Emission phased array calibration method and system

Abstract

The transmitting phased array calibration method comprises the following steps of: under an external field and far field test condition, arranging a standard horn antenna in a central normal direction of a transmitting phased array; selecting one of all channels for transmitting the phased array as a reference channel, and taking the other channels as to-be-detected channels; testing the channel synthesis power of the reference channel and the to-be-tested channel in a plurality of different basic phases one by one; calculating a theoretical whole array synthesis power of the transmitting phased array based on the synthesis power of all the channels; and testing the whole array maximum radiation power of the transmitting phased array, comparing the whole array maximum radiation power with a theoretical whole array synthesis power, if an error is smaller than a preset difference threshold value, ending calibration, and otherwise, determining a phase deviation value of the to-be-tested channel relative to the reference channel through phase search by taking the reference channel as a reference. According to the emission phased array calibration method and system provided by the invention, the test process is simpler and more feasible, and the power consumption and heat consumption of the whole machine are smaller.

Description

Technical Field

[0001] The present invention relates to the technical field of transmitting phased arrays, and in particular to a transmitting phased array calibration method and system. Background Art

[0002] As some jammers' requirements for equivalent radiated power increase, their transmitting arrays often use phased array antennas as the RF front end, and precise control of the amplitude and phase of the transmitting array antenna units is the key to improving the gain coefficient and beam scanning performance of the phased array system. Since the array of the transmitting channel also belongs to the phased array system, the mutual coupling method, phase commutation method, and rotation vector method for phase calibration of the phased array channel in the existing technology are also applicable.

[0003] Among several existing technologies, the mutual coupling method requires a separate coupling loop within the system and a calibration control unit. The system design is complex and highly professional. The phase-changing method obtains the initial amplitude and phase information based on the linear equations composed of the antenna radiation pattern measured under far-field conditions. The formula derivation and theoretical calculation used are relatively complex, and a certain theoretical foundation is required in program logic design. The classic rotating vector method needs to traverse all phase shifter states to find the minimum and maximum values ​​of the combined power and the corresponding phase compensation. The test sample size is large and the test time is long.

[0004] In summary, the existing methods all have certain shortcomings. Although there are some improved solutions in the prior art, they are mainly for phase adjustment of sub-arrays or the entire array. The calibration test process requires all power amplifiers to be turned on, and the power consumption, heat consumption and power of the whole machine are relatively large. In particular, the large radiation power is likely to pose a threat to the frequency use of other infrastructure. Summary of the invention

[0005] In order to solve the deficiencies in the prior art, the present invention provides a transmitting phased array calibration method and system, the testing process is simpler and easier, and the power consumption and heat consumption of the whole machine are relatively small.

[0006] In order to achieve the above object, the specific scheme adopted by the present invention is: a transmitting phased array calibration method, comprising the following steps: Under outdoor far-field test conditions, the standard horn antenna is set in the center normal direction of the transmitting phased array; Select one of all the channels of the transmitting phased array as a reference channel, and use the remaining channels as channels to be tested; Test the channel synthesis power of the reference channel and the channel to be tested one by one under multiple different basic phases; Calculate the theoretical total array composite power of the transmitting phased array based on the composite power of all channels; The maximum radiated power of the entire transmitting phased array is tested and compared with the theoretical composite power of the entire array. If the error is less than the preset difference threshold, the calibration is terminated. Otherwise, the phase deviation value of the channel to be tested relative to the reference channel is determined through phase search with the reference channel as a reference.

[0007] As a further optimization of the above-mentioned transmit phased array calibration method: the method for determining the setting position of the standard horn antenna includes: The center position of the transmitting phased array antenna and the attitude parameters of the standard horn antenna are calculated by the GNSS baseline solution method. The attitude parameters include the absolute azimuth angle, pitch angle and baseline length. Set the standard horn antenna to the center of the antenna; Drive the transmitting phased array to rotate in the same direction as the standard horn antenna based on the absolute azimuth angle; The relative height difference between the transmitting phased array and the standard horn antenna is calculated based on the pitch angle and the baseline height, and the standard horn antenna is adjusted according to the relative height difference until the center heights of the standard horn antenna and the transmitting phased array are consistent.

[0008] As a further optimization of the above-mentioned transmit phased array calibration method: a method of selecting one of all channels of the transmit phased array as a reference channel includes: Conduct power radiation test on the entire transmitting phased array and record the power amplifier status of all channels; A channel located at the center of the transmitting phased array is used as the reference channel.

[0009] As a further optimization of the above-mentioned transmit phased array calibration method, a specific method for testing the channel composite power of the reference channel and the channel to be tested one by one under multiple different basic phases includes: Determine the initial phase of all channels; Determine a plurality of basic phases corresponding to the channels to be measured based on the initial phase and a preset first phase step; Start the reference channel and a channel to be tested at the same time; Adjust the phase of the channel to be tested to the basic phase, and calculate the channel composite power of the reference channel and the channel to be tested under each basic phase; All channels to be tested are traversed until the channel composite power corresponding to all channels to be tested is obtained.

