V-frequency-band satellite-borne waveguide rotary joint

Abstract

The invention provides a V-frequency-band satellite-borne waveguide rotary joint. A mode converter of the rotary joint comprises an input interface; the first transition section comprises a tuning boss, a power dividing structure and a matching structure, the tuning boss is of a stepped structure, the power dividing structure comprises a power dividing plane, a first power dividing wing and a second power dividing wing, the first power dividing wing and the second power dividing wing extend towards the two sides from the power dividing plane and are connected to the matching structure after being bent downwards, and the matching structure is a strip-shaped cube; the transmission circular waveguide is connected with the matching structure, the first power dividing wing and the second power dividing wing, and the extension direction of the matching structure is perpendicular to the extension direction of the transmission circular waveguide; the second transition section is provided with a structure symmetrical to the first transition section; and the output interface has a structure symmetrical to that of the input interface. According to the waveguide rotary joint, the problem that the radial size of the waveguide rotary joint is too large is solved through the downward bending power division structure.

Description

Technical Field

[0001] The invention relates to a V-band satellite carrier-guided rotary joint for microwave communication. Background Art

[0002] In microwave communications, there is often a contradiction between discontinuous mechanical structures and continuous microwave signals. For example, in a mechanical movable antenna, the signal needs to pass through the scanning axis to be transmitted from the feed part to the output part. Rotary joints are a common solution to this problem. In low-frequency and low-power scenarios, coaxial rotary joints have been widely used below the L band because the TEM waves propagating in the coaxial line naturally have rotational symmetry. As the operating frequency of satellite-borne antennas gradually develops towards the Ka and V bands, the shortcomings of high insertion loss and low power capacity of coaxial lines in the high-frequency field have gradually become prominent.

[0003] The existing methods for solving high-frequency rotation joints above the Ka band are mainly divided into two technical paths:

[0004] 1. Continue to use the coaxial transmission structure and further reduce the insertion loss of the coaxial transmission mode and improve the power capacity by developing new dielectric materials;

[0005] 2. Based on the characteristics of low insertion loss and high power capacity of waveguide components and the rotational symmetry of the TM01 mode in the circular waveguide, a full-waveguide mode rotary joint is designed. The existing technologies include a satellite-borne V-band broadband waveguide rotary joint using a coaxial mode converter structure (application number 202311577533.1) and a Ka-band high-power waveguide rotary joint using a full-waveguide structure (application number 200910210147.2).

[0006] The main disadvantages of using coaxial mode converter revolute joints are:

[0007] 1. The insertion loss of the coaxial type mode converter is high

[0008] On the one hand, the wave in the transmission channel experiences the rectangular waveguide TE10 mode - rotor coaxial dielectric sleeve TEM mode - rotor circular waveguide TM01 mode - rotor coaxial dielectric sleeve TEM mode - rectangular waveguide TE10 mode. The mode conversion form is complex and the insertion loss is high during the conversion process.

[0009] On the other hand, the coaxial structure transmits the TEM mode and suppresses the TE11 mode, and its size is related to the frequency. The high-frequency coaxial structure has a small physical size and high processing progress requirements, and the standing wave, insertion loss and power capacity indicators are further reduced.

[0010] 2. Coaxial type mode converters have poor thermal environment tolerance

[0011] The coaxial structure is composed of a metal inner conductor, a dielectric, and a metal outer conductor. The operating temperature of the satellite-borne rotary joint can reach -40 to 70°C. Within a large temperature range, due to the inconsistent thermal expansion coefficients of the metal and the dielectric, the dielectric is squeezed and deformed, the impedance characteristics and standing wave characteristics of the coaxial structure are offset, and the overall electrical performance is reduced.

[0012] The main disadvantages of existing full waveguide structure rotation joints are:

[0013] 1. Waveguide mode converter has narrow bandwidth

[0014] Since the current waveguide mode converter uses a matching ring to match the square waveguide and circular waveguide in the transition stage, the working bandwidth of the mode converter is relatively narrow, about 8%.

