Satellite phased-array antenna formed wave beam in-orbit sun pointing providing method

Abstract

The invention discloses a method for providing sun pointing in orbit by a beam formed by a satellite phased-array antenna. The method comprises the following steps: step S1, fixed wide-angle receiving; s2, phased array wide-beam coarse scanning is carried out; s3, phased array narrow beam fine scanning is carried out; s4, when the antenna noise temperature in a narrow beam in phased array narrow beam fine scanning reaches a set threshold 3, it is judged that the narrow beam points to the sun, and sun pointing data is provided for a satellite service computer; and S5, when it is judged that the narrow beam points to the sun, a phased array narrow beam jitter tracking technology is used, sun pointing information is continuously provided, the sensing capacity is provided for the satellite in-orbit attitude, the method is combined with an existing broadband communication load phased array antenna, the number of antenna arrays is not increased or only a small number of antenna arrays is increased, and in a beam forming mode, the satellite in-orbit attitude is obtained. And the receiving beam range precision comparable to that of a sun sensor is realized.

Description

Technical Field

[0001] The present invention relates to the field of satellite communication payload and attitude control, and in particular to a method for a satellite phased array antenna to form a beam and provide sun pointing in orbit. Background Art

[0002] Satellites are high-tech products that integrate numerous sensors and payloads. If the payloads can realize the functions of some sensors, compensate for their blind spots or provide backups, or even achieve data fusion to improve the performance and accuracy of the system, it will reduce costs and increase efficiency of the satellite platform, which is extremely valuable for commercial aerospace, which is relatively sensitive to prices.

[0003] Satellite phased array communication payload refers to the establishment of uplink and downlink channels between the satellite and the ground station or terminal equipment to transmit data and various remote control commands or various parameter information. It is one of the most important functions of the satellite. Its antenna beam pointing angle is large, ensuring that the satellite can communicate with the ground in different postures.

[0004] Phased array antennas form beams in space by changing the phase of each antenna subarray. The subarray phase usually uses a phase shifter, which has a fast agility time and can achieve rapid scanning of the beam in the airspace.

[0005] As a broadband microwave random signal emission source, the sun can be regarded as a stable noise source. When the antenna is pointed at the sun, the noise level of the received signal is the highest. Currently, there is no suitable satellite phased array antenna to form a beam and provide sun pointing technology in orbit. Summary of the invention

[0006] In view of the shortcomings of the prior art, the present invention provides a method for satellite phased array antenna to form beams and provide sun pointing in orbit. The method combines the existing broadband communication payload phased array antenna, does not increase or only increases a small number of antenna arrays, and achieves a receiving beam range accuracy comparable to that of a solar sensor through beam forming. It can serve as a backup for the solar sensor in the attitude control safety mode; in the working mode, it can compensate for the blind spots of the solar sensor and star sensor, and fuse their data to improve the attitude perception capability in orbit.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A method for forming a beam by a satellite phased array antenna to provide sun pointing in orbit comprises the following steps:

[0009] Step S1: Fixed wide-angle reception, when the antenna noise temperature of a single array in the multiplexed broadband phased array reaches a set threshold 1, it is determined that the single array is pointing to the sun;

[0010] Step S2: phased array wide beam coarse scanning, using part of the array in the phased array to form a wide beam, when the antenna noise temperature in the wide beam reaches the set threshold 2, it is determined that the wide beam is pointing to the sun;

[0011] Step S3: phased array narrow beam fine scanning, using one beam in the phased array to perform a spatial search at the wave position pointing to the sun in the phased array wide beam coarse scanning;

[0012] Step S4: when the antenna noise temperature in the narrow beam of the phased array narrow beam fine scanning reaches the set threshold 3, it is determined that the narrow beam is pointing to the sun, and the sun pointing data is provided to the satellite service computer;

[0013] Step S5: After determining that the narrow beam is pointing to the sun, the phased array narrow beam jitter tracking technology is used to continuously provide sun pointing information to provide perception capability for the satellite's in-orbit attitude.

