Installation method for mounting optical antenna on large-aperture microwave antenna

Abstract

The invention discloses an installation method for mounting a large-aperture microwave antenna on an optical antenna, and relates to the field of spaceflight deep space exploration. The method comprises the following steps: firstly, welding a mounting steel plate in a microwave antenna center body, forming a hole in an antenna panel, then integrally hoisting an optical antenna and an adjusting bracket into the microwave antenna center body through a hoisting device, and mounting the optical antenna and the adjusting bracket on the mounting steel plate; and finally, the angle of the optical antenna is adjusted through the adjusting bracket, and a cable is arranged. The installation mode is simple, the structure is stable, and the electric axis of the microwave antenna and the optical axis of the optical antenna can be adjusted to be consistent. According to the invention, the microwave antenna can be upgraded and reformed, and a composite structure of the optical antenna and the microwave antenna is realized.

Description

Technical Field

[0001] The present invention relates to the field of deep space exploration, and in particular to a method for installing a large-aperture microwave antenna mounted with an optical antenna, which can be used in a deep space large-aperture antenna microwave laser composite system. Background Art

[0002] In the field of deep space exploration, microwave laser integrated measurement, control, and communication technology can solve the bottleneck problem of high-capacity data transmission and is an important research direction for future deep space exploration. Microwave laser composite antenna technology is one of the key technologies of microwave laser integrated measurement, control, and communication technology. The composite design of optical antennas and deep space large-aperture antennas needs to consider issues such as optical antenna obstruction, gravity effects, optical and radio frequency signal separation, and pointing stability. Especially for deep space large-aperture antennas, the requirements for antenna surface accuracy and pointing accuracy are relatively strict. After adding an optical antenna, the impact of the optical part on the original microwave system must be considered. Therefore, the composite design of deep space large-aperture antennas and optical antennas is more difficult.

[0003] At present, the composite forms of optical antennas and microwave antennas are mainly as follows:

[0004] (1) The optical antenna is fully composited with the main and secondary reflectors of the microwave antenna. The optical antenna uses a reflective optical lens, which is fully composited with the main and secondary reflectors of the microwave antenna and is placed at the center of the main surface of the microwave antenna. The disadvantage is that the secondary reflector of the microwave antenna has a large shielding effect on the optical antenna, and when the antenna aperture is large, its structural deformation easily leads to defocusing of the light spot.

[0005] (2) Multiple small-aperture optical arrays are combined with the main and secondary surfaces of the microwave antenna to decompose the single-aperture optical antenna into multiple small-aperture optical telescopes, which are distributed on the main reflective surface of the microwave antenna according to a certain layout to avoid obstruction by the secondary reflective surface. The disadvantage is that a mechanical adjustment mechanism is required to realize the formation of multiple optical beams. The adjustment process is too complicated and tedious, and the robustness of the composite structure is slightly poor.

[0006] (3) The optical array antenna is combined with the microwave antenna sub-reflector to solve the problems of the microwave antenna sub-reflector blocking the central optical antenna and the need for multiple optical lenses to be steered and adjusted by mechanical structures. The equivalent small-aperture array antenna is placed on the microwave antenna sub-reflector, and a hole is opened in the center of the sub-reflector to separate the synthetic optical signal and the microwave signal. The disadvantage is that the deformation and high-frequency vibration characteristics of the microwave antenna sub-reflector can easily affect the optical beam pointing. Summary of the Invention

[0007] In view of this, the present invention provides a method for mounting an optical antenna on a large-aperture microwave antenna. The present invention is suitable for large-aperture microwave antennas and has the advantages of low cost, good stability, and ease of engineering implementation. It can be used to upgrade and transform existing large-aperture microwave antennas for deep space exploration.

[0008] The object of the present invention is achieved like this:

[0009] A method for installing a large-aperture microwave antenna mounted on an optical antenna comprises the following steps:

[0010] Step 1: Turn the elevation position of the large-aperture microwave antenna to 0 degrees, with the antenna aperture facing the horizontal direction. The installer enters the center body of the large-aperture microwave antenna from the rear and welds the optical antenna mounting steel plate to the side wall where the center body of the microwave antenna intersects with the elevation fork arm.

