CN111710974B - Self-adaptive array element selection method suitable for multi-array element inclined plane array antenna - Google Patents
Self-adaptive array element selection method suitable for multi-array element inclined plane array antenna Download PDFInfo
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- CN111710974B CN111710974B CN202010601756.7A CN202010601756A CN111710974B CN 111710974 B CN111710974 B CN 111710974B CN 202010601756 A CN202010601756 A CN 202010601756A CN 111710974 B CN111710974 B CN 111710974B
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
- H01Q3/26—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture
- H01Q3/2605—Array of radiating elements provided with a feedback control over the element weights, e.g. adaptive arrays
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
- H01Q3/26—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture
- H01Q3/267—Phased-array testing or checking devices
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Abstract
The invention discloses a self-adaptive array element selection method suitable for a multi-array element inclined plane array antenna, which comprises the following steps: s1, generating a direction vector lookup table: s2, the method for forming beam pointing is as follows: receiving satellite direction angle values input from the outside, wherein the satellite direction angle values comprise a pitch angle and an azimuth angle; calling a lookup table according to the angle value to obtain a corresponding direction vector; weighting the direction vector and each channel input signal; a beam pointing signal is generated that is directed to the satellite. The invention aims at a digital phased array, utilizes a digital beam pointing technology to superpose the phases of a plurality of arrays in the digital field to generate a beam enhancement signal pointing to the direction of a satellite, can be widely applied to various multi-array element inclined plane array antennas and is used for realizing the beam pointing technology, such as a satellite navigation multi-array element antenna and a satellite communication multi-array element antenna.
Description
Technical Field
The invention relates to the field of satellite communication, in particular to a self-adaptive array element selection method suitable for a multi-array element inclined plane array antenna.
Background
In the field of satellite communication, in order to meet the application requirements of high gain, high sensitivity and reliable communication in motion, an antenna needs to be pointed to a satellite direction in real time, and a servo motor and a phased array mode are generally adopted. The servo motor is simple to realize and flexible to use, but the size is large and the requirement for miniaturization is difficult to meet. The phased array adopts a digital or analog beam pointing technology to form a beam enhancement signal with larger gain in a digital field. The phased array can be reduced in size through array arrangement design, beam pointing speed is high, and the phased array is suitable for more application occasions.
In some special application occasions, the sensitivity of a low elevation angle signal needs to be ensured, and due to the performance defect of the array at the low elevation angle, the general planar phased array cannot form accurate pointing and higher gain, so that the low elevation angle performance is deteriorated. In order to solve the problem of poor low elevation performance of the planar array, the size is increased, the number of the arrays is increased, and the planar array can be guaranteed in a slant array mode. Adopt the slashface array, can be in original array element area, change the planar array into the solid array, with the array according to certain angle tilt installation, with the array normal deviation zenith, utilize the array at the higher characteristics of normal gain, become high elevation through the array slope with original planar low elevation to promote low elevation performance.
To form accurate digital beam pointing, a direction vector needs to be generated through calibration, and then a corresponding beam pointing signal is generated according to the actual direction of the satellite.
The prior art has the disadvantage that all or only a few arrays are generally used to participate in beam pointing, and therefore the pointing gain and pointing accuracy for high and low elevation angles cannot be optimized. Because the design of the slope of array, must lead to partial array to face satellite signal, partial array receives the three-dimensional design of the slope of because array, must lead to partial array to face satellite signal, and partial array receives sheltering from of three-dimensional antenna self to satellite signal dorsad. At high elevation, if only a few arrays are adopted, the total gain of beam pointing is not as good as that of all the arrays, so that the sensitivity is reduced; at low elevation angles, if all the arrays are adopted, the beam pointing gain is not as good as that of only adopting a few arrays facing to the signal direction due to the influence of factors that the back array is blocked and the performance of the low elevation angle array is deteriorated, and the conditions of beam pointing inaccuracy and sensitivity reduction are also caused. The prior art is difficult to achieve the optimal sensitivity in high elevation angle and low elevation angle.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a self-adaptive array element selection method suitable for a multi-array element inclined plane array antenna.
