Phased-array antenna for communication in motion and scanning method thereof

Abstract

The antenna comprises a main controller, an azimuth turntable and a phased-array antenna body, the phased-array antenna body is formed by regularly arranging and combining a plurality of sub-arrays, a pitching sub-turntable is correspondingly arranged below each sub-array, the pitching sub-turntables are arranged on the plane of the azimuth turntable, and the azimuth turntable is arranged on the plane of the azimuth turntable. And the pitch angle of each sub-array is controlled by the pitch sub-turntable below the sub-array. According to the invention, the pitching sub-turntable and the azimuth turntable cooperate with each other to complete two-dimensional scanning, and cooperate with the phased array surface to realize communication in motion; the sub-arrays can be spliced into a whole array, multi-sub-array partition scanning can also be carried out, scanning coverage of the whole airspace can be achieved only by controlling the orientation of the pitching sub-rotary table and the orientation rotary table without a phase shifter, the profile height and power consumption are reduced, and the cost is lower.

Description

Technical Field

[0001] The invention belongs to the field of antenna structures, and in particular relates to a phased array antenna for communication in motion and a scanning method thereof. Background Art

[0002] Traditional mobile communications use a parabolic antenna with a simple structure and a three-axis servo motor for mechanical scanning and star tracking; however, the parabolic antenna has a low operating frequency band, is large in size, and has low tracking accuracy for pure mechanical scanning. In the prior art, in order to overcome the shortcomings of traditional mobile communications tracking methods, phased array electronic scanning is used to achieve antenna tracking. Phased array antennas have the characteristics of miniaturization, low profile, and high performance (fast scanning speed and high accuracy), but the beam scanning range of phased array antennas is limited, and the scanning drop at large angles is large, so all-round antenna tracking cannot be achieved; and the cost of phased array antennas is limited by multi-functional chips and the price is relatively high. Summary of the invention

[0003] In view of this, in order to solve the above-mentioned deficiencies of the prior art, the object of the present invention is to provide a phased array antenna for communication in motion and a scanning method thereof, so that large-angle scanning has lower scanning drop and lower power consumption than a planar array, and further reduces costs.

[0004] To achieve the above purpose, the technical solution adopted by the present invention is: A hybrid electromechanical phased array antenna for communication in motion comprises a main controller, an azimuth turntable and a phased array antenna, wherein the phased array antenna is composed of a plurality of sub-arrays, each of which is provided with a corresponding elevation sub-turntable below, the elevation angle of the sub-array being controlled by the elevation sub-turntable below the sub-array, the elevation sub-turntable being arranged on the plane of the azimuth turntable, and the elevation angles of the plurality of elevation sub-turntables being synchronized.

[0005] Furthermore, when the pitch angle of the pitch sub-turntable is 0, the distance between two adjacent sub-arrays is zero, and all sub-arrays are spliced ​​into a complete array.

[0006] Furthermore, when the pitch angle of the pitch sub-turntable is not 0, the main controller performs power-off processing on an area where a sub-array is blocked by another adjacent sub-array.

[0007] Furthermore, the pitch angle is greater than or equal to 0° and less than or equal to 60°.

[0008] Furthermore, it also includes a servo motor, which is connected to the main controller and controlled by the main controller, and the rotation angles of all the pitch sub-turntables are synchronously controlled by the servo motor.

[0009] Furthermore, when the phased array antenna is scanning, the array elements in each sub-array are constructed into an equiphase plane by phasing, so as to realize the sub-array synthetic beams on different planes.

[0010] A scanning method of an electromechanical hybrid phased array antenna for communication in motion, comprising the following steps: Step 1: Use the satellite positioning system to determine the longitude and latitude of the current product, and use the high-precision inertial navigation system to determine the heading, pitch and roll attitude information of the current moving carrier; Step 2: Calculate the current position of the moving antenna beam in real time through the satellite tracking algorithm; Step 3: The control system first controls the azimuth turntable and the pitch turntable to point to the corresponding angles. Step 4: If the pointing angle exceeds the adaptable range of the turntable, control the phased array antenna to scan until it points to the target satellite.