[0015] 2. The physical size of the dual-channel input Y branch is large

[0016] like Figure 1 As shown in the figure, since the connection between the Y branch and the circular waveguide is located at the leftmost end of the entire structure, the main structure of the Y branch is all distributed on the right side of the circular waveguide. During the rotation of the rotary joint, the entire Y rotates directly around the circular waveguide, resulting in an oversized axial dimension of the rotary joint. Summary of the invention

[0017] The purpose of the present invention is to solve the problems of high insertion loss, low power capacity and difficult processing of rotary joints based on coaxial structures within the high-frequency working range, and to provide a full-waveguide rotary joint. By bending the power splitter structure downward, the problem of excessive radial dimensions of traditional waveguide rotary joints is optimized. The shaft system structure is suitable for space environments, and the problem of decreased electrical performance of rotary joints under high and low temperature conditions is solved.

[0018] The present application provides a V-band satellite carrier guided rotation joint, comprising:

[0019] The first rotating component comprises a bearing inner ring and a first rotating arm which are relatively fixedly connected together, wherein the inner ring of the bearing has a cylindrical cavity extending along the central axis of the bearing, and the first rotating arm has a square cavity inside;

[0020] The second rotating component comprises a bearing outer ring and a second rotating arm which are relatively fixedly connected together, the bearing outer ring has a cavity for accommodating the bearing inner ring of the first rotating component, and the second rotating arm has a square cavity inside;

[0021] The inner ring of the bearing is nested inside the outer ring of the bearing, so that the first rotating component and the second rotating component can rotate freely around the central axis of the bearing to realize the rotation function of the rotary joint.

[0022] The first square cavity inside the first rotating arm, the cylindrical cavity inside the inner ring of the bearing, and the second square cavity inside the second rotating arm are connected in sequence, and the formed cavity constitutes a mode converter of the waveguide.

[0023] The mode converter includes:

[0024] Input interface, in the form of a rectangular waveguide;

[0025] The first transition section includes a tuning boss, a power division structure, and a matching structure. The tuning boss is a stepped structure. The power division structure includes a power division plane, a first power division wing, and a second power division wing. The first power division wing and the second power division wing extend from the power division plane to both sides and are bent downward to be connected to the matching structure. The matching structure is a strip-shaped cube.

[0026] A transmission circular waveguide is connected to the matching structure, the first power splitting wing, and the second power splitting wing, and the extending direction of the matching structure is perpendicular to the extending direction of the transmission circular waveguide;

[0027] A second transition section having a structure symmetrical to the first transition section;

[0028] The output interface has a structure symmetrical to the input interface.

[0029] According to at least one embodiment of the present application, the tuning boss is a stepped structure extending along a first direction, the first power splitting wing and the second power splitting wing extend to both sides from the power splitting plane and bend in a second direction, and the first direction is perpendicular to the second direction.

[0030] According to at least one embodiment of the present application, the input interface is a standard waveguide interface.

[0031] According to at least one embodiment of the present application, the transition and matching between the power splitter structure and the standard waveguide are achieved by adjusting the lateral and longitudinal dimensions of the matching structure.

[0032] According to at least one embodiment of the present application, the bandwidth of the mode converter is adjusted by adjusting the size of the tuning boss in the transition section.

[0033] According to at least one embodiment of the present application, an electromagnetic wave is input through an input interface in a rectangular TE01 mode, separated into two equal-amplitude parts at a power division plane, and input into a matching structure through a first power division wing and a second power division wing, respectively. The matching structure converts the electromagnetic wave from a TE10 mode in a rectangular waveguide into a TM01 mode in a circular waveguide, so that the transmission state of the electromagnetic wave does not change during the rotation of the input interface and the output interface around the circular waveguide.

[0034] According to at least one embodiment of the present application, a choke is further included. The choke is formed by a gap between a bearing inner ring and a bearing outer ring. The choke uses the outer wall of the bearing inner ring as the choke inner wall and the bearing outer ring as the choke outer wall.

[0035] According to at least one embodiment of the present application, the mode converter is composed of a square waveguide, a circular waveguide and a transition section structure, and is a four-port waveguide component, and each port is in the form of a rectangular waveguide.

[0036] According to at least one embodiment of the present application, the power division component composed of the tuning boss, the power division structure, and the matching structure matches the frequency band and impedance of the mode converter.