[0014] As a further solution of the present invention, in step S1, the calculation process of threshold 1 is: Where Ta(x,y) is the antenna noise temperature function, T B (ξ,ζ) is the brightness temperature of the sun; A is the power directivity diagram of a single-element phased array antenna; e is the effective area of ​​the antenna.

[0015] As a further solution of the present invention, in step S2, the calculation process of threshold 2 is: Where Ta(x,y) is the antenna noise temperature function, T B (ξ,ζ) is the brightness temperature of the sun; A is the power directivity diagram of the phased array wide beam antenna; e is the effective area of ​​the antenna.

[0016] As a further scheme of the present invention, the specific search process of step S3 is: setting an initial angle according to the wave position, and the satellite service computer corrects the pitch angle as the starting pitch surface adjustment point; performing a small-angle scan in azimuth in the wave position; judging whether the antenna noise temperature increases; when the antenna noise temperature increases, the azimuth / pitch maintains the current position and performs a step search nearby; when the antenna noise temperature does not increase, judging whether the azimuth has completed the wave position scan; when the azimuth has completed the wave position scan, performing a small-angle scan in pitch; judging whether the pitch has completed the wave position scan; when the pitch has not completed the wave position scan, returning to performing a small-angle scan in azimuth in the wave position; when the pitch has completed the wave position scan, it indicates that the pointing is lost, and returning to step S2 for a coarse scan again.

[0017] As a further solution of the present invention, the calculation process of the threshold 3 is: Where Ta(x,y) is the antenna noise temperature function, T B(ξ,ζ) is the brightness temperature of the sun; A is the power directivity diagram of the phased array narrow beam antenna; e is the effective area of ​​the antenna.

[0018] As a further solution of the present invention, step S1 specifically includes multiplexing a single array in the broadband phased array to perform background noise measurement and analysis. By combining the solar flux in the frequency band and its rate of change over time, when the antenna noise temperature of the single array reaches a set threshold 1, it is determined that the single array is pointing to the sun.

[0019] As a further solution of the present invention, step S2 specifically includes using part of the arrays in the phased array to form a wide beam, setting the beam width and the wave position according to the scanning time requirement, scanning according to the wave position setting, combining the solar flux in the frequency band and its rate of change over time, and when the antenna noise temperature in the wide beam reaches the set threshold 2, it is determined that the wide beam is pointing to the sun.

[0020] As a further solution of the present invention, the array factor calculation process of the phased array wide beam is as follows: in is the array factor of the planar array, M and N are the total number of antenna radiating units in the X-axis and Y-axis directions of the phased array, and the distance between the unit and the adjacent unit at any position (m, n) in the XY plane is d x and d y , the unit excitation is represented by a mn .

[0021] As a further solution of the present invention, the calculation process of the array factor of the phased array narrow beam is as follows: in is the array factor of the planar array, M and N are the total number of antenna radiating units in the X-axis and Y-axis directions of the phased array, and the distance between the unit and the adjacent unit at any position (m, n) in the XY plane is d x and d y , the unit excitation is represented by a mn .

[0022] The present invention has the following beneficial effects:

[0023] The present invention provides a method for satellite phased array antenna to form a beam and provide solar pointing in orbit. Based on the existing broadband communication payload phased array antenna, the method achieves a receiving beam range accuracy comparable to that of a solar sensor through beam forming and solar noise detection, thereby enabling the satellite phased array antenna to form a beam and provide solar pointing in orbit.

[0024] In order to more clearly illustrate the structural features and effects of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic flow chart of a method for a satellite phased array antenna to form a beam and provide sun pointing in orbit is provided in an embodiment of the present invention.

[0026] Figure 2 A schematic diagram of the wave position of a phased array wide beam scanning according to the wave position provided in an embodiment of the present invention.