[0010] As a further optimization of the above-mentioned transmit phased array calibration method: after obtaining the channel composite power corresponding to the channel to be measured, the phase compensation value of the channel to be measured is calculated based on all channel composite powers corresponding to the channel to be measured, and phase compensation is performed on the channel to be measured based on the phase compensation value.

[0011] As a further optimization of the above-mentioned transmit phased array calibration method: the first phase step is set to 90°, and the channel composite power is recorded as P1, P2, P3, and P4; The method for calculating the phase compensation value is:

[0012] As a further optimization of the above-mentioned transmit phased array calibration method: a method for calculating the theoretical whole array composite power of the transmit phased array based on the composite power of all channels includes: Start the reference channel and all channels to be tested to run at full power; The theoretical array composite power is calculated based on the phase compensation value.

[0013] As a further optimization of the above-mentioned transmit phased array calibration method: a method for determining the phase deviation value of the channel to be measured relative to the reference channel through phase search with the reference channel as a reference includes: Measure the two-phase composite power of the channel under test at phase increments of 0°, 90°, 180° and 270°, and take the maximum value as the first two-phase composite power P1(max); Taking the phase increment Δ1 of the first two-pass combined power P1(max) as the center, searching for the second two-pass combined power P2(max) within the first interval with a preset adjustment step size; Taking the phase increment Δ2 of the second two-element composite power P2(max) as the center, search for the third two-element composite power P3(max) in the second interval; The phase increment Δ3 of the third 2-element composite power P3(max) relative to the second 2-element composite power P2(max) is calculated and used as the phase deviation value of the channel to be measured.

[0014] As a further optimization of the above-mentioned transmit phased array calibration method: the difference threshold is set to 0.5dB.

[0015] A transmitting phased array calibration system is used to implement the above-mentioned transmitting phased array calibration method, and the system comprises: Signal terminal, used to control the transmitting phased array; A spectrum analyzer, used to obtain spectrum data of radiation signals emitted by the transmitting phased array; The computer is used to send control instructions to the signal terminal and calculate the channel synthesis power, theoretical whole array synthesis power, whole array maximum radiation power and phase deviation value based on the radiation signal spectrum data.

[0016] Beneficial effects: The present invention can complete the phase calibration of large-array phased array equipment only through a spectrum analyzer. The test process is simple and easy to design and implement, without the need to add additional equipment and expansion means. The present invention only turns on the power amplifiers of two channels during the calibration process, and uses low-power calibration and high-power verification to reduce the power of long-term frequency use to a minimum, which can meet the frequency management requirements under certain conditions and can also reduce electromagnetic radiation to the human body. During the calibration process of the present invention, the power consumption and heat consumption of the whole machine are relatively small, which is beneficial to the protection of the channel power amplifier radio frequency unit and avoids irreversible hardware loss caused by long-term high-temperature operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall process of the method of the present invention; Figure 2 is a schematic diagram of the phase search process. DETAILED DESCRIPTION

[0018] 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.

[0019] like Figure 1 As shown, a transmit phased array calibration method includes S1 to S5.

[0020] S1. Under the outdoor far-field test conditions, the standard horn antenna is set in the center normal direction of the transmitting phased array. Through this setting, the standard horn antenna can accurately receive the electromagnetic waves output by the transmitting phased array, ensuring the accuracy of the calibration results. All channels of the transmitting phased array can be evenly divided into 2n sub-arrays. If the total number of channels is less than an integer multiple of 2, the actual remaining channels are counted as 1 sub-array.

[0021] The method for determining the setting position of the standard horn antenna includes S11 to S14.

[0022] S11. Calculate the center position of the transmitting phased array antenna and the attitude parameters of the standard horn antenna through the GNSS baseline solution method. The attitude parameters include the absolute azimuth angle, the pitch angle and the baseline length.

[0023] S12. Set the standard horn antenna to the center of the antenna.

[0024] S13. Drive the transmitting phased array to rotate in the same direction as the standard horn antenna based on the absolute azimuth angle.

[0025] S14. Calculate the relative height difference between the transmitting phased array and the standard horn antenna based on the pitch angle and the baseline height, and adjust the standard horn antenna according to the relative height difference until the center heights of the standard horn antenna and the transmitting phased array are consistent.

[0026] S2. Select one of all channels of the transmitting phased array as a reference channel, and use the remaining channels as channels to be tested. The specific method includes S21 to S22.

[0027] S21. Perform a power radiation test on the entire transmitting phased array and record the power amplifier status of all channels.