The purpose of the invention is realized by the following technical scheme:
an adaptive array element selection method suitable for a multi-array element inclined plane array antenna comprises the following steps:
s1, generating a direction vector lookup table:
(1) placing an antenna in the center of a rotary table of a microwave darkroom;
(2) a far-field signal source is arranged to emit a calibration signal, and the pitching angle is adjustable from 0 degree to 90 degrees;
(3) the azimuth angle of the rotary table is adjustable from 0 degree to 360 degrees;
(4) setting a pitch angle and an azimuth angle, and transmitting a far-field signal;
(5) collecting data of each channel;
(6) calculating phase differences of all channels of the N array elements, obtaining direction vectors according to the phase differences, weighting the direction vectors with input signals of all the channels to generate beam pointing signals, and calculating the maximum power value G1 of the beam pointing signals;
(7) selecting channel combinations of different arrays facing to the direction of the satellite signal according to antenna parameters, calculating phase differences to obtain direction vectors under different combinations, weighting the direction vectors with input signals under various channel combinations to generate directional signals, and calculating power values G2-Gm under various different combined beam directional signals, wherein m is the number of adopted array elements, m is more than or equal to 1 and less than or equal to N, and N is the total number of antenna array elements;
(8) comparing the values of G1, G2, G3, … and Gm, and selecting a maximum value;
(9) writing the direction vectors of several arrays corresponding to the maximum value into a lookup table;
(10) the value of the unused array is zero;
(11) traversing all spatial angles according to a certain stepping value in the pitch angle and the azimuth angle;
(12) forming a final direction vector lookup table;
s2, the method for forming beam pointing is as follows:
(1) receiving satellite direction angle values input from the outside, wherein the satellite direction angle values comprise a pitch angle and an azimuth angle;
(2) calling a lookup table according to the angle value to obtain a corresponding direction vector;
(3) weighting the direction vector and each channel input signal;
(4) a beam pointing signal is generated that is directed to the satellite.
In substep (7) of step S1, the antenna parameters include array element number, array flow pattern, and tilt angle of the tilted array.
In the substep (7) of step S1, the number m of array elements may be set based on an empirical value.
And (7) selecting an array with an angle smaller than 90 degrees with the satellite signal to participate in combination in the substep of the step S1.
Compared with the prior art, the invention has the following advantages and beneficial effects:
the invention comprehensively considers the performance difference of high elevation and low elevation under different space angles, selects the optimal array combination, and improves the beam pointing accuracy and the pointing gain, thereby improving the signal sensitivity. Because the tilted array is a three-dimensional structure, part of the arrays are necessarily located on the back of the three-dimensional array, signals of the arrays are shielded by the antenna, the performance of the arrays under the condition of low elevation angle is poor, when the signals are incident from the low elevation angle, the arrays on the back can cause inaccurate beam pointing of final synthesis if participating in beam pointing weighting, and beam pointing gain is reduced. The invention does not limit the use of all or some arrays aiming at different pitch angles and direction angles, adopts the optimal array combination according to the performance difference expressed by different array combinations of the actual antenna under different space angles, optimizes the beam pointing accuracy and gain under various space angles, and ensures the application of the oblique plane array under various platforms and use environments.
Drawings
FIG. 1 is a diagram of an eight-element oblique array azimuth angle and an array element distribution diagram.
Fig. 2 is a flow chart of direction vector generation.
Fig. 3 is a flow chart of beam pointing signal generation.
Detailed Description
The present invention will be described in further detail with reference to examples and drawings, but the present invention is not limited thereto.
Referring to fig. 1, 2 and 3, a self-adaptive array element selection method suitable for a multi-array element inclined-plane array antenna selects different array combinations to participate in beam pointing according to different pitch angles and azimuth angles, and effectively improves beam pointing performance of an inclined-plane array. When a satellite signal is incident at a certain angle in space, the array facing the direction of the satellite signal only depends on the azimuth angle and is irrelevant to the pitch angle, so that only the azimuth angle can be considered for selecting the array, and the pitch angle is not considered. Meanwhile, under a high elevation angle, all the arrays participating in beam pointing can obtain better pointing accuracy and pointing gain than that of only selecting a few arrays, so that only the array selection condition under a low elevation angle is considered. An 8-element antenna is taken as an example (8 elements are taken as an example, and are not limited to 8 elements), as shown in fig. 1.
