KR101095996B1 - Method of beam nulling in phase arrangement antenna - Google Patents
Method of beam nulling in phase arrangement antenna Download PDFInfo
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- KR101095996B1 KR101095996B1 KR20100034974A KR20100034974A KR101095996B1 KR 101095996 B1 KR101095996 B1 KR 101095996B1 KR 20100034974 A KR20100034974 A KR 20100034974A KR 20100034974 A KR20100034974 A KR 20100034974A KR 101095996 B1 KR101095996 B1 KR 101095996B1
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Abstract
The present invention relates to a phased array antenna beam nulling method of a coded crossover phase control method. In the case of the beamforming algorithm of a phased array antenna using a general genetic algorithm, a null is formed by controlling a phase value by crossing and shifting phase values represented by binary codes, so that the phase weight to be adjusted as the number of array elements increases. Will increase. The present invention is an algorithm designed to improve the degradation of the convergence speed and the disadvantage that the beam is not formed in real time, in order to adjust the phase of the phased array antenna in which a plurality of elements are arranged, the phase of all devices directly obtained Compared to the existing genetic algorithm, the phase values on the left and right sides of the array antenna are the same and the sign is changed in units of elements, so that the convergence speed can be greatly reduced in terms of algorithm. There is an advantage.
Description
The present invention relates to an adaptive beamforming antenna, and in particular, a null synthesis technique applied to an adaptive beamforming antenna for suppressing a jamming signal by forming a null on an antenna pattern in a jammer direction by using a spatial separation characteristic between a user signal and an interference signal. It is about.
The adaptive beamforming algorithm used to synthesize nulls in the direction in which the interference signal is incident in the adaptive beamforming antenna may be classified into various types according to information required to obtain a weight vector applied to each array element. Among them, the adaptive beamforming algorithm using the genetic algorithm belongs to the algorithm using the final output power, and the hardware can be easily implemented and can be implemented at low cost. On the other hand, the adaptive beamforming algorithm using the genetic algorithm has been studied a lot because of the above-mentioned advantages, but most of the techniques for the performance for the performance is limited to the theoretical aspects.
1 is a geometry of a phased array antenna used in an adaptive beamforming antenna. Referring to FIG. 1, a phased array antenna includes a linear
That is, as shown in Figure 1, the
In the case of the beamforming algorithm of a phased array antenna using a general genetic algorithm, a null is formed by controlling a phase value by crossing and shifting phase values represented by binary codes, so that the phase weight to be adjusted as the number of array elements increases. Will increase. In the prior art, in adjusting the phase of a phased array antenna in which a plurality of elements are arranged, since the phases of all the elements are directly obtained, a large amount of time is required for phase calculation.
In other words, when synthesizing nulls using a conventional genetic algorithm, since the array elements of the plurality of antennas used in the actual adaptive beamforming antennas are not assumed, the time required for null synthesis becomes very long, thus inevitably smooth. Difficult to maintain communication Due to the characteristics of the genetic algorithm, nulls are formed through the crossover and variation of the phase values represented by binary codes. As the number of array elements increases, the phase weight to be adjusted also increases, so that the amount of calculation increases exponentially. . Therefore, when the null formation using the genetic algorithm, the length of one candidate group increases in proportion to the total number of antennas, there is a disadvantage that the convergence due to hybridization and mutation is not smooth. For this reason, only a limited number of phased array antennas can implement the beamforming algorithm using the genetic algorithm.
On the other hand, Shore is designed to have the same phase value and different sign values applied to both symmetrical elements from the center of the antenna array to improve the performance of the adaptive beamforming algorithm using the genetic algorithm. It was. This technique improves performance, but as the number of array elements increases, the main beam moves in one direction.
An object of the present invention has been proposed to solve the above problems, and in adjusting the phase of the phased array antenna having a large number of arrays applicable to the actual adaptive beamforming antenna, a genetic algorithm that adjusted the phase applied to all existing antennas The time required to calculate the phase value is remarkably reduced by improving the shape of the antennas arranged in the right and left symmetrical with respect to the center of the array antenna.