[0037] According to at least one embodiment of the present application, the first rotating component and the second rotating component are rotatably connected via an angular contact bearing and a deep groove ball bearing.

[0038] The rotary joint provided in the present application has a rectangular waveguide TE10-circular waveguide TM01 mode converter structure with a relative bandwidth of 10%, a standing wave ≤1.05, and an insertion loss ≤0.05dB, which can reduce the radial size of the rotary joint, reduce the antenna insertion loss, and improve the environmental adaptability of the satellite-borne rotary joint. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The following will further explain the above characteristics, technical features, advantages and implementation methods of the present application in a clear and understandable manner through the description of the preferred embodiments and in combination with the accompanying drawings. The following drawings are only intended to illustrate and explain the present application, and do not limit the scope of the present application. Among them:

[0040] Figure 1 The rotating process of the rotating joint in the prior art is shown;

[0041] Figure 2 is a cross-sectional perspective view of a waveguide rotary joint;

[0042] Figure 3 is a cross-sectional plan view of the waveguide rotation joint;

[0043] Figure 4 A mode converter according to a specific embodiment of the present application;

[0044] Figure 5 It is a structural schematic diagram of the transition section;

[0045] Figure 6 A schematic diagram of the matching structure. DETAILED DESCRIPTION

[0046] In order to have a clearer understanding of the technical features, purposes and effects of the present application, the specific implementation methods of the present application are now described with reference to the accompanying drawings.

[0047] An embodiment of the present application provides a V-band satellite carrier guided rotation joint such as Figure 2 and Figure 3 As shown, Figure 2 This is a cross-sectional stereogram of the waveguide rotary joint. Figure 3 is the cross-sectional plan view of the waveguide rotation joint. Figure 2 and Figure 3 As shown, the V-band satellite carrier guidance rotary joint includes:

[0048] The first rotating component 1 comprises a bearing inner ring 11 and a first rotating arm 12 which are relatively fixedly connected together, the bearing inner ring 11 has a cylindrical cavity 13 extending along the bearing center axis AA, and the first rotating arm 12 has a square cavity 14;

[0049] The second rotating component 2 comprises a bearing outer ring 21 and a second rotating arm 22 which are relatively fixedly connected together. The bearing outer ring 21 has a cavity for accommodating the bearing inner ring 11 of the first rotating component 1 , and the second rotating arm 22 has a square cavity 24 inside.

[0050] The bearing inner ring 11 is nested inside the bearing outer ring 21 , so that the first rotating component 1 and the second rotating component 2 can rotate freely around the bearing center axis AA to realize the rotation function of the rotary joint.

[0051] like Figure 2 and Figure 3 As shown, the first square cavity 14 inside the first rotating arm 12, the cylindrical cavity 13 inside the bearing inner ring 11, and the second square cavity 24 inside the second rotating arm 22 are connected in sequence to form a Figure 4 The cavity shown constitutes a mode converter of the waveguide.

[0052] The mode converter has a rectangular waveguide and TE10-circular waveguide TM01 with a relative bandwidth of 10%, a standing wave of ≤1.05, and an insertion loss of ≤0.05dB. The mode converter is composed of a square waveguide, a circular waveguide and a transition section structure. It is a four-port waveguide component. Each port is in the form of a rectangular waveguide, which is divided into an input port and an output port. The input port inputs electromagnetic waves of equal amplitude and inverse phase, where the main mode of the rectangular waveguide is the TE10 mode and the other high-order modes excited by the structural discontinuity are differential modes, which cancel each other out due to the inverse input. By adjusting the matching and transition structure, the mode conversion efficiency, standing wave and insertion loss of the mode converter within the working frequency band meet the requirements of the rotary joint.