[0011] Step 2: Turn the large-aperture microwave antenna to the skyward position, remove the antenna panel located on top of the optical antenna installation position on the large-aperture microwave antenna, or drill a hole in the antenna panel;

[0012] Step 3: Install an adjustment bracket for the optical antenna on the ground;

[0013] Step 4: Fix a hanging device on the optical antenna mounting steel plate with bolts. The hanging device extends beyond the antenna surface by removing the position of the antenna panel or the opening on the antenna panel.

[0014] Step 5: Using a hoisting device, hoist the optical antenna and the adjustment bracket as a whole into the center body of the large-aperture microwave antenna via a crane, and then install the optical antenna and the adjustment bracket as a whole onto the optical antenna mounting steel plate;

[0015] Step 6: Install a laser tracker on the large-aperture microwave antenna so that the laser tracker can simultaneously see the reflective prism on the optical antenna and the flange surface of the antenna center tube of the large-aperture microwave antenna;

[0016] Step 7: Adjust the angle of the optical antenna by adjusting the bracket and monitoring it with a laser tracker to make the axis of the optical antenna parallel to the axis of the antenna center tube of the large-aperture microwave antenna;

[0017] In step 8, the power cord, optical cable, and network cable of the optical antenna are wound into the tower base room of the large-aperture microwave antenna. The optical signal received by the optical antenna is transmitted to the detector in the room via the optical cable.

[0018] Optionally, in step 1, the optical antenna mounting steel plate is welded using intermittent welds.

[0019] Optionally, in step 2, the area of ​​the opening is no greater than 1 square meter.

[0020] Optionally, in step 3, the adjustment bracket has two ears, the optical antenna is connected to the two ears and has a degree of freedom of rotation with the line connecting the two ears as the rotation axis, the adjustment bracket has an adjustment bolt at a position below the front and rear ends of the optical antenna, and the front and rear ends of the optical antenna rest on the two adjustment bolts; the adjustment bolt is disposed in an upright box body, and a long slot parallel to the rotation axis is formed at the top of the box body. The adjustment bolt is inserted into the long slot and has the freedom to move up and down and slide along the long slot. The adjustment bolt has a nut above and below the long slot, and the long slot is clamped by the two nuts to fix the adjustment bolt;

[0021] In step 7, the angle of the optical antenna is adjusted by changing the position of the adjusting bolt. When the deviation between the axis of the optical antenna and the axis of the antenna center tube of the large-aperture microwave antenna is less than 0.002 degrees, the adjustment is completed. Tighten the two nuts to fix the adjusting bolt.

[0022] Optionally, in step 4, the lifting device includes a lifting pulley and a rope.

[0023] Optionally, each optical antenna includes a receiving mirror and a transmitting mirror, wherein the aperture of the receiving mirror is 400 mm and the aperture of the transmitting mirror is 200 mm;

[0024] There are two sidewall positions on the center body that intersect with the pitch fork arm, and the two optical antenna mounting steel plates are located at these two positions respectively; the two optical antennas are respectively mounted on their respective optical antenna mounting steel plates, and both optical antennas are installed according to steps 2 to 8.

[0025] The present invention has the following advantages:

[0026] (1) The optical antenna of the present invention has a simple installation method and a stable structure, which is conducive to the consistent pointing of the electric axis of the microwave antenna and the optical axis of the optical antenna.

[0027] (2) The optical antenna mounting bracket of the present invention has the ability to adjust the direction in two directions, which is convenient and flexible for adjusting the direction of the optical antenna.

[0028] (3) The design of the present invention facilitates the installation of optical upgrades on existing deep space large-aperture antennas, with minimal impact on microwave antenna performance indicators.

[0029] (4) The present invention combines the optical array antenna with the main reflective surface of the microwave antenna, and calibrates the consistency between the optical axis of the optical array antenna and the electrical axis of the microwave antenna, so that each optical antenna can achieve large-angle servo tracking to follow the microwave antenna for adjustment, as well as small-angle precision servo tracking. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1Schematic diagram of the installation position of the optical antenna on the 35-meter microwave antenna in an embodiment of the present invention.

[0031] Figure 2 yes Figure 1 A partial enlarged view of the installation location.

[0032] Figure 3 Schematic diagram of the positions of two optical antenna support steel plates from the microwave antenna aperture direction in an embodiment of the present invention.