[0027] Figure 3 A schematic diagram of the implementation flow of a method for forming a beam with a satellite phased array antenna to provide sun pointing in orbit is provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0028] The present invention will be further explained below in conjunction with the accompanying drawings and related knowledge, and described clearly and completely. Obviously, the described application is only a part of the embodiments of the present invention, rather than all the embodiments.

[0029] Reference Figure 1-Figure 3 As shown, the present invention provides a method for satellite phased array antenna to form a beam and provide solar pointing in orbit, comprising the following steps: Step S1: Fixed wide-angle reception, through the antenna noise temperature of a single array in the multiplexed broadband phased array reaches the set threshold 1, determine that the single array is pointing to the sun; specifically, a single array in the multiplexed broadband phased array is subjected to background noise measurement and analysis, combined with the solar flux in the frequency band and its rate of change over time, when the antenna noise temperature of the single receiving array reaches the set threshold 1, determine that the single receiving array is pointing to the sun. Here, the satellite attitude sensor needs to be used to determine the pointing position of the phased array, combined with the characteristics of the solar broadband noise, to eliminate the same-frequency interference source; at this time, the phased array can perform the communication load function normally;

[0030] Step S2: Phased array wide beam coarse scan, using part of the array in the phased array to form a wide beam, when the antenna noise temperature of the wide beam reaches the set threshold 2, it is determined that the wide beam is pointing to the sun; specifically, to obtain more accurate sun pointing, use part of the array in the phased array to form a wide beam, set the beam width and wave position according to the scanning time requirements, scan according to the wave position setting, combine the solar flux in the frequency band and its rate of change over time, when the antenna noise temperature in the wide beam reaches the set threshold 2, it is determined that the wide beam is pointing to the sun. Here, the satellite attitude sensor needs to be used to determine the pointing position of the phased array, combined with the characteristics of the solar broadband noise, to eliminate the same-frequency interference source;

[0031] Step S3: phased array narrow beam fine scanning, using one beam in the phased array, and performing a spatial search on the wave position pointing to the sun in the phased array wide beam coarse scanning. Specifically, one beam in the phased array is used, and a beam width comparable to that of the sun sensor is set, and a spatial search is performed on the wave position searched in step S2;

[0032] Step S4: When the antenna noise temperature reaches the set threshold 3 during the phased array narrow beam fine scanning, it is determined that the narrow beam points to the sun, and the solar pointing data is provided to the satellite service computer. Since the sun is a non-point source, when the method of the present invention is used to provide solar pointing, the setting of the beam width of the narrow beam will have a certain impact on the result, specifically, the wider the beam width, the better the solar pointing performance;

[0033] Step S5: After determining that the narrow beam is pointing to the sun, the phased array narrow beam jitter tracking technology is used to continuously provide sun pointing information to provide perception capability for the satellite's in-orbit attitude.

[0034] In the present invention, the specific process of calculating threshold 1 is to combine the power directivity diagram of a single-element antenna of a phased array, and the calculation formula is: Where Ta(x,y) is the antenna noise temperature function, T B (ξ,ζ) is the brightness temperature of the sun; A is the power directivity diagram of a single-element phased array antenna; e is the effective area of ​​the antenna.

[0035] In the present invention, the array factor of the phased array wide beam is calculated The calculation formula is: in is the array factor of the planar array, M and N are the total number of antenna radiating units in the X-axis and Y-axis directions of the phased array, and the distance between the unit and the adjacent unit at any position (m, n) in the XY plane is d x and d y , the unit excitation is represented by a mn .

[0036] In the present invention, the array factor of the phased array narrow beam is calculated The calculation formula is: in is the array factor of the planar array, M and N are the total number of antenna radiating units in the X-axis and Y-axis directions of the phased array, and the distance between the unit and the adjacent unit at any position (m, n) in the XY plane is d x and d y , the unit excitation is represented by a mn .

