Correction method for open-loop receiving phase matching directional diagram

Abstract

The invention belongs to the field of phased-array antennas, and relates to a correction method for an open-loop receiving phase-matching directional diagram, which comprises the following steps: controlling a corresponding radiation unit to work, and enabling other radiation units to be standby; sequentially acquiring amplitude control words and phase control words of all radiation units when the amplitude phases are consistent with the target value; performing software simulation in a non-cascade state to obtain a first scattering matrix and a second scattering matrix of all radiation units under the same phase matching frequency point; and finally, sequentially selecting one tested unit, obtaining an additional amplitude and an additional phase value according to the complex current, and subtracting the additional amplitude and the additional phase value to obtain a new amplitude control word and a new phase control word. And the influence of other radiation units on the unit to be tested can be quickly removed in a manner of polling additional complex current, so that a new amplitude control word and a new phase control word can be accurately and quickly obtained. And the correction can be completed without iteration, and the condition of iteration non-convergence does not occur.

Description

Technical Field

[0001] The present application belongs to the field of phased array antennas, and in particular to a method for correcting an open-loop receiving phase-matching pattern. Background Art

[0002] Since phased array antennas have flexible beam agility capabilities, radar systems in low interception mode require the antenna to have a lower sidelobe level.

[0003] The antenna low sidelobe is achieved by changing the amplitude and phase parameters of each element of the phased array antenna to change the antenna pattern shape so that it has lower sidelobes. The general method is to reduce the antenna sidelobe level through amplitude weighting, and the weighting method is generally Gaussian weighting or Taylor weighting.

[0004] There is a mutual coupling relationship between the radiating elements of the phased array antenna, and the standing waves at each port of the T / R component are different. Therefore, it is difficult to achieve the design target value of the sidelobe level by open-loop phase matching.

[0005] In order to achieve that the antenna sidelobe level is basically consistent with the design value, the three-dimensional radiation pattern of the antenna can be tested in the near field, and then the amplitude and phase data of each port of the antenna T / R component can be iteratively corrected through the aperture field back-modeling. However, this method is time-consuming and there may be a situation where the iteration does not converge.

[0006] Therefore, how to achieve fast and stable correction of the open-loop receiving phase matching pattern is a problem that needs to be solved. Summary of the invention

[0007] The purpose of the present application is to provide a method for correcting an open-loop receiving phase matching pattern, so as to solve the problem that the existing method for correcting an open-loop receiving phase matching pattern is time-consuming.

[0008] The technical solution of the present application is: a method for correcting an open-loop receiving phase matching pattern, comprising:

[0009] Build a phase matching environment, control the probe to move to the front of each radiating unit in turn, control the corresponding radiating unit to work and other radiating units to standby; when the amplitude and phase are consistent with the target value, obtain the amplitude control word and phase control word of all radiating units in turn;

[0010] Perform software simulation without cascading to obtain the first scattering matrix S1 of all radiating units at the same phase matching frequency point; then cascade each radiating unit and calculate the second scattering matrix S of all radiating units according to the reflection coefficient of each cascade channel. new ;

[0011] The second reflection coefficients of all radiation units are calculated according to the second scattering matrix of all radiation units, and a unit to be measured is selected in turn, and the complex current I added to the unit to be measured by other radiation units is calculated according to the reflection coefficient.n , obtain additional amplitude and additional phase values ​​according to the complex current, and subtract the additional amplitude and additional phase values ​​from the amplitude control word and the phase control word to obtain new amplitude control word and phase control word.

[0012] Preferably, the first scattering matrix S1 is obtained by:

[0013] Select a simulation software to model the real environment of the antenna array. By setting the same operating frequency point for the radiating elements, simulate and test the array composed of the radiating elements to obtain the first scattering matrix of all radiating elements at the same matching frequency point.