[0028] S22. Use a channel located at the center of the transmitting phased array as a reference channel.

[0029] S3. Testing the channel synthesis power of the reference channel and the channel to be tested one by one under multiple different basic phases. The specific method includes S31 to S35.

[0030] S31, determine the initial phase of all channels, the initial phase can be obtained from the phase shifter, and the initial phase of all channels can be combined to create an initial phase table. On the other hand, parameters such as the power amplifier radiation power and startup time of each channel can also be set.

[0031] S32, determining multiple basic phases corresponding to the channels to be measured based on the initial phase and the preset first phase step. The first phase step is set to 90°, and the phase of the channels to be measured is increased by 180°, 0°, 90° and 270° in sequence based on the initial phase and the first phase step.

[0032] S33. Start a reference channel and a channel to be tested at the same time.

[0033] S34, adjusting the phase of the channel to be measured to the basic phase, and calculating the channel composite power of the reference channel and the channel to be measured at each basic phase, and the obtained channel composite power is recorded as P1, P2, P3, and P4.

[0034] S35, traversing all channels to be tested until the channel composite powers corresponding to all channels to be tested are obtained.

[0035] Further, after the channel composite power corresponding to the channel to be measured is obtained, the phase compensation value of the channel to be measured is calculated based on the composite power of all channels corresponding to the channel to be measured, and the phase compensation is performed on the channel to be measured based on the phase compensation value. The method for calculating the phase compensation value is:

[0036] After using the phase compensation value to perform phase compensation on the channel to be measured, a total phase value structure consistent with the reference channel can be obtained.

[0037] S4. Calculate the theoretical whole array composite power of the transmitting phased array based on the composite power of all channels. The method for calculating the theoretical whole array composite power of the transmitting phased array based on the composite power of all channels includes S41 to S42.

[0038] S41, start the reference channel and all channels to be tested to run at full power.

[0039] S42. Calculate theoretical whole array composite power based on the phase compensation value.

[0040] like Figure 2 As shown, S5, the maximum radiated power of the entire array of the transmitting phased array is tested and compared with the theoretical entire array composite power. If the error is less than a preset difference threshold, the calibration is terminated, and the difference threshold is set to 0.5dB. Otherwise, the phase deviation value of the channel to be tested relative to the reference channel is determined by phase search with reference to the reference channel. The method for determining the phase deviation value of the channel to be tested relative to the reference channel by phase search with reference to the reference channel includes S51 to S54.

[0041] S51, measuring the two-phase composite power of the channel to be tested when the phase increments are 0°, 90°, 180° and 270°, and taking the maximum value thereof as the first two-phase composite power P1(max).

[0042] S52, taking the phase increment Δ1 of the first two-pass combined power P1(max) as the center, search for the second two-pass combined power P2(max) in the first interval with a preset adjustment step. The first interval is set to [Δ1+45°, Δ1-45°], and the preset adjustment step is set to 10°.

[0043] S53, taking the phase increment Δ2 of the second two-element composite power P2(max) as the center, search for the third two-element composite power P3(max) in the second interval. The second interval is set to [Δ2+5°, Δ2-5°].

[0044] S54, calculate the phase increment Δ3 of the third two-element composite power P3(max) relative to the second two-element composite power P2(max), and use it as the phase deviation value of the channel to be measured. Then, use the phase deviation value to calibrate the phase of the channel to be measured.

[0045] Furthermore, the maximum radiated power of the entire array after phase calibration is tested and compared with the theoretical entire array composite power. If the error exceeds 1 dB, S5 is re-executed, and the adjustment step is set to 5°, and the second interval is set to [Δ2+2.5°, Δ2-2.5°].

[0046] The present invention can complete the phase calibration of large-array phased array equipment only through a spectrum analyzer, and the test process is simple and easy to design and implement, without adding additional equipment and expansion means; the present invention only turns on the power amplifiers of two channels during the calibration process, and uses low-power calibration and high-power verification to reduce the power of long-term frequency use to a minimum, which can meet the frequency management requirements under certain conditions and can also reduce electromagnetic radiation to the human body; during the calibration process of the present invention, the power consumption and heat consumption of the whole machine are small, which is beneficial to the protection of the channel power amplifier radio frequency unit and avoids irreversible hardware loss caused by long-term high-temperature operation.

[0047] The present invention further provides a transmitting phased array calibration system for implementing the above-mentioned transmitting phased array calibration method. The system includes a signal terminal, a spectrum analyzer and a computer.

[0048] Signal terminal, used to control the transmitting phased array.

[0049] A spectrum analyzer is used to obtain spectrum data of radiation signals emitted by the transmitting phased array.