It is also an object of the present invention to provide a beam nulling method of a phased array antenna of a coded crossover phase control method in which a main beam is not distorted from side to side due to continuous cross signing.
In order to solve the above problems, the present invention provides a method for forming a phased array antenna beam null according to the present invention.
A method of forming beam nulls based on a genetic algorithm in a phased array antenna system,
Determining that a blind signal is input when the received power increases rapidly with the phased array antenna;
And suppressing the jamming signal, applying a phase value by crossing a sign from the center of the array of the antenna to form a null pattern.
Preferably, the phase value is
The size of the phased array antenna is the same, so that the left and right symmetry, characterized in that the sign of the phase cross each other.
Preferably, the null pattern formation may be configured by changing the magnitude of the current.
Preferably, the size of the current applied to the antenna for minimizing the side lobe rise caused in the beam null formation is characterized in that it is limited to a certain form.
Preferably, the method may further include inputting data information necessary for forming a null pattern for suppressing the jamming signal.
Preferably, the necessary data is characterized by including the number of elements and the arrangement interval of the array antenna, the phase shift information (number of bits), and the shift probability value of the phase value.
In addition, the present invention to solve the above problems, the phased array antenna system according to the present invention,
A method of forming beam nulls based on a genetic algorithm in a phased array antenna system,
Determining that a blind signal is input when the reception power increases rapidly with the phased array antenna;
In order to suppress the jamming signal, a module for performing beam null formation based on a genetic algorithm performing phase control by applying a phase value by crossing a sign from the center of the antenna array to form a null pattern is included. It is done.
In addition, the present invention to solve the above problems, the method of forming a phased array antenna beam null according to the present invention
A method of forming beam nulls based on a genetic algorithm in a phased array antenna system,
Determining that a blind signal has entered when the received power increases rapidly with the phased array antenna, and inputting data information necessary for null implementation;
Generate a bit string equal to 1/2 of the number of the received antenna elements and the number of lower bits used in null synthesis, apply the generated bit string to a phase shifter as a phase value, and perform evolution through crosses. Generating an initial phase group by generating a plurality of bit strings so as to form a population in a matrix form;
Symmetrically applying a magnitude of a phase value of the generated phase population to the center of the antenna array;
The symmetrically applied phase values may be applied to have different codes, thereby performing code crossover phase control.
In the present invention, in adjusting the phase of a phased array antenna having a large number of arrays that can be applied to an actual adaptive beamforming antenna, the size of the array antenna is symmetrically based on the center of the array antenna in a genetic algorithm that has adjusted the phase applied to all the existing antennas. By improving the same and different codes applied to adjacent phase shifters, the time required for calculating the phase value can be significantly reduced.
In addition, the present invention has the effect that the main beam is not distorted left and right because the sign is continuously crossed.
FIG. 1 is a diagram illustrating a structure of a linear phased array antenna, in which an antenna, a variable amplifier, and a phase shifter are connected.
2 is a flowchart illustrating a null pattern implementation using a general genetic algorithm in a linear phased array antenna.
3 is a flowchart illustrating an embodiment of a genetic algorithm to which a code crossover phase concept is applied for implementing an optimal null pattern according to the present invention.
4 is a phase form in a null pattern implementation to which a general genetic algorithm is applied.
5 is a phase form of the algorithm proposed by Shore.
6 is a phase form in the algorithm of the present invention.
7 is a main beam distortion diagram of the beam pattern of the algorithm proposed by Shore.
FIG. 8 is a main beam distortion diagram of the beam pattern of the present invention for comparison with the beam pattern of the algorithm proposed by Shore of FIG.
9 is a null pattern for a single interference signal in the 1x100 antenna using the algorithm of the present invention.
10 is a nulling resolution (resolution) that can be implemented through the algorithm of the present invention.
11 is an array antenna structure diagram for analyzing the results of the present invention algorithm and commercial tools.
12 is an exemplary diagram of a phase value calculated through the algorithm of the present invention.