[0014] Preferably, the second scattering matrix S new The method to obtain is:

[0015] Convert the first scattering matrix into a first impedance matrix Z1;

[0016] Test the first reflection coefficient S of the T / R component channel corresponding to M radiation units tr ;

[0017] According to the first reflection coefficient S of the T / R component channel tr Calculate the port impedance Z of each T / R component channel in standby state tr ;

[0018] Pair port impedance Z tr Normalize and get the diagonal matrix Z tr1 ;

[0019] According to the diagonal matrix Z tr1 The impedance matrix Z1 is used to calculate the second impedance matrix Z after the radiator is cascaded with T / R components. new ;

[0020] According to the impedance matrix Z new Calculate the second scattering matrix S after the radiation unit cascades the T / R components new .

[0021] Preferably, the calculation formula of the first impedance matrix Z1 is: Z1 = (U + S1) * (U - S1) -1 , where U is the M×M unit matrix and M is the number of radiation units;

[0022] The port impedance Z tr The calculation formula is: tr =(1+S tr ). / (1-S tr ), Z tr is an M×1 complex matrix;

[0023] The diagonal matrix Ztr1 The calculation formula is: tr1 (n, n) = suqr(Z tr (n)), the value range of n is 1 to M;

[0024] The second impedance matrix Z new The calculation formula is: new =Z tr1 -1 *Z1*Z tr1 -1 *50;

[0025] The second scattering matrix S new The method to obtain S is: new =(Z new +U) -1 *(Z new -U).

[0026] Preferably, the method for obtaining the second reflection coefficient ss is:

[0027] Move the probe to the front of the nth radiation unit. The distance from the probe to the nth radiation unit is d, and the value range of n is 1 to M.

[0028] Calculate the distance d1 from the transmitting probe to the M radiation units, where d1 is an M×1 matrix;

[0029] Calculate the first phase value from the transmitting probe to each radiating unit according to the distance d1 in is an M×1 matrix;

[0030] According to the first phase value of each radiating unit Calculate the second reflection coefficient ss of the M radiation elements, ss is an M×1 matrix, where ss(n)=S new (n, n).

[0031] Preferably, the complex current I added by the other radiating units to the unit under test n The specific calculation method is:

[0032] The second scattering matrix S of all radiation units new Remove the row number of the unit under test and get the third scattering matrix S new1 ;

[0033] The first phase value from the transmitting probe to each radiating element Subtract the row number of the unit under test from the value to get the second phase value

[0034] Calculate the third reflection coefficient ss1 of the units except the nth radiation unit;

[0035] Calculate the complex current I added to the radiation element n in addition to other radiation elements n .

[0036] Preferably, the third scattering matrix S is calculated in matlab new1 The formula is:

[0037] S new1 =S new

[0038] S new1 (n,:) = []

[0039] Among them, [] means removing all columns of the nth row;

[0040] Calculate the second phase value in matlab The formula is:

[0041]

[0042] The formula for calculating the third reflection coefficient ss1 in Matlab is:

[0043] ss1=ss

[0044] ss 1 (n) = [].

[0045] Preferably, the calculation formula of the additional amplitude and the additional phase value is:

[0046] In the formula, abs is the absolute value calculation, and angle is the angle calculation.

[0047] Preferably, the specific method of sequentially acquiring the amplitude control words and the phase control words of all the radiation units is:

[0048] Configure the power supply, PC host, vector network analyzer, active phased array antenna and movable probe in sequence, build the matching environment, and connect the instruments;

[0049] The movable probe is controlled by the PC host to move to the front of the first radiation unit;

[0050] The receiving work of the first radiation unit of the T / R component is controlled by the PC host, and other T / R channels are in the receiving standby state;

[0051] Collect amplitude and phase data of vector network analyzer through PC host;

[0052] The amplitude and phase of the first T / R component are controlled by the PC host to be consistent with the target value;

[0053] The movable probe is controlled by the PC host to move to the next radiation unit and collect the corresponding amplitude and phase data there, and this process is repeated until the acquisition of the amplitude and phase data of M radiation units is completed; the receiving amplitude and phase of the M T / R channels are made consistent with the target value; and the amplitude control word and phase control word of the M T / R channels are obtained.