[0033] Figure 4 It is a schematic diagram of symmetrically positioned holes on the reflecting surface of a 35-meter-diameter antenna in an embodiment of the present invention.

[0034] Figure 5 It is the XOZ plane simulation radiation pattern in the S band in the embodiment of the present invention without providing the spatial position for installing the optical antenna and after providing the spatial position for installing the optical antenna.

[0035] Figure 6 It is the XOZ plane simulation radiation pattern in the X-band embodiment of the present invention without setting the spatial position of the optical antenna for installation and after setting the spatial position of the optical antenna for installation.

[0036] Figure 7 It is the simulated radiation pattern of the XOZ plane in the Ka band in the embodiment of the present invention without setting the spatial position of the optical antenna for installation and after setting the spatial position of the optical antenna for installation.

[0037] Figure 8 Schematic diagram of adjusting the bracket in an embodiment of the present invention.

[0038] Figure 9 Schematic diagram of the antenna direction axes X-axis, Y-axis, and Z-axis in an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The present invention will be further described below with reference to the accompanying drawings and specific examples.

[0040] A method for installing a large-aperture microwave antenna mounted on an optical antenna comprises the following steps:

[0041] (1) Turn the elevation position of the large-aperture microwave antenna to 0 degrees, with the antenna aperture facing the horizontal direction. The installer enters the center body of the large-aperture microwave antenna from the back, and uses the side wall position where the center body of the microwave antenna and the elevation fork arm intersect as the welding position to weld the optical antenna installation steel plate.

[0042] When installing an optical antenna on a large-aperture microwave antenna, the field of view of the optical antenna is very small. It is installed in a place with the least dynamic deformation. The center body of the antenna is the load-bearing foundation of the main reflective surface of the antenna. The optical antenna is installed in a place where the deformation of the center body is the least affected.

[0043] The microwave laser composite antenna is equipped with two optical antennas, which are installed symmetrically at the center body. Each optical antenna supports both transmitting and receiving functions.

[0044] In this example, an optical antenna with a receiving mirror diameter of 400mm and a transmitting mirror diameter of 200mm is installed on a 35-meter large-aperture microwave antenna. The weight of a single optical antenna is about 130kg. When installing an optical antenna, in order not to affect the performance indicators of the microwave antenna, the installation position with the least deformation effect is selected. The antenna center body, which serves as the load-bearing foundation of the antenna, is the best choice. Specifically, taking the 35-meter antenna as an example, the antenna fork arm is supported on the antenna base through the pitch axis. The antenna center body connected to the fork arm is where the antenna deformation is the least. Figure 1 and Figure 2 .

[0045] Turn the antenna pitch position to the horizontal angle, and the installer enters the center body from the back of the antenna. Select the position in the center body where the gravity deformation has the least effect as the welding position for the installation steel plate, and weld the optical antenna installation steel plate to the side wall of the center body using intermittent welds.

[0046] The optical antenna is installed in the center of the microwave antenna. A steel plate is required for support. The rigid structure connection ensures the stability of the optical antenna and the microwave antenna. The location of the steel plate is referenced Figure 3 Marked steel plate position.

[0047] (2) Turn the large-aperture microwave antenna to the skyward position, remove the antenna panel on the large-aperture microwave antenna located on top of the optical antenna installation position, or drill a hole in the antenna panel.

[0048] The antenna opening is to prevent the laser signal from being blocked. According to the calculation of the 35-meter aperture antenna, the opening area of ​​1 square meter has a minimal impact on the performance of the microwave antenna. For microwave antennas, the main indicator of antenna performance is the antenna gain. A 35-meter standard parabolic antenna is simulated, and a Gaussian feed is used at the focus for simulated illumination. The XOZ surface antenna pattern is calculated using a program equivalent to the MLFMA full-wave algorithm, and the performance impact after the hole required to install the optical antenna is simulated. In order to install the optical transceiver antenna, an area of ​​1 square meter is opened symmetrically on the reflecting surface of the 35-meter aperture antenna. The standard surface reference after the installation hole is used Figure 4 .