Figure 13 is an illustration of the radiation pattern between the algorithm of the present invention and a commercial tool.
The present invention is applied to a phased array antenna beam nulling method of a code crossover phase control method. However, the present invention is not limited thereto, and the technical idea of the present invention may be applied to systems and fields of other technical fields.
As the inventive concept allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.
Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. The term “and / or” includes any item of a plurality of related listed items or a plurality of related listed yields.
When an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may be present in between. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described on the specification, and one or more other features. It is to be understood that the present disclosure does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.
Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.
Briefly describing the concept of the present invention.
In the case of the beamforming algorithm of a phased array antenna using a general genetic algorithm, a null is formed by controlling a phase value by crossing and shifting phase values represented by binary codes, and thus, the phase weight to be adjusted as the number of array elements increases. It will also increase. This causes a problem of lowering convergence speed and not forming a beam in real time. The present invention proposes a method or algorithm that can improve such a problem, and in adjusting the phase of a phased array antenna in which a plurality of devices are arranged using the algorithm, the present invention is based on the existing genetic algorithms that directly obtain the phases of all devices. Compared to the center element of the array antenna, the phase values on the left and right sides are the same, and the sign is changed so that the sign is changed in units of elements.
Therefore, when using the present invention, there is an advantage of real-time beam formation by greatly reducing the convergence speed in terms of algorithms, and in the hardware side, only one receiver is used at the end using a genetic algorithm, so that other radar / smart antennas / satellites are used. The implementation cost of a receiver can be significantly reduced compared to an algorithm using a covariance matrix used in a mounting nulling antenna. In addition, the present invention has the advantage of enabling accurate beam steering by greatly reducing the left and right movement of the main beam according to the synthesis of the null pattern by applying the code cross-phase concept.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The description will be omitted.
2 is a flow diagram of an embodiment of a beamforming algorithm implementation based on a genetic algorithm.
Referring to FIG. 2, when a jamming signal is transmitted toward an adaptive beamforming antenna in a specific direction, since a communication signal and a jamming signal are simultaneously received through each individual element of the linear phased array antenna, suddenly compared with the conventionally received power. The reception power is suddenly increased (S200). At this time, the execution of the algorithm is started.
When the received power increases rapidly, the algorithm determines that a jamming signal is incident, and inputs data information necessary for forming a null pattern for suppressing the jamming signal (S210). In this case, the necessary data to be input includes element number / array spacing of the array antenna, phase shift information (number of bits), shift probability values of the phase value, and the like.
Subsequently, an arbitrary initial phase population is generated to generate phase values to be applied to the phase shifter (S220). That is, a bit string is generated by the product of the number of antenna elements input in the process S210 and the number of lower bits commonly used for null synthesis. Here, the bit string is a phase value applied to the phase shifter, and a plurality of bit strings are generated to form a population of the format behavior so that evolution through crosses is possible.
Received power is measured by applying the phase of each bit string of the population to each array element (S230). At this time, if the received power measured in the step (S230) is detected to be above a predetermined threshold value, the rearrangement process according to the received power value through the selection step of the genetic algorithm (S240). In the step S240, the bit strings are arranged in descending order according to the received power values of the bit strings, and the half bit strings are discarded in the order in which the received powers are larger. Data rearranged through the S240 undergoes a mating process, and generates as many bit strings as discarded numbers through the mating process so as to obtain a lower power (S250). Subsequently, the fitness is re-evaluated through the mutation execution process (S260) based on the input ratio so as not to fall into the local solution. That is, after performing the step S260, the reception power is measured by applying the phase of each bit command (S230). Thereafter, if the measured received power is less than or equal to the threshold value, the phase information of the bit string generating the received power less than or equal to the threshold value is applied to the phase shifter (S270), so that the received power is maintained to be less than or equal to the threshold value (S280).