[0037] In the present invention, the process of calculating threshold 2 is: combined with the power directivity diagram of the phased array wide beam antenna, the calculation formula is: Where Ta(x,y) is the antenna noise temperature function, T B (ξ,ζ) is the brightness temperature of the sun; A is the power directivity diagram of the phased array wide beam antenna; e is the effective area of ​​the antenna. And the process of calculating threshold 3 is: combined with the power directivity diagram of the phased array narrow beam antenna, the calculation formula is: Where Ta(x,y) is the antenna noise temperature function, T B (ξ,ζ) is the brightness temperature of the sun; A is the power directivity diagram of the phased array narrow beam antenna; e is the effective area of ​​the antenna;

[0038] Further, in the present invention, a narrow beam is used to perform a spatial search on the wave position searched in step S2, and the process is illustrated as follows: an initial (azimuth, elevation) angle is set according to the wave position, and the satellite service computer corrects the pitch angle as the starting pitch plane adjustment point; a small-angle scan in azimuth is performed in the wave position; it is determined whether the antenna noise temperature increases; when the antenna noise temperature increases, the azimuth / pitch maintains the current position, and a step search is performed nearby; when the antenna noise temperature does not increase, it is determined whether the azimuth has completed the wave position scan; when the azimuth has completed the wave position scan, a small-angle scan in pitch is performed; it is determined whether the pitch has completed the wave position scan; when the pitch has not completed the wave position scan, it is returned to the small-angle scan in azimuth in the wave position; when the pitch has completed the wave position scan, it indicates that the pointing is lost, and the process returns to step S2.

[0039] The following provides specific embodiments of the present invention.

[0040] Example 1

[0041] A method for forming a beam by a satellite phased array antenna to provide sun pointing in orbit comprises the following steps:

[0042] Step S1: Fixed wide-angle reception, reuse a single array in the broadband phased array, perform background noise measurement and analysis, combine the solar flux in the frequency band and its rate of change over time, when the antenna noise temperature of the single receiving array reaches the set threshold 1, determine that the single receiving array is pointing to the sun. Here, the satellite attitude sensor is required to determine the pointing position of the phased array, combined with the characteristics of the solar broadband noise, eliminate the co-frequency interference source; at this time, the phased array can perform the communication load function normally;

[0043] Step S2: Phased array wide beam coarse scanning. To obtain more accurate sun pointing, use part of the phased array to form a wide beam. Set the beam width and beam position according to the scanning time requirements (see the attached manual). Figure 2As shown), scan according to the wave position setting, combine the solar flux in the frequency band and its rate of change over time, and when the antenna noise temperature in the wide beam reaches the set threshold 2, determine that the wide beam direction points to the sun. Here, the satellite attitude sensor needs to be used to determine the pointing position of the phased array, and combine the characteristics of the solar broadband noise to eliminate the same-frequency interference source;

[0044] Step S3: phased array narrow beam fine scanning, using one beam in the phased array, setting a beam width comparable to that of the sun sensor, and performing a spatial search at the wave position searched in step S2;

[0045] Step S4: When the antenna noise temperature reaches the set threshold 3 during the phased array narrow beam fine scanning, it is determined that the narrow beam points to the sun, and the solar pointing data is provided to the satellite service computer. Since the sun is a non-point source, when the method of the present invention is used to provide solar pointing, the setting of the beam width of the narrow beam will have a certain impact on the result, specifically, the wider the beam width, the better the solar pointing performance.

[0046] Step S5: After determining that the narrow beam is pointing to the sun, the phased array narrow beam jitter tracking technology is used to continuously provide sun pointing information to provide perception capability for the satellite's in-orbit attitude.

