High-reliability output antenna structure of high-power pulse space traveling wave tube

Abstract

The invention relates to the technical field of pulse space traveling-wave tubes, and discloses a high-reliability output antenna structure of a high-power pulse space traveling-wave tube, which comprises an antenna spiral line which comprises a spiral line main body and an output antenna which are integrally formed; an inner conductor is arranged in the tube shell, the output antenna is inserted into a groove in the top of the inner conductor, and the spiral line body is located in the center of the tube shell. A plurality of clamping rods are arranged in the antenna spiral line; and the plurality of clamping rods are tightly clamped with the integrated antenna spiral line in a thermal expansion mode. A section of tungsten strip extends from the last circle of screw pitch of an output spiral line to serve as an output antenna, the output antenna is used for replacing an original platinum strip structure output antenna, the reliability of the high-power pulse space traveling wave tube is effectively improved through the structure, and the extended tungsten strip is inserted into a groove in the top of a conductor in an output energy transmission system. And the tungsten strip and the inner conductor are firmly welded by laser welding, so that the reliability of the output antenna is effectively improved by the structure.

Description

Technical Field

[0001] The present invention relates to the technical field of pulsed space traveling wave tubes, and specifically to a high-reliability output antenna structure for high-power pulsed space traveling wave tubes. Background Art

[0002] Due to its advantages such as wide operating bandwidth, high frequency stability, and low control voltage, pulsed space traveling wave tubes are widely used in military and civilian satellite systems such as rapidly deployed SAR satellites, microwave remote sensing satellites, microwave mapping satellites, and ocean satellites. High-power pulsed space traveling wave tubes are key single units in spaceborne radar systems, realizing microwave amplification functions. Open circuit of the output antenna is a single-point failure of high-power space traveling wave tubes and is a key risk concerned during the development and production of traveling wave tubes.

[0003] In the existing high-power pulsed space traveling wave tube technology, platinum strips are usually used as conductors for the output antenna. As a material, platinum has good electrical conductivity and high-temperature resistance in a conventional environment, but its melting point is relatively low, about 1772°C. During high-power pulsed operation, especially when a high-power pulse is input, the temperature of the output antenna will rise rapidly, resulting in a risk that the platinum strip may be melted. Due to the relatively low melting point of platinum, when the temperature exceeds its limit, it may cause the output antenna to fail, affecting the stability and reliability of the entire traveling wave tube system.

[0004] In addition, the existing platinum strip output antenna structure is prone to fatigue and damage in a high-power pulse environment. Especially when the traveling wave tube operates in a high-temperature environment, the fatigue resistance of platinum material is limited. Long-term temperature fluctuations and repeated pulse excitations may cause the performance of the platinum strip to decline, and even lead to fracture or unstable connection. This will increase the failure rate of the traveling wave tube system. Especially in extreme tests under high and low temperature environments, the traveling wave tube often shows insufficient stability, affecting the long-term reliability of the product.

[0005] Therefore, the application of the existing platinum strip structure in high-power pulsed space traveling wave tubes cannot fully meet the requirements for reliability and stability in a high-power pulse working environment. Its fusible and fatigue-prone characteristics limit the long-term stable operation of the traveling wave tube in a harsh environment and become key problems that need to be improved and solved in traveling wave tube technology. Summary of the Invention

[0006] Aiming at the deficiencies of the existing technology, the present invention provides a high-reliability output antenna structure for high-power pulsed space traveling wave tubes, solving the problems of easy melting and insufficient fatigue resistance of platinum strips during high-power pulsed operation in the existing technology.

[0007] To achieve the above objectives, the present invention is realized through the following technical solutions: A high-reliability output antenna structure for high-power pulsed space traveling wave tubes, comprising:

[0008] An antenna helix, which includes a helix body and an output antenna, and the helix body and the output antenna are integrally formed;

[0009] A tube shell, inside which an inner conductor is arranged, the output antenna is inserted into a groove at the top of the inner conductor, and the helix body is located at the center of the tube shell.

[0010] Preferably, a plurality of clamping rods are arranged inside the antenna helix, and the plurality of clamping rods are tightly clamped with the integrated antenna helix by means of thermal expansion.

[0011] Preferably, the clamping rod is in a triangular pyramid structure, a conical structure or a cylindrical structure.

[0012] Preferably, the output antenna is a section of tungsten strip extending from the end of the helix body.

[0013] Preferably, at the connection between the output antenna and the groove at the top of the output energy transmission inner conductor, laser welding technology is used for welding and fixing.