[0049] Reference for the XOZ plane simulation pattern when the optical antenna space position is not specified for the S band and the optical antenna space position is specified for the S band Figure 5 Reference for X-band optical antenna installation spatial position not specified and XOZ surface simulation pattern after specifying the installation spatial position of the optical antenna Figure 6Reference for the XOZ plane simulation pattern when the optical antenna space position is not specified and the optical antenna space position is specified. Figure 7 The comprehensive radiation patterns of the three frequency bands show that the hole punched on the main surface of the 35-meter aperture microwave antenna for installing the optical communication antenna has no significant impact on the antenna gain performance.

[0050] (3) Install an adjustment bracket for the optical antenna on the ground.

[0051] The optical antenna is installed on the ground with an adjustment bracket. The optical antenna and adjustment bracket are hoisted together using a crane. The optical antenna pointing adjustment bracket is installed on the ground together with the optical antenna, which is convenient for operation and hoisted together to improve efficiency.

[0052] like Figure 8 As shown, the adjustment bracket has two ears, the optical antenna is connected to the two ears, and has the freedom of rotation with the line connecting the two ears as the rotation axis. The adjustment bracket has an adjustment bolt at a position below the front and rear ends of the optical antenna, and the front and rear ends of the optical antenna rest on the two adjustment bolts; the adjustment bolt is arranged in an upright box body, and a long groove parallel to the rotation axis is opened on the top of the box body. The adjustment bolt is inserted into the long groove and has the freedom of up and down movement and sliding along the long groove. There is a nut on the upper and lower sides of the long groove on the adjustment bolt, and the long groove is clamped by the two nuts to fix the adjustment bolt.

[0053] The adjustment bracket is fixed on the steel plate welded to the center of the antenna. This adjustment bracket has the ability to adjust the direction in two directions, that is, when the antenna aperture points to the sky, it has the ability to adjust in two directions, X and Y. Figure 9 , tighten the screws after adjustment is completed.

[0054] (4) A hanging device is fixed on the optical antenna mounting steel plate with bolts, and the hanging device extends out of the antenna surface through the position where the antenna panel is removed or the opening on the antenna panel.

[0055] The lifting device mainly includes lifting pulleys and ropes.

[0056] (5) Using a hoisting device, hoist the optical antenna and the adjustment bracket as a whole into the central body of the large-aperture microwave antenna via a crane, and then install the optical antenna and the adjustment bracket as a whole onto the optical antenna mounting steel plate.

[0057] (6) A laser tracker is installed on the antenna of the large-aperture microwave antenna so that the laser tracker can simultaneously see the reflecting prism on the optical antenna and the flange surface of the antenna center tube of the large-aperture microwave antenna.

[0058] (7) Adjust the angle of the optical antenna by adjusting the bracket and monitor it with a laser tracker to make the axis of the optical antenna parallel to the axis of the antenna center tube of the large-aperture microwave antenna.

[0059] When the deviation between the axis of the optical antenna and the axis of the antenna center tube of the large-aperture microwave antenna is less than 0.002 degrees, the adjustment is completed and the screws of the adjustment bracket are tightened.

[0060] (8) The power cord, optical cable and network cable of the optical antenna are sent into the tower base room of the large-aperture microwave antenna by winding. The optical signal received by the optical antenna is transmitted to the detector in the room through the optical cable.

[0061] The most important part of the microwave laser composite antenna design is the effective separation of microwave signals and optical signals. This conformal design ensures that the optical signal can be transmitted to the optical signal detector in the computer room without affecting the transmission of the microwave signal.

[0062] The microwave laser composite antenna features two optical antennas, mounted symmetrically on the center body. Each optical antenna performs both transmitting and receiving functions, with the transmitting and receiving mirrors integrated and mounted on a steel plate. Steel plates are located at two locations on the sidewall where the center body intersects the elevation fork arm, respectively, for mounting the optical antennas. The receiving antenna has an aperture of 400mm, while the transmitting antenna has an aperture of 200mm.

[0063] This method utilizes a composite design of an optical antenna and the microwave antenna's primary reflector. Mounting the optical antenna within the antenna's centerpiece eliminates the problem of obstruction by the microwave antenna's secondary reflector, facilitating the separation of optical and microwave signals. Furthermore, since the primary reflector exhibits minimal high-frequency vibration, it also enhances the optical antenna's pointing stability.

[0064] The optical antenna mounting bracket of the present invention has the ability to adjust the pointing direction in two directions, making it convenient and flexible to adjust the pointing direction of the optical antenna. Using this method, an optical antenna can be added to an existing deep-space large-aperture antenna, with minimal impact on the performance of the microwave antenna.