[0054] The correction method of the open-loop receiving phase matching pattern of the present application controls the corresponding radiating unit to work and other radiating units to standby; when the amplitude and phase are consistent with the target value, the amplitude control word and the phase control word of all radiating units are obtained in sequence; then the software simulation in the non-cascade state is performed to obtain the first scattering matrix and the second scattering matrix of all radiating units at the same phase matching frequency point; finally, by selecting a unit under test in sequence, the additional amplitude and the additional phase value are obtained according to the complex current, and the additional amplitude and the additional phase value are subtracted to obtain the new amplitude control word and the phase control word; the method of patrolling the additional complex current can quickly remove the influence of other radiating units on the unit under test, so as to accurately and quickly obtain the new amplitude control word and the phase control word. The correction can be completed without iteration, and there will be no situation where the iteration does not converge. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solution provided by the present application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present application.

[0056] Figure 1 This is a schematic diagram of the overall process of this application;

[0057] Figure 2 This is a schematic diagram of the open-loop matching environment for this application;

[0058] Figure 3 This is a schematic diagram of the normalized weights of the azimuth amplitude of a certain antenna in this application;

[0059] Figure 4 This is the directional diagram measured in the test field after the open-loop phase matching of this application;

[0060] Figure 5 This is the azimuth amplitude target value curve diagram after correction for this application;

[0061] Figure 6 This is the azimuth phase target value curve diagram after correction for this application;

[0062] Figure 7 The directivity pattern measured at the test field after adding correction values ​​for this application. DETAILED DESCRIPTION

[0063] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0064] A method for correcting an open-loop receiving phase pattern, assuming that the antenna is an active phased array antenna with M T / R channels, such as Figure 1 , specifically including the following steps:

[0065] Step S100, build a phase matching environment, control the probe to move to the front of each radiating unit in turn, control the corresponding radiating unit to work and other radiating units to standby; when the amplitude and phase are consistent with the target value, obtain the amplitude control word and phase control word of all radiating units in turn;

[0066] The specific steps include:

[0067] Step S110, sequentially configure the power supply, PC host, vector network analyzer, active phased array antenna and movable probe, build a phase matching environment, and connect the instruments;

[0068] Step S120, controlling the movable probe to move to the front of the first radiation unit through the PC host;

[0069] Step S130, controlling the receiving operation of the first radiation unit of the T / R component through the PC host, and the other T / R channels are in a receiving standby state;

[0070] Step S140, collecting amplitude and phase data of the vector network analyzer through the PC host;

[0071] Step S150, controlling the amplitude and phase of the first T / R component through the PC host to make them consistent with the target value;

[0072] Step S160, control the movable probe to move to the next radiation unit through the PC host and collect the corresponding amplitude and phase data there, and repeat this process until the amplitude and phase data of M radiation units are collected; make the received amplitude and phase of M T / R channels consistent with the target value; and obtain the amplitude control word and phase control word of M T / R channels.

[0073] Preferably, combined Figure 2 , the specific method of obtaining the amplitude control word and phase control word of all radiating units in turn is:

[0074] Configure the power supply, PC host, vector network analyzer, active phased array antenna and movable probe in sequence, build the matching environment, and connect the instruments;

[0075] The movable probe is controlled by the PC host to move to the front of the first radiation unit;

[0076] The receiving work of the first radiation unit of the T / R component is controlled by the PC host, and other T / R channels are in the receiving standby state;

[0077] Collect amplitude and phase data of vector network analyzer through PC host;

[0078] The amplitude and phase of the first T / R component are controlled by the PC host to be consistent with the target value;

[0079] The movable probe is controlled by the PC host to move to the next radiation unit and collect the corresponding amplitude and phase data there, and this process is repeated until the acquisition of the amplitude and phase data of M radiation units is completed; the receiving amplitude and phase of the M T / R channels are made consistent with the target value; and the amplitude control word and phase control word of the M T / R channels are obtained.

[0080] Through the above design, accurate extraction of amplitude control words and phase control words can be achieved.