[0053] like Figure 4 As shown, the mode converter according to a specific embodiment of the present application includes:

[0054] The input interface 5 is in the form of a rectangular waveguide and can be a standard waveguide interface;

[0055] The first transition section 6 has a specific structure as follows Figure 5 As shown, it includes a tuning boss 61, a power division structure 62, and a matching structure 63; the tuning boss 61 is a stepped structure extending along the X direction; the power division structure 62 includes a power division plane 620, a first power division wing 621 and a second power division wing 622, the first power division wing 621 and the second power division wing 622 extend from the power division plane 620 to both sides and bend downward (i.e., toward Figure 5 After being bent in the Y direction as shown in FIG. , it is connected to the matching structure 63; the matching structure 63 is as shown in FIG. Figure 6 As shown, it is a strip cube;

[0056] The transmission circular waveguide 7 is connected to the matching structure 63 and the first power splitting wing 621 and the second power splitting wing 622 of the power splitting structure 62, and the extending direction of the matching structure 63 is perpendicular to the extending direction of the transmission circular waveguide 7;

[0057] The second transition section 8 has a symmetrical structure with the first transition section 6;

[0058] The output interface 9 has a structure symmetrical to that of the input interface 5 .

[0059] The transition and matching between the power splitter structure 62 and the BJ500 standard waveguide can be completed by adjusting the lateral and longitudinal dimensions of the matching structure 63. The bandwidth of the mode converter can be effectively widened by adjusting the dimensions of the tuning boss 61 in the transition section.

[0060] By adjusting the size and position of the tuning boss 61, the power division function can be realized and matched.

[0061] The tuning boss 61, the power division structure 62 and the matching structure 63 constitute a power division component that matches the frequency band and impedance of the mode converter. By making the power division structure 62 adopt a power division wing configuration that extends to both sides and bends downward, the radial size of the rotating joint can be greatly reduced.

[0062] In the waveguide rotary joint provided in this embodiment, the electromagnetic wave is input through the input interface 5 in a rectangular TE01 mode, and is separated into two equal-amplitude parts at the power splitting plane 620, and is input to the matching structure 63 through the first power splitting wing 621 and the second power splitting wing 622 respectively. The matching structure 63 converts the electromagnetic wave from the TE10 mode in the rectangular waveguide into the TM01 mode in the circular waveguide 7. Since the electromagnetic wave input by the matching structure 63 is an equal-amplitude anti-phase electromagnetic wave, the TE10 mode is enhanced as a closed mode, and other high-order modes caused by discontinuity are suppressed as differential modes, the structure further enhances the mode conversion efficiency and reduces the insertion loss.

[0063] Since the TM01 wave in the circular waveguide 7 has rotational symmetry, the electromagnetic wave transmission state does not change during the rotation of the input interface 5 and the output interface 9 around the circular waveguide, thereby achieving the function of discontinuous mechanical structure but continuous electromagnetic propagation.

[0064] The V-band satellite carrier transmission rotary joint provided in this embodiment also has a circular waveguide choke structure, which can effectively reduce the insertion loss of the rotary joint. Due to the mechanical discontinuity of the rotary switch, the transmission circular waveguide is composed of two circular waveguides with a gap. If the gap is not processed, it will cause leakage wave phenomenon, increasing the insertion loss of the rotary joint.

[0065] like Figure 2 and Figure 3 As shown, the V-band satellite carrier carrier rotary joint provided in this embodiment also includes a choke 31. The choke 31 is formed by a gap between the bearing inner ring 11 and the bearing outer ring 21. The choke 31 directly uses the outer wall of the bearing inner ring 11 as the inner wall of the choke, and uses the bearing outer ring 21 as the outer wall of the choke, realizing a structural and functional integrated design.

[0066] The satellite-borne guidance rotary joint provided in this embodiment adopts an improved rotary joint shaft system design, which can improve the environmental adaptability of the satellite-borne rotary joint.

[0067] The high-frequency rotary joint in the space environment has a wide operating temperature range. Due to the inconsistency between the joint material and the bearing material, thermal deformation is obvious, resulting in a decrease in the performance of the rotary joint. Figure 3 As shown, the rotary joint shaft system design of the present invention adopts the form of double bearings + bearing support cylinder, wherein the part close to the circular waveguide interface is an angular contact bearing 33, and the part away from the circular waveguide interface is a deep groove ball bearing 32, and the inner rings of the two bearings are both interference fit. Since the angular contact bearing 33 can bear a certain axial load, the deep groove ball shaft 32 cannot bear the axial load and has axial clearance, when the rotary joint produces thermal deformation, the deformation is transmitted to the deep groove ball bearing part, ensuring that the change in the circular waveguide gap is small, and preventing the electrical performance of the rotary joint from decreasing.