[0011] The beneficial effects of the present invention are: 1. The pitch sub-turntable and the azimuth turntable of the present invention cooperate with each other to complete two-dimensional scanning, and cooperate with the electronic scanning of the phased array array itself to achieve moving communication. The phased array is decomposed into multiple molecular arrays by the pitch sub-turntable, which can greatly reduce the cross-sectional size; further, with the cooperation of the pitch azimuth turntable, the phase shifter in the phased array antenna can be completely discarded, and only the cooperation of the switch and the turntable is required to complete the scanning coverage of the entire airspace, which can greatly reduce the design cost of the phased array antenna; 2. When electronic scanning is needed to improve the scanning speed and accuracy of the system, the phased array antenna only needs to have a one-dimensional scanning capability to complete the airspace coverage, which can greatly save TR channels and the cost of multi-function chips by a one-drive-many approach; further, the maximum rotation angle of the turntable in the present invention is 60°. On this basis, the phased array antenna completes a total scanning range of 80° by electronic scanning of 20°, thereby completing the scanning of the pitch angle of 0-80°, and completing the azimuth scanning of 0-360° by controlling the azimuth turntable; 3. When the elevation sub-rotor is not started, the sub-arrays can be completely assembled into a whole array, and can be normally synthesized to complete small-angle scanning. At this time, the whole array works simultaneously; when the elevation sub-rotor is started, through special phase matching, the phased array sub-arrays on different planes can be normally synthesized beams and scanned; 4. When a sub-array unit is blocked, shutting down the blocked elements can further save power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0013] Figure 1 is a schematic diagram of the entire machine in a plane unfolded state when the pitch sub-turntable is not started in Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the whole machine scanning 60° when there are 5 pitch sub-turntables in Example 1 of the present invention; Figure 3 is a schematic structural diagram of the isophase surface when the subarray scans the normal direction in Embodiment 1 of the present invention; Figure 4 is a schematic structural diagram of the equiphase surface when the subarray scans the angle θ in Embodiment 1 of the present invention; Figure 5 It is the directional pattern after the sub-arrays are synthesized in different planes in Embodiment 1 of the present invention; The reference numerals are as follows: 1. phased array antenna, 2. elevation sub-turntable, 3. azimuth turntable. DETAILED DESCRIPTION

[0014] The following specific examples are given to further clearly, completely and in detail illustrate the technical solution of the present invention. This example is the best example based on the technical solution of the present invention, but the protection scope of the present invention is not limited to the following examples.

[0015] Example 1 A phased array antenna 1 for communication in motion, comprising a main controller, an azimuth turntable 3 and a phased array antenna 1, wherein the phased array antenna 1 is composed of a plurality of regularly arranged sub-arrays, a corresponding elevation sub-turntable 2 is provided below each of the sub-arrays, the elevation angle of each sub-array is controlled by the elevation sub-turntable 2 below the sub-array, the elevation sub-turntable 2 is arranged on the plane of the azimuth turntable 3, and the elevation angles of the plurality of elevation sub-turntables 2 are synchronized; It also includes a servo motor, which is connected to the main controller and controlled by the main controller. The rotation angles of all the pitch sub-turntables 2 are synchronously controlled by the servo motor.

[0016] For a large-size antenna with purely mechanical scanning, the antenna can be decomposed into multiple molecular arrays in one dimension by the pitch sub-turntable 2. The more sub-arrays are decomposed, the more the cross-sectional size can be reduced.

[0017] Furthermore, when the pitch angle of the pitch sub-turntable 2 is 0, the distance between two adjacent sub-arrays is zero, all sub-arrays are spliced ​​into a whole array, and the boundary of the phased array antenna is rectangular, achieving the same array aperture efficiency as a conventional full array; when the pitch angle of the pitch sub-turntable 2 is not 0, and the main controller cuts off the power to the area where the sub-array is blocked by another adjacent sub-array.