FIG. 3 is a flowchart illustrating an optimal algorithm for implementing an adaptive beamforming antenna based on a genetic algorithm based on a code cross-phase concept according to the present invention. As compared with the case of FIG. 2, FIG. 3 is a step (S300) of applying a phase by applying the concept of a sign crossing phase according to the present invention in the case of FIG. 2. For the sake of brevity of the present description, the description of the same procedure as in FIG. 2 uses the corresponding description in FIG.
The present invention is a process for applying a phase value to which a sign intersection concept is applied after an initial phase group generation step, out of the conventional method of controlling the phases of all array elements by an adaptive beamforming algorithm based on a genetic algorithm. By generating (S300), the symbols applied to the adjacent phase shifters are the same in magnitude and symmetrically from the center of the array antenna.
4 is a phase form in null synthesis to which a general genetic algorithm is applied, so that phase values of all phase shifters are obtained through an algorithm.
FIG. 5 is a phase form of the algorithm proposed by Shore, and has the same magnitude and opposite sign from the center. When applying this type of phase, the performance speed can be improved, but as the number of array elements increases, the main beam moves in one direction.
FIG. 6 is a phase form in the algorithm of the present invention, whereas a general algorithm calculates and applies only all phase values through an algorithm so that only half of the phase values are obtained and applied to be symmetrical from the center of the array. On the other hand, the signs of adjacent phase values are applied to be different from each other. As a result, only half of the phase value is obtained, thereby significantly reducing the amount of calculation, and minimizing distortion in which the main beam moves to the left and right by having a different sign from the adjacent phase.
7 is a main beam distortion diagram of the beam pattern of the algorithm proposed by Shore.
FIG. 8 is a main beam distortion diagram of the beam pattern of the present invention for comparison with the beam pattern of the algorithm proposed by Shore of FIG.
The upper graph of FIG. 7 is a beam pattern when the conventional Shore proposed phase is applied, and distortion of the main beam is shifted to the left in the graph represented by the odd-sign phase (GA). However, as shown in FIG. 8, since the beam distortion does not occur in the GA (positive-sign phase) of the lower graph when the phase shape presented in the present invention is applied, the present invention has confirmed the advantage.
9 is a result of checking how a null pattern for a single interference signal is formed using the algorithm of the present invention. In FIG. 9, Reference represents a radiation pattern when a jamming signal is not applied to the genetic algorithm, and GA represents an antenna radiation pattern when the jamming signal is applied by applying a sign cross-phase concept to the genetic algorithm. In this case, it is assumed that the incident angle of the jamming signal is incident at θ = 1.7 °. Looking at Figure 8 it can be seen that about -70 dB of null is formed in the direction θ = 1.7 °.
FIG. 10 is a graph for verifying null synthesis resolution (resolution) that can be implemented through an algorithm of the present invention, in which nulls are formed when an interference signal is incident at θ = 2.8 ° and θ = 3 °. At this time, it was confirmed that the jamming signal suppression degree is about -75 dB. In addition, as a result of checking the nulling resolution, which is one of the most important performances of the nulling antenna, it can be seen that it implements a resolution of 0.2 °. In addition, it is confirmed that null formation is performed smoothly even when two jamming signals are incident.
11 is an array antenna structure diagram for comparison analysis with existing commercial tools to analyze null pattern accuracy when the algorithm of the present invention is applied. The linear phased array antenna structure used for the comparison of results was performed for the 1x20 type linear phased array antenna structure due to the limitation of computer specification. At this time, the antenna design specification used was designed with a center frequency of 7.825 GHz and a bandwidth of 14.7%, and the array spacing of the single radiating elements was arranged at half wavelength.
12 are phase values applied to a phase shifter to represent a null generated at θ = 8 ° calculated as a result of the present invention through a general commercial tool.
As can be seen in Figure 13, when comparing the synthesized null pattern by applying the present invention (MATLAB) and the general commercial tool (MWS) it was confirmed that forms a precise null in the θ = 8 ° direction. Through this, it was confirmed that the null synthesis accuracy of the present invention is very high.
Through the present invention described above, when the actual nulling antenna operation, the algorithm applied to the concept of the code crossover phase has a merit that can significantly reduce the time required to calculate the phase value because the number of phase values to be adjusted is greatly reduced, In addition, the main beam is not distorted from side to side because the signs are continuously crossed.