[0047] In this embodiment, the threshold 1 set in step S1 is calculated in combination with the power directivity diagram of a single phased array antenna, and the calculation formula is: Where T B (ξ,ζ) is the brightness temperature of the sun; A is the power directivity diagram of a single-element phased array antenna; e is the effective area of ​​the antenna;

[0048] Calculate the array factor of the phased array wide beam in step S2 The calculation formula is:

[0049] in is the array factor of the planar array, M and N are the total number of antenna radiating units in the X-axis and Y-axis directions of the phased array, and the distance between the unit and the adjacent unit at any position (m, n) in the XY plane is d x and d y , the unit excitation is represented by a mn ;

[0050] Calculate the array factor of the phased array narrow beam in step S3 The calculation formula is:

[0051] in is the array factor of the planar array, M and N are the total number of antenna radiating units in the X-axis and Y-axis directions of the phased array, and the distance between the unit and the adjacent unit at any position (m, n) in the XY plane is d x and d y , the unit excitation is represented by a mn ;

[0052] In the calculation step S2, the threshold 2 is set in combination with the phased array wide beam antenna power directivity diagram, and the calculation formula is: Where Ta(x,y) is the antenna noise temperature function, T B (ξ,ζ) is the brightness temperature of the sun; A is the power directivity diagram of the phased array wide beam antenna; e is the effective area of ​​the antenna;

[0053] Use the narrow beam to perform spatial search on the wave position searched in step S2, and the process is illustrated as follows: set the initial (azimuth, elevation) angle according to the wave position, and the satellite service computer corrects the elevation angle as the starting elevation adjustment point; perform azimuth small-angle scanning in the wave position; determine whether the antenna noise temperature increases; when the antenna noise temperature increases, the azimuth / elevation maintains the current position and performs step search nearby; when the antenna noise temperature does not increase, determine whether the azimuth has scanned the wave position; when the azimuth has scanned the wave position, perform elevation small-angle scanning; determine whether the elevation has scanned the wave position; when the elevation has not scanned the wave position, return to performing azimuth small-angle scanning in the wave position; when the elevation has scanned the wave position, it indicates that the pointing is lost, and return to step S2;

[0054] In the calculation step S4, the threshold 3 is set in combination with the power directivity diagram of the phased array narrow beam antenna, and the calculation formula is: Where Ta(x,y) is the antenna noise temperature function, T B (ξ,ζ) is the brightness temperature of the sun; A is the power directivity diagram of the phased array narrow beam antenna; e is the effective area of ​​the antenna;

[0055] The present invention is based on the existing broadband communication payload phased array antenna, and achieves a receiving beam range accuracy comparable to that of a solar sensor through beam forming and a method of detecting solar noise, so as to enable the satellite phased array antenna to form a beam and provide solar pointing in orbit.

[0056] The technical principle of the present invention is described above in combination with the specific embodiments, which are only preferred implementations of the present invention. The protection scope of the present invention is not limited to the above embodiments, and all technical solutions under the idea of ​​the present invention belong to the protection scope of the present invention. Those skilled in the art can think of other specific implementations of the present invention without creative work, and these methods will fall within the protection scope of the present invention.

Claims

1. A method for forming a beam with a satellite phased array antenna to provide sun pointing in orbit, characterized in that: The following steps are involved: Step S1: Fixed wide-angle reception, when the antenna noise temperature of a single array in the multiplexed broadband phased array reaches a set threshold 1, it is determined that the single array is pointing to the sun; Step S2: phased array wide beam coarse scanning, using part of the array in the phased array to form a wide beam, when the antenna noise temperature in the wide beam reaches the set threshold 2, it is determined that the wide beam is pointing to the sun; Step S3: phased array narrow beam fine scanning, using the beam in the phased array to perform a spatial search at the wave position pointing to the sun in the phased array wide beam coarse scanning; Step S4: when the antenna noise temperature in the narrow beam of the phased array narrow beam fine scanning reaches the set threshold 3, it is determined that the narrow beam is pointing to the sun, and the sun pointing data is provided to the satellite service computer; Step S5: After determining that the narrow beam is pointing to the sun, the phased array narrow beam jitter tracking technology is used to continuously provide sun pointing information to provide perception capability for the satellite's in-orbit attitude.