[0018] As an option, in this embodiment, the number of sub-arrays is 5, as shown in FIG. Figure 2 As shown, for a phased array antenna 1 with a diameter of 0.56 m, if it is decomposed into 5 sub-arrays when scanning 60°, the profile height can be reduced by 80% compared with the antenna that only continues to scan. Table 1

[0019] It is obvious from the table above that for traditional pure mechanical scanning, this method has a lower profile and less power consumption. For pure electrical scanning, this method has lower cost, lower scanning drop and lower power consumption.

[0020] The larger the inclination angle of the pitch sub-turntable 2, the larger the blocked part of the subsequent molecular array will be. The blocked part does not contribute to the scanning. For example, when the pitch sub-turntable 2 is tilted at 60°, 50% of the units in the subsequent molecular array will be blocked. At this time, this part of the array elements can be turned off to save power. Compared with the 4-5dB drop when the planar electronic scanning phased array scans to 60°, this electromechanical hybrid scanning only loses the gain of the 50% array elements that are turned off and 3dB when scanning 60°, and the power consumption is reduced by 50%.

[0021] Furthermore, communication in motion usually requires a scanning range of 60° or even more than 70° in the pitch plane and 0-360° in azimuth. Therefore, in order to meet the needs of communication in motion, in this implementation, the pitch angle is greater than or equal to an angle greater than 0° and less than or equal to 60°, and the pitch sub-turntable is controlled to achieve a -60°-60° scanning adjustment of the sub-array pitch angle. On this basis, the phased array antenna completes a total scanning range coverage of 80° through 20° electronic scanning; the azimuth turntable is controlled to achieve 360-degree azimuth adjustment of the sub-array, so the pitch sub-turntable and the azimuth turntable can cooperate with each other to complete two-dimensional scanning, and then cooperate with the electronic scanning of the phased array surface itself to achieve communication in motion.

[0022] Furthermore, when the phased array antenna 1 is scanning, the array elements in each subarray are built into an equiphase plane by phasing to realize the subarray synthetic beams on different planes. For the phased array antenna 1 divided into subarrays, since the centers of the subarrays are not in the same plane, according to the basic scanning principle of the phased array, to realize scanning, all the array elements need to be built into an equiphase plane by phasing. Figure 3 ,4 The two scanning conditions of the molecular array shown are the equal phase surface conditions when scanning the normal direction and scanning the angle θ. The array elements in the molecular array must meet the equal phase surface conditions to complete the scanning and ensure the maximum scanning gain.

[0023] Furthermore, in the present invention, through the cooperation of the pitch-azimuth turntable 3, the phase shifter in the phased array antenna 1 can be discarded, and only the cooperation of the switch and the turntable is required to complete the scanning coverage of the entire airspace, which can greatly reduce the design cost of the phased array antenna 1. If it is also necessary to cooperate with electronic scanning to improve the scanning speed and accuracy of the system, a 1-drive-many design can be made in the phased array antenna 1, with one TR channel driving multiple units; this is because the phased array antenna 1 only needs to have a one-dimensional scanning capability to complete airspace coverage, so the 1-drive-many method can greatly save TR channels and save the cost of multi-function chips.

[0024] Example 2 This embodiment provides a scanning method for a phased array antenna 1 for communication in motion, which can be applied to the phased array antenna 1 mentioned in the above embodiment, and adopts a method of adding inertial navigation and using program guidance tracking, including the following steps: Step 1: Use the satellite positioning system to determine the longitude and latitude of the current product, and use the high-precision inertial navigation system to determine the heading, pitch and roll of the current moving carrier; Step 2: Calculate the position of the current moving antenna beam in real time through the satellite tracking algorithm; Step 3: The control system controls the azimuth turntable 3 and the elevation turntable 2 to point to corresponding angles according to the data in step 2; Step 4: If the pointing angle exceeds the adaptation range of the azimuth turntable 3 and the elevation turntable 2, the phased array antenna 1 is controlled to scan until it points to the target satellite. Furthermore, in order to determine the scanning direction during tracking in motion, two key pieces of information are required: one is the position of the product (i.e. the satellite), which is directly informed by the ephemeris; the other is the position and attitude of the product system. The attitude of the product is obtained by high-precision inertial navigation, and the specific information is the heading, pitch, roll, longitude and latitude of the current moving carrier (i.e. the product system); the specific direction of the product is calculated through an algorithm to complete tracking.