[0081] Step S200, perform software simulation in a non-cascaded state to obtain the first scattering matrix S1 of all radiating units at the same matching frequency point; then cascade each radiating unit, and calculate the second scattering matrix S of all radiating units according to the reflection coefficient of each cascade channel. new ;

[0082] Preferably, the first scattering matrix S1 is obtained by:

[0083] Select a simulation software to model the real environment of the antenna array, set the same working frequency for the radiating units, simulate the array composed of the radiating units, and then directly obtain the first scattering matrix of all radiating units at the same matching frequency through the existing test method, which is accurate and efficient. The first scattering matrix S1 is an M×M complex matrix.

[0084] Preferably, the second scattering matrix S new The method to obtain is:

[0085] Convert the first scattering matrix into a first impedance matrix Z1;

[0086] Test the first reflection coefficient S of the T / R component channel corresponding to M radiation units tr ;

[0087] According to the first reflection coefficient S of the T / R component channel tr Calculate the port impedance Z of each T / R component channel in standby state tr ;

[0088] Pair port impedance Z tr Normalize and get the diagonal matrix Z tr1 ;

[0089] According to the diagonal matrix Z tr1 The impedance matrix Z1 is used to calculate the second impedance matrix Z after the radiator is cascaded with T / R components. new ;

[0090] According to the impedance matrix Z new Calculate the second scattering matrix S after the radiation unit cascades the T / R components new .

[0091] Preferably, the calculation formula of the first impedance matrix Z1 is: Z1 = (U + S1) * (U - S1) -1 , where U is the M×M unit matrix and M is the number of radiation units;

[0092] Port impedance Z tr The calculation formula is: tr =(1+S tr ). / (1-S tr ), Z tr is an M×1 complex matrix;

[0093] Diagonal matrix Z tr1 The calculation formula is: tr1 (n, n) = suqr(Z tr (n)), the value range of n is 1 to M;

[0094] The second impedance matrix Z new The calculation formula is: new =Z tr1 -1 *Z1*Z tr1 -1 *50; Since the first scattering matrix S1 is normalized to 50Ω, the second impedance matrix Z after cascading is calculated new Need to multiply by 50.

[0095] The second scattering matrix S new The method to obtain S is: new =(Z new +U) -1 *(Z new -U).

[0096] By obtaining the first scattering matrix S1 and the second scattering matrix S new , can accurately determine the working data of all radiation units.

[0097] Step S300, calculating the second reflection coefficients of all radiation units according to the second scattering matrix of all radiation units, selecting a unit to be measured in turn, and calculating the complex current I added to the unit to be measured by other radiation units according to the reflection coefficient n , obtain additional amplitude and additional phase values ​​according to the complex current, and subtract the additional amplitude and additional phase values ​​from the amplitude control word and the phase control word to obtain new amplitude control word and phase control word.

[0098] The amplitude control word and phase control word are subtracted from the additional amplitude and additional phase values ​​to obtain new amplitude control words and phase control words. The reason is that if the amplitude and phase control words of the T / R component are positive values, the amplitude and phase will become smaller.

[0099] Preferably, the method for obtaining the second reflection coefficient ss is:

[0100] Move the probe to the front of the nth radiation unit. The distance from the probe to the nth radiation unit is d, and the value range of n is 1 to M.

[0101] Calculate the distance d1 from the transmitting probe to the M radiation units, where d1 is an M×1 matrix;

[0102] Calculate the first phase value from the transmitting probe to each radiating unit according to the distance d1 in is an M×1 matrix;

[0103] According to the first phase value of each radiating unit Calculate the second reflection coefficient ss of the M radiation elements, ss is an M×1 matrix, where ss(n)=S new (n, n).

[0104] Preferably, the complex current I added by other radiating units to the unit under test n The specific calculation method is:

[0105] The second scattering matrix S of all radiation units new Remove the row number of the unit under test and get the third scattering matrix S new1 ;

[0106] The first phase value from the transmitting probe to each radiating element Subtract the row number of the unit under test from the value to get the second phase value

[0107] Calculate the third reflection coefficient ss1 of the units except the nth radiation unit;

[0108] Calculate the complex current I added to the radiation element n in addition to other radiation elements n .