[0014] Preferably, the tube shell is of a circular design, and the plurality of clamping rods are symmetric with each other and are equidistantly distributed outside the helix body.

[0015] The present invention provides a high-reliability output antenna structure for a high-power pulsed space traveling wave tube. It has the following beneficial effects:

[0016] In the present invention, a section of tungsten strip is extended from the pitch of the last turn of the output helix as the output antenna, replacing the original platinum strip structure output antenna. This structure effectively improves the reliability of the high-power pulsed space traveling wave tube. The extended tungsten strip is inserted into the groove at the top of the output energy transmission system inner conductor, and laser welding is used to firmly weld the tungsten strip to the inner conductor. This structure effectively improves the reliability of the output antenna and reduces the risk of open circuit of the output antenna. Description of the Drawings

[0017] Figure 1 It is a schematic structural diagram of the output antenna structure of the present invention;

[0018] Figure 2 It is a schematic structural diagram of the output antenna of the present invention.

[0019] Among them, 1. Antenna helix; 1-1. Helix body; 1-2. Output antenna; 2. Inner conductor; 3. Clamping rod; 4. Tube shell. Detailed Embodiments

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0021] Please refer to the attached Figure 1 - attached Figure 2 , the embodiments of the present invention provide a high-reliability output antenna structure for a high-power pulsed space traveling wave tube, including:

[0022] Antenna helix 1, which includes a helix body 1-1 and an output antenna 1-2, and the helix body 1-1 and the output antenna 1-2 are integrally formed;

[0023] Tube shell 4, inside which an inner conductor 2 is provided, the output antenna 1-2 is inserted into the top groove of the inner conductor 2, and the helix body 1-1 is located at the central position of the tube shell 4.

[0024] The output antenna 1-2 is a section of tungsten strip extending from the end of the helix body 1-1.

[0025] The connection between the output antenna 1-2 and the top groove of the output energy transmission inner conductor 2 is fixed by laser welding technology.

[0026] Specifically, the antenna helix 1 is integrally formed by the helix body 1-1 and the output antenna 1-2, forming a complete antenna assembly. During operation, the helix body 1-1 conducts the electromagnetic wave signal to the output antenna part through the helical shape.

[0027] The output antenna 1-2 is located at the end of the helix body 1-1, formed by physical extension, and is connected to the inner conductor 2 inside the tube shell 4. Specifically, the output antenna 1-2 is inserted into the groove at the top of the inner conductor 2, and this design ensures the smooth flow of the signal from the output antenna 1-2 to the inner conductor 2, avoiding any resistance in the signal transmission.

[0028] During the working process, the microwave signal generated by the helix body 1 propagates along the helix and smoothly enters the inner conductor 2 after passing through the output antenna 1-2, finally realizing the signal output. Through this design, the structure not only ensures the efficient operation of the antenna but also improves the overall stability of the system. Compared with the prior art, the traditional output antenna 1-2 is bent into shapes such as L-shaped or S-shaped using platinum strips or platinum wires. The output antenna 1-2 is an S-shaped platinum antenna, with one end spot-welded to the inner conductor 2 and the other end welded to the helix by laser welding. Due to the high output power and large duty cycle of high-power pulsed traveling wave tubes, the problem of the output antenna 1-2 being prone to fusing faults is likely to occur. In the present invention, through the integrated structure design of the helix body 1-1 and the output antenna 1-2, the tungsten strip extended from the end of the output helix is used as the output antenna 1-2, and the output antenna 1-2 is inserted into the top groove of the output energy transmission inner conductor 2 and welded by laser welding. By optimizing the structure of the output antenna 1-2, the present invention designs the output antenna 1-2 and the helix body 1-1 as one part, removing the welding between the output antenna 1-2 and the helix body 1-1. The melting point of the output antenna 1-2 is increased from 1772 °C (melting point of platinum) to 3410 °C (melting point of tungsten), reducing the risk of the output antenna 1-2 fusing, improving the reliability of high-power pulsed traveling wave tubes, solving the problem that the traveling wave tube suddenly has no output power during the high and low temperature test process, and ensuring the progress of product development.

[0029] A plurality of clamping rods 3 are arranged inside the antenna helix 1, and the plurality of clamping rods 3 are tightly clamped with the integrated antenna helix 1 by means of thermal expansion.

[0030] The clamping rod 3 is in a triangular pyramid structure, a conical structure or a cylindrical structure.