[0068] The present application provides a V-band rotary joint for satellite use, whose operating frequency band can cover 46.5-51.5, relative bandwidth 10.2%, standing wave ≤1.1, insertion loss: ≤0.1dB. During the rotation process, the standing wave and insertion loss change range is less than 5%; the operating temperature is -20-60℃; the working environment can be vacuum.

[0069] The above description is only an illustrative embodiment of the present application and is not intended to limit the scope of the present application. Any equivalent changes, modifications and combinations made by any technician in the field without departing from the concept and principle of the present application shall fall within the scope of protection of the present application.

Claims

1. A V-band satellite carrier guided rotary joint, comprising: The first rotating component comprises a bearing inner ring and a first rotating arm which are relatively fixedly connected together, wherein the inner ring of the bearing has a cylindrical cavity extending along the central axis of the bearing, and the first rotating arm has a square cavity inside; The second rotating component comprises a bearing outer ring and a second rotating arm which are relatively fixedly connected together, the bearing outer ring has a cavity for accommodating the bearing inner ring of the first rotating component, and the second rotating arm has a square cavity inside; The inner ring of the bearing is nested inside the outer ring of the bearing, so that the first rotating component and the second rotating component can rotate freely around the central axis of the bearing to realize the rotation function of the rotary joint. The first square cavity inside the first rotating arm, the cylindrical cavity inside the inner ring of the bearing, and the second square cavity inside the second rotating arm are connected in sequence, and the formed cavity constitutes a mode converter of the waveguide. The mode converter includes: Input interface, in the form of a rectangular waveguide; The first transition section includes a tuning boss, a power division structure, and a matching structure. The tuning boss is a stepped structure. The power division structure includes a power division plane, a first power division wing, and a second power division wing. The first power division wing and the second power division wing extend from the power division plane to both sides and are bent downward to be connected to the matching structure. The matching structure is a strip-shaped cube. A transmission circular waveguide is connected to the matching structure, the first power splitting wing, and the second power splitting wing, and the extending direction of the matching structure is perpendicular to the extending direction of the transmission circular waveguide; A second transition section having a structure symmetrical to the first transition section; The output interface has a structure symmetrical to the input interface.

2. The rotary joint according to claim 1, wherein: The tuning boss is a stepped structure extending along a first direction. The first power splitting wing and the second power splitting wing extend from the power splitting plane to both sides and bend in a second direction. The first direction is perpendicular to the second direction.

3. The rotary joint according to claim 1, wherein: The input interface is a standard waveguide interface.

4. The rotary joint according to claim 1, wherein: By adjusting the lateral and longitudinal dimensions of the matching structure, the transition and matching between the power division structure and the standard waveguide are completed.

5. The rotary joint according to claim 1, wherein: By adjusting the size of the tuning boss in the transition section, the bandwidth of the mode converter is adjusted.

6. The rotary joint according to claim 1, wherein: The electromagnetic wave is input through the input interface in a rectangular TE01 mode, and is separated into two equal-amplitude parts at the power splitting plane, and input into the matching structure through the first power splitting wing and the second power splitting wing respectively. The matching structure converts the electromagnetic wave from the TE10 mode in the rectangular waveguide into the TM01 mode in the circular waveguide, so that the transmission state of the electromagnetic wave does not change during the rotation of the input interface and the output interface around the circular waveguide.

7. The rotary joint according to claim 1 further comprises a choke, which is formed by a gap between the inner ring of the bearing and the outer ring of the bearing, and the choke uses the outer wall of the inner ring of the bearing as the inner wall of the choke and the outer wall of the bearing as the outer wall of the choke.

8. The rotary joint according to claim 1, wherein: The mode converter is composed of a square waveguide, a circular waveguide and a transition section structure, and is a four-port waveguide component, and each port is in the form of a rectangular waveguide.

9. The rotary joint according to claim 1, wherein: The power division component composed of the tuning boss, the power division structure and the matching structure matches the frequency band and impedance of the mode converter.

10. The rotary joint according to claim 1, wherein: The first rotating component and the second rotating component are rotatably connected via an angular contact bearing and a deep groove ball bearing.

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