[0109] Preferably, the third scattering matrix S is calculated in matlab new1 , the specific formula is:

[0110] S new1 =S new

[0111] S new1 (n,:) = []

[0112] Among them, [] means removing all columns of the nth row;

[0113] Calculate second phase value in matlab The specific formula is:

[0114]

[0115] Calculate the third reflection coefficient ss1 in Matlab. The specific formula is:

[0116] ss1=ss

[0117] ss1(n)=[].

[0118] Preferably, the calculation formula of the additional amplitude and the additional phase value is:

[0119] Where abs is the absolute value calculation, and angle is the angle calculation.

[0120] In summary, the present application controls the corresponding radiation unit to work and other radiation units to standby; when the amplitude and phase are consistent with the target value, the amplitude control word and phase control word of all radiation units are obtained in sequence; then the software simulation is performed in a non-cascaded state to obtain the first scattering matrix and the second scattering matrix of all radiation units at the same phase matching frequency point; finally, by selecting a unit under test in sequence, the additional amplitude and additional phase value are obtained according to the complex current, and the additional amplitude and additional phase value are subtracted to obtain the new amplitude control word and phase control word; the method of patrolling the additional complex current can quickly remove the influence of other radiation units on the unit under test, so as to accurately and quickly obtain the new amplitude control word and phase control word. The correction can be completed without iteration, and there will be no situation where the iteration does not converge.

[0121] The following is a specific example to illustrate that, taking a certain antenna as an example, the directional pattern after open-loop phase matching is corrected, and the unit excitation phase is equal, and the amplitude normalization weight is as follows Figure 3 As shown;

[0122] The directional diagram measured in the test field after open-loop phase matching is as follows: Figure 4 As shown;

[0123] The corrected azimuth amplitude and phase target value curves are as follows: Figure 5 and Figure 6 As shown:

[0124] After adding the correction value, the directional diagram measured in the test field is as follows: Figure 7 As shown:

[0125] Therefore, it can be seen that the method is used to correct the radiation pattern so that the tested radiation pattern sidelobe level is basically consistent with the theory. The theoretical maximum sidelobe level of this antenna radiation pattern is -30dB, and the maximum sidelobe level of the radiation pattern after open-loop phase matching is -26.97dB. After increasing the correction amount, the maximum sidelobe level of the radiation pattern is -29.34dB. Especially in the case of strong mutual coupling, the improvement of the maximum level is better.

[0126] Finally, it should be noted that: the drawings of the embodiments disclosed in the present invention only involve structures related to the embodiments disclosed in the present invention, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other;

[0127] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for correcting an open-loop receiving phase matching pattern, characterized in that: include: Build a matching environment, control the probe to move to the front of each radiation unit in turn, control the corresponding radiation unit to work, and other radiation units to standby; When the amplitude and phase are consistent with the target value, the amplitude control words and phase control words of all the radiating units are obtained in sequence; Perform software simulation in a non-cascaded state to obtain the first scattering matrix S1 of all radiation units at the same phase matching frequency point; Then, each radiation unit is cascaded, and the second scattering matrix s of all radiation units is calculated according to the reflection coefficient of each cascade channel. new ; The second reflection coefficients of all radiation units are calculated according to the second scattering matrix of all radiation units, and a unit to be measured is selected in turn, and the complex current I added to the unit to be measured by other radiation units is calculated according to the reflection coefficient. n , obtain additional amplitude and additional phase values ​​according to the complex current, and subtract the additional amplitude and additional phase values ​​from the amplitude control word and the phase control word to obtain new amplitude control word and phase control word.

2. The method for correcting the open-loop receiving phase matching pattern according to claim 1, characterized in that: The method for obtaining the first scattering matrix S1 is: Select a simulation software to model the real environment of the antenna array. By setting the same operating frequency point for the radiating elements, simulate and test the array composed of the radiating elements to obtain the first scattering matrix of all radiating elements at the same matching frequency point.