[0025] Example 3 The difference from the above-mentioned embodiment 2 is that, in this embodiment, considering that the inertial navigation starts slowly, a conical scanning method is selected. In the initial stage of tracking, when the satellite and inertial navigation data are not obtained, conical scanning tracking is adopted to control the servo motor to perform full airspace coverage scanning according to the 3dB beam width of the antenna array, and then closed tracking is performed after the target satellite is captured. In summary, the present invention provides a phased array antenna for communication in motion and a scanning method thereof. With the cooperation of a pitch-azimuth turntable, the phase shifter can be discarded, and only the cooperation of a switch and a turntable is required to complete the scanning coverage of the entire airspace, which has lower scanning drop and lower power consumption and greatly reduces the design cost of the phased array antenna; the phased array antenna is composed of a plurality of sub-arrays, and the sub-arrays can be spliced ​​into a whole array to complete small-angle scanning.

[0026] The above shows and describes the main features, basic principles and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements according to actual conditions, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A phased array antenna for communication in motion, comprising a main controller, an azimuth turntable and a phased array antenna, characterized in that: The phased array antenna is composed of a plurality of sub-arrays, and a pitch sub-turntable is provided under each sub-array. The pitch angle of the sub-array is controlled by the pitch sub-turntable under the sub-array. The pitch sub-turntable is arranged on the plane of the azimuth turntable, and the elevation angles of the plurality of pitch sub-turntables are synchronized.

2. A phased array antenna for communication in motion according to claim 1, characterized in that: When the pitch angle of the pitch sub-turntable is 0, the distance between two adjacent sub-arrays is zero, and all sub-arrays are spliced ​​into a complete array.

3. The phased array antenna for communication in motion according to claim 1, characterized in that: When the pitch angle of the pitch sub-turntable is not 0, the main controller performs power-off processing on the area where the sub-array is blocked by another adjacent sub-array.

4. The phased array antenna for communication in motion according to claim 3, characterized in that: The pitch angle is greater than or equal to 0° and less than or equal to 60°.

5. The phased array antenna for communication in motion according to claim 1, characterized in that: It also includes a servo motor, which is connected to the main controller and controlled by the main controller. The rotation angles of all the pitch sub-turntables are synchronously controlled by the servo motor.

6. The phased array antenna for communication in motion according to claim 1, characterized in that: When the phased array antenna is scanning, the array elements in each sub-array are built into an equiphase plane by phasing, so as to realize the sub-array synthetic beams on different planes.

7. A scanning method for a phased array antenna for communication in motion, applied to the antenna set forth in any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1: Use the satellite positioning system to determine the longitude and latitude of the current product, and use the high-precision inertial navigation system to determine the heading, pitch and roll attitude information of the current moving carrier; Step 2: Calculate the current position of the moving antenna beam in real time through the satellite tracking algorithm; Step 3: The control system controls the azimuth turntable and the elevation turntable to point to corresponding angles according to the data in step 2; Step 4: If the pointing angle exceeds the adaptation range of the azimuth turntable and the elevation turntable, control the phased array antenna to scan until it points to the target satellite.

8. The scanning method of a phased array antenna for communication in motion according to claim 7, characterized in that: In step 3, the pitch sub-turntable and the phased array antenna are controlled to cooperate to complete the scanning of the pitch angle of 0-80°, and the azimuth turntable is controlled to complete the scanning of the azimuth angle of 0-360°.

9. The scanning method of a phased array antenna for communication in motion according to claim 7, characterized in that: When step 4 is performed electrically, 1 TR channel drives multiple units.

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