[0050] The computer is used to send control instructions to the signal terminal, and calculate the channel synthesis power, theoretical whole array synthesis power, whole array maximum radiation power and phase deviation value based on the radiation signal spectrum data. The above description of the disclosed embodiments enables professionals and technicians in this field to implement or use the present invention. Various modifications to these embodiments will be obvious to professionals and technicians in this field, and the general principles defined in this article can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown in this article, but will conform to the widest range consistent with the principles and novel features disclosed in this article.

Claims

1. A transmit phased array calibration method, characterized in that: The steps include: Under outdoor far-field test conditions, the standard horn antenna is set in the center normal direction of the transmitting phased array; Select one of all the channels of the transmitting phased array as a reference channel, and use the remaining channels as channels to be tested; Test the channel synthesis power of the reference channel and the channel to be tested one by one under multiple different basic phases; Calculate the theoretical total array composite power of the transmitting phased array based on the composite power of all channels; The maximum radiated power of the entire transmitting phased array is tested and compared with the theoretical composite power of the entire array. If the error is less than the preset difference threshold, the calibration is terminated. Otherwise, the phase deviation value of the channel to be tested relative to the reference channel is determined through phase search with the reference channel as a reference.

2. A transmit phased array calibration method as claimed in claim 1, characterized in that: Methods for determining the location of standard horn antenna settings include: The center position of the transmitting phased array antenna and the attitude parameters of the standard horn antenna are calculated by the GNSS baseline solution method. The attitude parameters include the absolute azimuth angle, pitch angle and baseline length. Set the standard horn antenna to the center of the antenna; Drive the transmitting phased array to rotate in the same direction as the standard horn antenna based on the absolute azimuth angle; The relative height difference between the transmitting phased array and the standard horn antenna is calculated based on the pitch angle and the baseline height, and the standard horn antenna is adjusted according to the relative height difference until the center heights of the standard horn antenna and the transmitting phased array are consistent.

3. A transmit phased array calibration method as claimed in claim 1, characterized in that: Methods for selecting one of all channels of the transmitting phased array as a reference channel include: Conduct power radiation test on the entire transmitting phased array and record the power amplifier status of all channels; A channel located at the center of the transmitting phased array is used as the reference channel.

4. A transmit phased array calibration method as claimed in claim 1, characterized in that: The specific method of testing the channel synthesis power of the reference channel and the channel to be tested one by one under multiple different basic phases includes: Determine the initial phase of all channels; Determine a plurality of basic phases corresponding to the channels to be measured based on the initial phase and a preset first phase step; Start the reference channel and a channel to be tested at the same time; Adjust the phase of the channel to be tested to the basic phase, and calculate the channel composite power of the reference channel and the channel to be tested under each basic phase; All channels to be tested are traversed until the channel composite power corresponding to all channels to be tested is obtained.

5. A transmit phased array calibration method as claimed in claim 4, characterized in that: After the channel composite power corresponding to the channel to be measured is obtained, a phase compensation value of the channel to be measured is calculated based on all channel composite powers corresponding to the channel to be measured, and phase compensation is performed on the channel to be measured based on the phase compensation value.

6. A transmit phased array calibration method as claimed in claim 5, characterized in that: The first phase step is set to 90°, and the channel composite power is recorded as P1, P2, P3, and P4; The method for calculating the phase compensation value is:

7. A transmit phased array calibration method as claimed in claim 5, characterized in that: The method of calculating the theoretical whole array combined power of the transmitting phased array based on the combined power of all channels includes: Start the reference channel and all channels to be tested to run at full power; The theoretical array composite power is calculated based on the phase compensation value.

8. A transmit phased array calibration method as claimed in claim 4, characterized in that: The method for determining the phase deviation value of the channel to be tested relative to the reference channel through phase search with the reference channel as a reference includes: Measure the two-phase composite power of the channel under test at phase increments of 0°, 90°, 180° and 270°, and take the maximum value as the first two-phase composite power P1(max); Taking the phase increment Δ1 of the first two-pass combined power P1(max) as the center, searching for the second two-pass combined power P2(max) within the first interval with a preset adjustment step size; Taking the phase increment Δ2 of the second two-element composite power P2(max) as the center, search for the third two-element composite power P3(max) in the second interval; The phase increment Δ3 of the third 2-element composite power P3(max) relative to the second 2-element composite power P2(max) is calculated and used as the phase deviation value of the channel to be measured.

9. A transmit phased array calibration method as claimed in claim 1, characterized in that: The difference threshold was set to 0.5dB.

10. A transmitting phased array calibration system, characterized in that: Used to implement a transmit phased array calibration method as described in any one of claims 1 to 9, the system comprising: Signal terminal, used to control the transmitting phased array; A spectrum analyzer, used to obtain spectrum data of radiation signals emitted by the transmitting phased array; The computer is used to send control instructions to the signal terminal and calculate the channel synthesis power, theoretical whole array synthesis power, whole array maximum radiation power and phase deviation value based on the radiation signal spectrum data.

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