3. The method for correcting the open-loop receiving phase matching pattern according to claim 1, characterized in that: The second scattering matrix s new The method to obtain is: Convert the first scattering matrix into a first impedance matrix Z1; Test the first reflection coefficient S of the T / R component channel corresponding to M radiation units tr ; According to the first reflection coefficient S of the T / R component channel tr Calculate the port impedance Z of each T / R component channel in standby state tr ; Port impedance Z tr Normalize and get the diagonal matrix Z tr1 ; According to the diagonal matrix Z tr1 The impedance matrix Z1 is used to calculate the second impedance matrix Z after the radiator is cascaded with T / R components. new ; According to the impedance matrix Z new Calculate the second scattering matrix S after the radiation unit cascades the T / R components new .

4. The method for correcting the open-loop receiving phase matching pattern as claimed in claim 3, characterized in that: The calculation formula of the first impedance matrix Z1 is: Z1 = (U + S1) * (U - S1) -1 , where U is the M×M unit matrix, and M is the number of radiation units; The port impedance z tr The calculation formula is: tr (1+S tr ). / (1-S tr ), z tr is an M×1 complex matrix; The diagonal matrix Z tr1 The calculation formula is: tr1 (m,n)=suqr(Z tr (n)), the value range of n is 1 to M; The second impedance matrix Z new The calculation formula is: new =Z tr1 -1 *Z1*Z tr1 -1 *50; The second scattering matrix S new The method to obtain S is: new =(Z new +U) -1 *(Z new -U).

5. The method for correcting the open-loop receiving phase matching pattern as claimed in claim 1, characterized in that: The method for obtaining the second reflection coefficient ss is: Move the probe to the front of the nth radiation unit. The distance from the probe to the nth radiation unit is d, and the value range of n is 1 to M. Calculate the distance d1 from the transmitting probe to the M radiation units, where d1 is an M×1 matrix; Calculate the first phase value from the transmitting probe to each radiating unit according to the distance d1 in is an M×1 matrix; According to the first phase value of each radiating unit Calculate the second reflection coefficient ss of the M radiation elements, ss is an M×1 matrix, where ss(n)=S new (n, n).

6. The method for correcting the open-loop receiving phase matching pattern as claimed in claim 5, characterized in that: The other radiating units add a complex current I to the unit under test n The specific calculation method is: The second scattering matrix S of all radiation units new Remove the row number of the unit under test and get the third scattering matrix S new1 ; The first phase value from the transmitting probe to each radiating unit Subtract the row number of the unit under test from the value to get the second phase value Calculate the third reflection coefficient ss1 of the units except the nth radiation unit; Calculate the complex current I added to the radiation element n in addition to other radiation elements n .

7. The method for correcting the open-loop receiving phase matching pattern according to claim 6, characterized in that: Calculate the third scattering matrix S in Matlab new1 The formula is: S new1 =S new S new1 (n,:)=[] Among them, [] means removing all columns of the nth row; Calculate the second phase value in matlab The formula is: The formula for calculating the third reflection coefficient ss1 in Matlab is: ss1=ss ss1(n)=[].

8. The method for correcting the open-loop receiving phase matching pattern as claimed in claim 1, characterized in that: The calculation formula of the additional amplitude and additional phase value is: Ia add =20*log 10 abs(I n ) Pa add =angle(I n )*180 / π; where abs is the absolute value calculation and angle is the angle calculation.

9. The method for correcting the open-loop receiving phase matching pattern according to claim 1, characterized in that: The specific method of sequentially acquiring the amplitude control words and phase control words of all radiating units is: Configure the power supply, PC host, vector network analyzer, active phased array antenna and movable probe in sequence, build the matching environment, and connect the instruments; The movable probe is controlled by the PC host to move to the front of the first radiation unit; The receiving work of the first radiation unit of the T / R component is controlled by the PC host, and other T / R channels are in the receiving standby state; Collect amplitude and phase data of vector network analyzer through PC host; The amplitude and phase of the first T / R component are controlled by the PC host to be consistent with the target value; The movable probe is controlled by the PC host to move to the next radiation unit and collect the corresponding amplitude and phase data there, and this process is repeated until the amplitude and phase data of M radiation units are collected; the receiving amplitude and phase of M T / R channels are consistent with the target value; The amplitude control words and phase control words of the M T / R channels are obtained.

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