2. A method for forming a beam by a satellite phased array antenna to provide sun pointing in orbit as claimed in claim 1, characterized in that: In step S1, the calculation process of threshold 1 is: Where Ta(x,y) is the antenna noise temperature function, is the brightness temperature of the sun; A is the power directivity diagram of a single-element phased array antenna; e is the effective area of ​​the antenna.

3. The method for forming a beam by a satellite phased array antenna to provide sun pointing in orbit as claimed in claim 1, characterized in that: In step S2, the calculation process of threshold 2 is: Where Ta(x,y) is the antenna noise temperature function, is the brightness temperature of the sun; A is the power directivity diagram of the phased array wide beam antenna; e is the effective area of ​​the antenna.

4. A method for forming a beam by a satellite phased array antenna to provide sun pointing in orbit as claimed in claim 3, characterized in that: The specific search process of step S3 is as follows: according to the initial angle set in the wave position, the satellite service computer corrects the pitch angle as the starting pitch adjustment point; performs a small-angle scan in azimuth in the wave position; determines whether the antenna noise temperature increases; when the antenna noise temperature increases, the azimuth / pitch maintains the current position and performs a step search nearby; when the antenna noise temperature does not increase, determines whether the azimuth has completed the wave position scan; when the azimuth has completed the wave position scan, performs a small-angle scan in pitch; determines whether the pitch has completed the wave position scan; when the pitch has not completed the wave position scan, returns to performing a small-angle scan in azimuth in the wave position; when the pitch has completed the wave position scan, it indicates that the pointing is lost, and returns to step S2 for a coarse scan again.

5. The method for forming a beam by a satellite phased array antenna to provide sun pointing in orbit as claimed in claim 1, characterized in that: The calculation process of the threshold 3 is: Where Ta(x,y) is the antenna noise temperature function, is the brightness temperature of the sun; A is the power directivity diagram of the phased array narrow beam antenna; e is the effective area of ​​the antenna.

6. The method for forming a beam by a satellite phased array antenna to provide sun pointing in orbit as claimed in claim 1, characterized in that: Specifically, step S1 includes multiplexing a single array in a broadband phased array to perform background noise measurement and analysis. By combining the solar flux in the frequency band and its rate of change over time, when the antenna noise temperature of the single array reaches a set threshold 1, it is determined that the single array is pointing to the sun.

7. The method for forming a beam by a satellite phased array antenna to provide sun pointing in orbit as claimed in claim 1, characterized in that: Specifically, step S2 uses part of the arrays in the phased array to form a wide beam, sets the beam width and the wave position according to the scanning time requirement, performs scanning according to the wave position setting, and combines the solar flux in the frequency band and its rate of change over time. When the antenna noise temperature in the wide beam reaches the set threshold 2, it is determined that the wide beam is pointing to the sun.

8. The method for forming a beam by a satellite phased array antenna to provide sun pointing in orbit as claimed in claim 1, characterized in that: The calculation process of the array factor of the phased array wide beam is as follows: in is the array factor of the planar array, M and N are the total number of antenna radiating units in the X-axis and Y-axis directions of the phased array, and the distance between the unit and the adjacent unit at any position (m, n) in the XY plane is d x and d y , the unit excitation is represented by a mn .

9. The method for forming a beam by a satellite phased array antenna to provide sun pointing in orbit as claimed in claim 1, characterized in that: The calculation process of the array factor of the phased array narrow beam is as follows: Among them, F is the array factor of the planar array, M and N are the total number of antenna radiating units in the X-axis and Y-axis directions of the phased array, and the distance between the unit and the adjacent unit at any position (m, n) in the XY plane is d x and d y , the unit excitation is represented by a mn .

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