[0031] Specifically, when the antenna is working under high-power pulses, the structure inside will undergo thermal expansion due to temperature changes. The design of the clamping rod 3 utilizes this characteristic, enabling it to form a tight clamping force with the antenna helix 1 through thermal expansion. The thermal expansion characteristic of the clamping rod 3 causes it to automatically expand when the temperature rises, enhancing the contact force with the antenna helix 1, thereby maintaining the physical stability of the antenna during the working process and preventing loosening or displacement in a high-temperature environment.

[0032] The clamping rod 3 can adopt different structural forms, such as a triangular pyramid structure, a conical structure or a cylindrical structure. These designs all ensure the stable connection between the clamping rod 3 and the antenna helix 1. The triangular pyramid structure provides better symmetry and stability, the conical structure helps to provide a gradually increasing contact force, and the cylindrical structure can evenly distribute the clamping force, avoiding damage caused by excessive local stress.

[0033] The tube shell 4 is designed in a circular shape, and the plurality of clamping rods 3 are symmetric with each other and evenly distributed outside the antenna helix 1.

[0034] Specifically, in the antenna structure, the tube shell 4 adopts a circular design, which provides stable support and protection. A plurality of clamping rods 3 are distributed outside the antenna helix 1 in a symmetrical and equidistant manner. This design ensures that the clamping rods 3 are evenly stressed, thereby avoiding excessive stress on any side and preventing the antenna helix 1 from being deformed or offset.

[0035] The clamping rod 3 ensures the stability of the antenna structure by contacting the antenna helix 1. When the temperature changes or the heat generated during operation affects the antenna structure, the symmetrical layout of the clamping rod 3 can effectively disperse the stress caused by thermal expansion, further stabilizing the position and shape of the antenna helix 1. In this way, the design of the tube shell 4 and the clamping rod 3 work together to ensure that the antenna can still maintain a good working condition in a high temperature environment.

[0036] Working principle: First, the helical wire body 1-1 and the output antenna 1-2 are integrally formed, making the entire antenna structure more stable during operation, which solves the existing technology. The traditional output antenna 1-2 uses a platinum strip or platinum wire bent into an L-shaped, S-shaped, etc. shape. The output antenna 1-2 is an S-shaped platinum antenna with one end welded to the inner conductor 2 and one end welded to the helical wire by laser welding. Due to the high output power and large working ratio of the high-power pulse space traveling wave tube, the problem of output antenna 1-2 fusing failure is prone to occur. In actual use, the helical wire body 1-1 generates a microwave signal through its spiral structure, which is propagated along the helical wire body 1-1 of the antenna to the output antenna 1-2 part, that is, the extended tungsten strip. Multiple clamping rods 3 are tightly matched with the integrated antenna helical wire 1 by thermal expansion clamping, ensuring the physical stability of the antenna assembly under high temperature and high power conditions. During operation, the output antenna 1-2 is connected to the groove at the top of the inner conductor 2 by laser welding technology to form a stable physical connection.

[0037] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high-power pulse space traveling wave tube high-reliability output antenna structure, characterized in that: include: An antenna helix (1), comprising a helix body (1-1) and an output antenna (1-2), wherein the helix body (1-1) and the output antenna (1-2) are integrally formed; A tube shell (4) is provided with an inner conductor (2) inside, the output antenna (1-2) is inserted into a groove at the top of the inner conductor (2), and the helical wire body (1-1) is located at the center of the tube shell (4).

2. A high-power pulse space traveling wave tube high-reliability output antenna structure according to claim 1, characterized in that: A plurality of clamping rods (3) are arranged inside the antenna helical wire (1), and the plurality of clamping rods (3) are tightly clamped with the integrated antenna helical wire (1) by means of thermal expansion.

3. A high-power pulse space traveling wave tube high-reliability output antenna structure according to claim 2, characterized in that: The clamping rod (3) is of a herringbone structure, a conical structure or a cylindrical structure.

4. The high-power pulse space traveling wave tube high-reliability output antenna structure according to claim 1, characterized in that: The output antenna (1-2) is a section of tungsten tape extending from the end of the helical wire body (1-1).

5. The high-power pulse space traveling wave tube high-reliability output antenna structure according to claim 1, characterized in that: The top groove connection between the output antenna (1-2) and the output energy transmission inner conductor (2) is welded and fixed by using laser welding technology.

6. The high-power pulse space traveling wave tube high-reliability output antenna structure according to claim 2, characterized in that: The tube shell (4) is of circular design, and the plurality of clamping rods (3) are symmetrical to each other and are distributed at equal distances outside the spiral body (1-1).

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