Therefore, in the case of using the present invention, the convergence speed is greatly reduced in terms of algorithm, and thus, the real-time beam is formed. In the hardware aspect, only one receiver can be implemented at the last stage to perform the same function. The implementation cost of the receiver can be drastically reduced compared to the algorithm using the covariance matrix used for the nulling antenna for satellite mounting. In addition, by applying the concept of code cross-phase, the main beam has a merit to precisely reduce the left and right movement of the main beam by synthesizing a null pattern.
The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and it is common in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be evident to those who have the knowledge of God.
Claims (8)
Determining that a jamming signal is input when the reception power increases rapidly with the phased array antenna;
And suppressing the jamming signal and applying a phase value by crossing a sign at the center of the array of the antenna to form a null pattern. 2.
The method of claim 9, wherein the phase array antenna beam null forming method has the same size and crosses the symbols of the phases so as to be symmetrical with respect to the center of the phased array antenna.
A method of forming a phased array antenna beam null, characterized in that it can be configured by changing the magnitude of the current.
A method of forming a phased array antenna beam null, characterized in that to limit the magnitude of the current applied to the antenna to minimize the side lobe rise phenomenon generated in the beam null formation.
A method of forming a phased array antenna beam null comprising the number of elements and array intervals of array antennas, phase shift information (number of bits), and the probability of shift of phase values.
In order to suppress the jamming signal, a module for performing beam null formation based on a genetic algorithm performing phase control by applying a phase value by crossing a sign from the center of the antenna array to form a null pattern is included. A phased array antenna system.
Determining that a jamming signal is incident when the reception power increases rapidly with the phased array antenna, and inputting data information necessary for null implementation;
Generate a bit string equal to 1/2 of the number of the received antenna elements and the number of lower bits used in null synthesis, apply the generated bit string to a phase shifter as a phase value, and perform evolution through crosses. Generating an initial phase group by generating a plurality of bit strings so as to form a population in a matrix form;
Symmetrically applying a magnitude of a phase value of the generated phase population to the center of the antenna array;
And applying the symmetrically applied phase values so as to have different codes, thereby performing sign-crossing phase control.
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| CN103064089A (en) * | 2012-12-28 | 2013-04-24 | 中国电子科技集团公司第五十四研究所 | Method for calibrating satellite navigation digital multi-beam launching array antenna phase center |
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| KR101432932B1 (en) * | 2013-04-15 | 2014-09-23 | 광운대학교 산학협력단 | Method and apparatus for estimating target in jammer scenario |
| KR101603630B1 (en) * | 2014-07-23 | 2016-03-15 | 국방과학연구소 | Method and Apparatus for suppressing jammer signals and estimating Angle Of Arrival of original signal using orthogonal of transmitting signal waveform |
| CN105187105B (en) * | 2015-08-05 | 2018-06-22 | 上海交通大学 | Improve the optimization method of null in intelligent antenna beam shaping using center antenna |
| KR101957290B1 (en) * | 2016-12-23 | 2019-06-27 | 국방과학연구소 | Cross-eye jamming system |
| KR102033749B1 (en) * | 2017-04-25 | 2019-10-17 | 국방과학연구소 | Method for performance improvement of array cross eye system |
| CN112864624B (en) * | 2020-12-30 | 2022-12-13 | 上海擎昆信息科技有限公司 | Method and device for adjusting and controlling received wave beam and terminal antenna system |
| CN117411497B (en) * | 2023-12-13 | 2024-02-13 | 中山大学 | Full duplex phased array and radio frequency decoupling network thereof |
| CN117805739B (en) * | 2024-02-27 | 2024-05-07 | 成都凌亚科技有限公司 | Wave control signal processing equipment and method |
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| CN103064089A (en) * | 2012-12-28 | 2013-04-24 | 中国电子科技集团公司第五十四研究所 | Method for calibrating satellite navigation digital multi-beam launching array antenna phase center |
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