As shown in FIG. 1, 1-8 are antenna elements, the outermost number is azimuth angle, and the range is 0-360 deg. 8123, …, 7812, etc. in fig. 1, the numbers are numbers of selected four arrays (only three and four combinations are selected here for convenience of description, but it is not intended that only two combinations are used), and the triangular regions containing numbers indicate the angular range to be covered. 8 array evenly distributed, the contained angle is 45 between two antennas, the front is three or four towards the array that the satellite came to (supposing that selected array central point and signal incoming angle are less than 90 °), if satellite signal is regional the incidence at certain array central point, then adopt this array and respectively two arrays about and as the directional participation array of wave beam, if satellite signal is regional the incidence in the middle of certain two arrays, then adopt two arrays on these two arrays and the edge, totally four arrays are as the directional participation array of wave beam. As shown in fig. 1, the following is illustrated:
(1) satellite signals are incident near the 0-degree direction (non-triangular area), and three arrays 812 are adopted;
(2) satellite signals are incident near the 22.5 ° direction (triangular area), and 8123 four arrays are used.
The specific angle ranges (azimuth angles) of three or four arrays are adopted and can be set according to experience or actual test results. Taking 8 array elements as an example, as shown in fig. 1, assuming that the range angle of incidence of satellite signals using four arrays is 10 °, and the range angle of incidence of satellite signals using three arrays is 33 °, the azimuth range distribution and the corresponding array numbers used are shown in table 1.
TABLE 1 Azimuth Range and alignment Table
| Range of azimuth angles | Numbering of adopted arrays | Angular range |
| 344°～17° | 812 | 33° |
| 18°～28° | 8123 | 10° |
| 29°～62° | 123 | 33° |
| 63°～73° | 1234 | 10° |
| 74°～107° | 234 | 33° |
| 108°～118° | 2345 | 10° |
| 119°～152° | 345 | 33° |
| 153°～163° | 3456 | 10° |
| 164°～197° | 456 | 33° |
| 198°～208° | 4567 | 10° |
| 209°～242° | 567 | 33° |
| 243°～253° | 5678 | 10° |
| 254°～287° | 678 | 33° |
| 288°～298° | 6781 | 10° |
| 299°～332° | 781 | 33° |
| 333°～343° | 7812 | 10° |
In actual use, the combination of several arrays and the incidence angle range of satellite signals covered by different array combinations are determined according to the actual conditions of the antennas, and the mode and the angle range of the array combination are determined according to the actual test result of each antenna. Because the number of elements, the inclination angle, the out-of-roundness of the elements and other key parameters of different antennas are different, the scheme only gives reference values taking 8-element antennas as examples, and does not give clear values.
The method implementation flow chart of the present invention is shown in fig. 2 and fig. 3, and the following describes in detail the direction vector generation method and the beam forming pointing method by taking an 8-element antenna as an example.