[0065] In summary, the present invention provides a simple installation method for the optical antenna, a stable structure, and easy alignment of the microwave antenna's electrical axis and the optical antenna's optical axis. The present invention can be used to upgrade and modify microwave antennas to achieve a composite structure of optical and microwave antennas.

Claims

1. A method for installing a large-aperture microwave antenna mounted with an optical antenna, characterized in that: The following steps are involved: Step 1: Turn the elevation position of the large-aperture microwave antenna to 0 degrees, with the antenna aperture facing the horizontal direction. The installer enters the center body of the large-aperture microwave antenna from the rear and welds the optical antenna mounting steel plate to the side wall where the center body of the microwave antenna intersects with the elevation fork arm. Step 2: Turn the large-aperture microwave antenna to the skyward position, remove the antenna panel located on top of the optical antenna installation position on the large-aperture microwave antenna, or drill a hole in the antenna panel; Step 3: Install an adjustment bracket for the optical antenna on the ground; Step 4: Fix a hanging device on the optical antenna mounting steel plate with bolts. The hanging device extends beyond the antenna surface by removing the position of the antenna panel or the opening on the antenna panel. Step 5: Using a hoisting device, hoist the optical antenna and the adjustment bracket as a whole into the center body of the large-aperture microwave antenna via a crane, and then install the optical antenna and the adjustment bracket as a whole onto the optical antenna mounting steel plate; Step 6: Install a laser tracker on the large-aperture microwave antenna so that the laser tracker can simultaneously see the reflective prism on the optical antenna and the flange surface of the antenna center tube of the large-aperture microwave antenna; Step 7: Adjust the angle of the optical antenna by adjusting the bracket and monitoring it with a laser tracker to make the axis of the optical antenna parallel to the axis of the antenna center tube of the large-aperture microwave antenna; In step 8, the power cord, optical cable, and network cable of the optical antenna are wound into the tower base room of the large-aperture microwave antenna. The optical signal received by the optical antenna is transmitted to the detector in the room via the optical cable.

2. The method for installing a large-aperture microwave antenna mounted optical antenna according to claim 1, characterized in that: In step 1, the optical antenna mounting steel plate is welded using intermittent welds.

3. The method for installing a large-aperture microwave antenna mounted optical antenna according to claim 1, characterized in that: In step 2, the area of ​​the opening is no greater than 1 square meter.

4. The method for installing a large-aperture microwave antenna mounted optical antenna according to claim 1, characterized in that: In step 3, the adjustment bracket has two ears, the optical antenna is connected to the two ears and has the freedom of rotation about the line connecting the two ears as the rotation axis, and the adjustment bracket has an adjustment bolt below the front and rear ends of the optical antenna, respectively, and the front and rear ends of the optical antenna abut against the two adjustment bolts; the adjustment bolt is disposed in an upright box body, and a long slot parallel to the rotation axis is formed at the top of the box body. The adjustment bolt is inserted into the long slot and has the freedom of upward and downward movement and sliding along the long slot. The adjustment bolt has a nut above and below the long slot, and the long slot is clamped by the two nuts to fix the adjustment bolt; In step 7, the angle of the optical antenna is adjusted by changing the position of the adjusting bolt. When the deviation between the axis of the optical antenna and the axis of the antenna center tube of the large-aperture microwave antenna is less than 0.002 degrees, the adjustment is completed. Tighten the two nuts to fix the adjusting bolt.

5. The method for installing a large-aperture microwave antenna mounted optical antenna according to claim 1, characterized in that: In step 4, the hoisting device includes a hoisting pulley and a rope.

6. The method for installing a large-aperture microwave antenna mounted optical antenna according to claim 1, characterized in that: Two optical antennas are installed on the large-aperture microwave antenna. Each optical antenna includes a receiving mirror and a transmitting mirror. The aperture of the receiving mirror is 400mm, and the aperture of the transmitting mirror is 200mm. There are two sidewall positions on the center body that intersect with the pitch fork arm, and the two optical antenna mounting steel plates are located at these two positions respectively; the two optical antennas are respectively mounted on their respective optical antenna mounting steel plates, and both optical antennas are installed according to steps 2 to 8.

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