the nesting of the upper substrate and the upper medium of Embodiment 1 of the present invention; Figure 6 This is a diagram of the central conductor structure of Embodiment 1 of the present invention; Figure 7 This is a simulation result diagram of the circulator of Example 1 of the present invention at an electric field strength of 10000W; Figure 8 This is a simulation result diagram of the circulator of Example 1 of the present invention at an electric field strength of 20000W; Fig. 9 This is a simulation result diagram of the circulator of Example 1 of the present invention at an electric field strength of 30000W; Fig.10 This is a simulation result diagram of the circulator of Example 1 of the present invention at an electric field strength of 40000W; Fig.11 This is a simulation result diagram of the circulator of Example 1 of the present invention at an electric field strength of 50000W; Fig.12 This is a simulation result diagram of the circulator of Example 1 of the present invention at an electric field strength of 60000W; Fig.13 This is a simulation result diagram of the circulator of Example 1 of the present invention at an electric field strength of 70000W; Fig.14 This is a simulation result diagram of the circulator of Example 1 of the present invention at an electric field strength of 80000W; In the figure: 1, gasket; 2, permanent magnet; 3, upper cavity; 4, upper substrate; 5, upper dielectric; 6, center conductor; 7, lower dielectric; 8, lower substrate; 9, lower cavity; 10, gap. DETAILED DESCRIPTION

[0018] The present invention will be further described below in conjunction with the accompanying drawings.

[0019] Embodiment 1:

[0020] A L / S band ferrite circulator with high peak power resistance, comprising an upper substrate 4, an upper dielectric 5, a central conductor 6, a lower dielectric 7 and a lower substrate 8, wherein the upper dielectric 5 is nested in the upper substrate 4, the lower substrate 8 is nested in the lower dielectric 7, the upper dielectric 5 and the lower dielectric 7 are used as labyrinth media, and a gap 10 is provided between the labyrinth media and the central conductor 6. In this embodiment, Figure 3 As shown, the width of the gap 10 is 0.9 mm; In this embodiment, the thickness of the central conductor 6 is 1 mm, and the thickness of the upper substrate 4 and the lower substrate 8 are both 3 mm. Figure 4 As shown; In this embodiment, the nesting surfaces of the upper substrate 4 and the upper medium 5 are inclined, and the nesting surfaces of the lower medium 7 and the lower substrate 8 are inclined, and the inclination angle is 75°. Figure 5 As shown; In this embodiment, the corners of the central conductor 6 are rounded, and the radius of the rounded corners is 1 / 3 of the corresponding side length. Figure 6 As shown; The electric field simulations of the circulator of this embodiment were performed at different powers. The results are as follows: Figures 7 to 14 As shown in the figure, it can be seen that considering the worst case, the air breakdown field strength is 3×10 6 v / m. From the electric field simulation results, it can be seen that when the peak power of 80000W is passed, the electric field strength of the present invention is 2.98×10 6 v / m, so in the worst case, the present invention can theoretically withstand a peak power of 80000W. In fact, the present invention mentions that the gap between the center conductor and the medium will be fully filled with silicone rubber, so theoretically there is no direct contact between the air and the center conductor, and the breakdown field strength of the air filled with silicone rubber is usually 10 8 v / m level, with sufficient margin. Therefore, considering the worst case, the present invention can theoretically withstand at least 80000W peak power.

[0021] Embodiment 2:

[0022] In this embodiment, the width of the gap 10 is 0.6mm, the thickness of the central conductor 6 is 0.5mm, the thickness of the upper substrate 4 and the lower substrate 8 are both 1.5m, the nesting surfaces of the upper substrate 4 and the upper dielectric 5 are inclined, and the nesting surfaces of the lower dielectric 7 and the lower substrate 8 are inclined, and the inclination angle is 65°. The rest is the same as in Example 1; the peak power resistance of the circulator in this embodiment is 80000W.

[0023] Embodiment 3:

[0024] In this embodiment, the width of the gap 10 is 0.8 mm, the thickness of the central conductor 6 is 0.8 mm, the thickness of the upper substrate 4 and the lower substrate 8 are both 2.5 m, the nesting surfaces of the upper substrate 4 and the upper dielectric 5 are inclined, and the nesting surfaces of the lower dielectric 7 and the lower substrate 8 are inclined, and the inclination angle is 70°. The rest is the same as in Example 1; the peak power resistance of the circulator in this embodiment is 80,000 W.

[0025] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An L / S band ferrite circulator capable of withstanding high peak power, comprising an upper substrate (4), an upper dielectric (5), a central conductor (6), a lower dielectric (7) and a lower substrate (8), wherein: The upper medium (5) is nested in the upper substrate (4), and the lower substrate (8) is nested in the lower medium (7). The upper medium (5) and the lower medium (7) serve as a labyrinth medium. A gap (10) is provided between the labyrinth medium and the central conductor (6), characterized in that: the width of the gap (10) is ≤1 mm; The thickness of the central conductor is 0.5 mm to 1 mm, and the thickness of the upper substrate (4) and the lower substrate (8) are both 1.5 mm to 3 mm.

2. The L / S band ferrite circulator with high peak power resistance according to claim 1, characterized in that: The nesting surfaces of the upper substrate (4) and the upper medium (5) are inclined, and the nesting surfaces of the lower medium (7) and the lower substrate (8) are inclined, with the inclination angle being 65° to 75°.

3. The L / S band ferrite circulator with high peak power resistance according to claim 1, characterized in that: The center conductor (6) has rounded corners.

4. The L / S band ferrite circulator capable of withstanding high peak power according to claim 3, characterized in that: The fillet radius is 1 / 5 to 1 / 2 of the corresponding side length.

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