The method for generating the direction vector comprises the following steps:
(1) placing an antenna in the center of a rotary table of a microwave darkroom;
(2) a far-field signal source is arranged to emit a calibration signal, and the pitching angle is adjustable from 0 degree to 90 degrees;
(3) the azimuth angle of the rotary table is adjustable from 0 degree to 360 degrees;
(4) setting a pitch angle and an azimuth angle, and transmitting a far-field signal;
(5) collecting data of each channel after phase consistency adjustment;
(6) calculating the phase difference of 8 channels, obtaining a direction vector according to the phase difference, weighting the direction vector with input signals of each channel to generate beam pointing signals, and calculating the maximum power value G1 of the beam pointing signals;
(7) calculating phase differences of 3 arrays facing the azimuth angle, obtaining direction vectors according to the phase differences, weighting the direction vectors with input signals of channels corresponding to the 3 arrays to generate beam pointing signals, and calculating a maximum power value G2 of the beam pointing signals;
(8) calculating phase differences of 4 arrays facing the azimuth angle, obtaining direction vectors according to the phase differences, weighting the direction vectors with input signals of channels corresponding to the 4 arrays to generate beam pointing signals, and calculating a maximum power value G3 of the beam pointing signals;
(9) calculating phase differences of N (N is more than or equal to 1 and less than or equal to 8) arrays facing the azimuth angle, obtaining direction vectors according to the phase differences, weighting the direction vectors with input signals of channels corresponding to the N arrays to generate beam pointing signals, and calculating the maximum power value GN of the beam pointing signals;
(10) comparing the values of G1, G2, G3, … and GN, and selecting the maximum value;
(11) writing the direction vectors of several arrays corresponding to the maximum value into a lookup table;
(12) the value of the unused array is zero;
(13) traversing all spatial angles according to a certain stepping value in the pitch angle and the azimuth angle;
(14) forming a final direction vector look-up table.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (7)
1. An adaptive array element selection method suitable for a multi-array element inclined plane array antenna is characterized by comprising the following steps:
s1, generating a direction vector lookup table;
s2, the method for forming beam pointing is as follows:
(1) receiving a direction angle value of an externally input satellite signal;
(2) calling a lookup table according to the angle value to obtain a corresponding direction vector;
(3) weighting the direction vector and each channel input signal;
(4) generating a beam pointing signal pointing to a satellite;
the step S1 specifically includes:
(1) placing an antenna in the center of a rotary table of a microwave darkroom;
(2) a far-field signal source is arranged to emit a calibration signal, and the pitching angle is adjustable from 0 degree to 90 degrees;
(3) the azimuth angle of the rotary table is adjustable from 0 degree to 360 degrees;
(4) setting a pitch angle and an azimuth angle, and transmitting a far-field signal;
(5) collecting data of each channel after the phase of each channel is adjusted in a consistent manner;
(6) calculating phase differences of all channels of the N array elements, obtaining direction vectors according to the phase differences, weighting the direction vectors with input signals of all the channels to generate beam pointing signals, and calculating the maximum power value G1 of the beam pointing signals;
(7) selecting channel combinations of different arrays facing to the far-field signal direction according to antenna parameters, calculating phase difference to obtain direction vectors under different combinations, weighting the direction vectors with input signals under various channel combinations to generate directional signals, and calculating power values G2-Gm under various different combined beam directional signals, wherein m is the number of adopted array elements, m is more than or equal to 1 and less than or equal to N, and N is the total number of antenna array elements;
(8) comparing the values of G1, G2, G3, … and Gm, and selecting a maximum value;
(9) writing the direction vectors of several arrays corresponding to the maximum value into a lookup table;
(10) the value of the unused array is zero;
(11) traversing all spatial angles according to a certain stepping value in the pitch angle and the azimuth angle;
(12) forming a final direction vector look-up table.
2. The adaptive array element selection method for the multi-array element tilted-plane array antenna according to claim 1, wherein in the substep (7) of step S1, the antenna parameters comprise the number of array elements, the array pattern and the tilted plane array angle.
3. The adaptive array element selection method for a multi-element diagonal array antenna according to claim 1, wherein in the substep (7) of step S1, the number m of the array elements can be set based on an empirical value.
4. The adaptive array element selection method for the multi-element diagonal array antenna according to claim 1, wherein in the substep (7) of step S1, an array element with an angle smaller than 90 ° with respect to the satellite signal is selected to participate in the combination.
5. The adaptive array element selection method for a multi-element diagonal array antenna according to claim 1, wherein in the substep (1) of step S2, the direction angle values comprise a pitch angle and an azimuth angle.
6. The adaptive array element selection method for the multi-element diagonal array antenna according to claim 5, wherein the azimuth angle is set according to experience or actual test results.
7. The adaptive array element selection method for the multi-array element diagonal array antenna according to claim 5, wherein the azimuth angle is set by an "azimuth angle range and element mapping table".
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