Radio frequency multi-channel amplitude-phase calibration method based on full-automatic error variable

Abstract

The invention provides a radio frequency multichannel amplitude-phase calibration method based on a full-automatic error variable, and the method comprises the steps: carrying out the length-set sampling data of the amplitude of a real-time signal, carrying out the fast Fourier transform, and carrying out the amplitude-phase error estimation, thereby forming a full-automatic error variable reference, and carrying out the calibration of the amplitude-phase of the full-automatic error variable. Therefore, the automatic calibration of the amplitude phase error between the channels is conveniently and quickly realized, the calibration precision is high, the amplitude and phase difference between the channels can be effectively eliminated, the directivity accuracy of the system beam is ensured, and the evaluation system is ensured to simulate the orientation, distance and other related information of the target according to actual combat requirements. And rapid and efficient evaluation on the receiving and transmitting channel performance of the radar can be realized.

Description

Technical Field

[0001] The invention relates to the field of phased array radar, and in particular to a radio frequency multi-channel amplitude and phase calibration method based on full-automatic error variables. Background Art

[0002] Under modern information battlefield conditions, with the repeated use of phased array radars in actual battlefields, various environmental influences such as device aging have caused the performance of the transmitting and receiving channels of phased array radars to decline. In addition, most of the current phased array radar transmitting and receiving channels are calibrated based on their own system channels to ensure the normal operation of the transmitting and receiving channels. The calibration accuracy is not high, and there is a lack of simulated targets based on actual combat requirements to evaluate the function and performance of the system's transmitting and receiving channels. In addition, on the basis of providing the calibration function, it is also necessary to provide a fast and efficient automated evaluation system to quickly evaluate and detect its performance, which can quickly locate system faults, thereby reducing equipment maintenance cycles and improving monitoring efficiency. Summary of the invention

[0003] In view of this, the purpose of the present invention is to provide a RF multi-channel amplitude and phase calibration method based on fully automatic error variables, which can overcome the problems existing in the background technology and has high calibration accuracy. At the same time, this method can also be used for rapid performance evaluation and detection of phased array radar systems.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] The RF multi-channel amplitude and phase calibration method based on fully automatic error variables is used for RF multi-channel amplitude and phase calibration of a phased array radar system. The method includes fully automatic variable generation, that is, data sampling of real-time signal amplitudes is performed through multiple data acquisition channels, and then fast Fourier transform is performed on the sampled data and amplitude and phase error estimation is performed, thereby forming a fully automatic error variable benchmark, and the error variable benchmark is stored in real time;

[0006] After selecting the calibration mode, the transmitting channel calibration and the receiving channel calibration are performed. First, the channel signal amplitude value and the real-time signal amplitude over a period of time are sampled for a certain length of data, and a fast Fourier transform is performed on them and the amplitude and phase errors are estimated. A fully automatic error variable benchmark is formed for horizontal comparison to obtain a difference, which forms a calibration compensation factor and performs real-time correction on the channel amplitude calibration value.

[0007] Furthermore, after multiple samplings, the values ​​generated by the automatic variables are averaged multiple times to obtain a high-precision real-time calibration compensation factor, which can reduce the error of the calibration compensation value.

[0008] Further, the receiving channel calibration includes: controlling each channel to enter a receiving mode through a processor, controlling the calibration channel to generate a calibration signal, and the calibration signal enters each receiving channel through a power splitter coupler;

[0009] The receiving channel sends the received intermediate frequency signal to AD for sampling, converts the analog signal into a digital signal, and completes signal processing to obtain the amplitude and phase of each channel;

[0010] Since the amplitude and phase of the calibration signal generated by the calibration channel are constant values, the amplitude and phase calibration values ​​corresponding to each channel can be calculated based on the amplitude and phase information of each channel, and an amplitude and phase calibration table can be established. The calibration information is stored in the memory. Each time the receiving channel is calibrated thereafter, the calibration value corrected by the calibration factor is automatically read to achieve channel amplitude and phase compensation and ensure channel amplitude and phase consistency.

[0011] Further, the transmission channel calibration includes: controlling one of the multiple channels through a processor to send out a radio frequency signal, which enters the calibration channel through a power amplifier coupler;

[0012] The intermediate frequency signal is sampled in sequence, and the analog signal is converted into a digital signal. After corresponding processing, the amplitude and phase information of the transmitting channel are obtained. According to the above steps, the amplitude and phase information of multiple channels are collected in sequence;

[0013] Then, the required amplitude and phase calibration values ​​are calculated based on the amplitude and phase information of all channels, and an amplitude and phase calibration table is established. At the same time, the calibration information is stored in the memory. Each time the transmit channel is calibrated, the calibration value corrected by the calibration factor is automatically read to achieve channel amplitude and phase compensation and ensure channel amplitude and phase consistency.

[0014] Furthermore, when the phased array radar system stops working, the fully automatic variable generation and collection work is performed by setting a timing, and the fully automatic variables are updated in real time at a regular interval to ensure the high accuracy of the calibration compensation factor.

[0015] Furthermore, the amplitude and phase calibration tables obtained during the calibration process are used to quickly evaluate the performance of the radar's receiving and transmitting channels.

[0016] The beneficial effects of the present invention are:

[0017] The radio frequency multi-channel amplitude and phase calibration method based on the fully automatic error variable of the present invention samples data of a certain length on the real-time signal amplitude, performs fast Fourier transform (FFT) on it, and estimates the amplitude and phase errors to form a fully automatic error variable benchmark, which conveniently and quickly realizes the automatic calibration of the amplitude and phase errors between channels, eliminates the amplitude and phase differences between channels, ensures the accuracy of the system beam directivity, ensures that the system simulates the azimuth, distance and other related information of the target according to actual combat requirements, and realizes rapid and efficient evaluation of the receiving and transmitting channel performance of the radar.

[0018] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description and the preceding claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings, in which:

[0020] Figure 1 Detailed flow chart for automatic error variable benchmark generation;

[0021] Figure 2 This is a block diagram of the principle of multi-channel transmission and reception calibration and evaluation of phased array radar. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present invention clearer, the present invention is further described below in conjunction with the accompanying drawings. In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention.

[0023] See also Figure 1 and Figure 2 , Figure 1 This is the principle diagram of the fully automatic variable production process. Figure 2 This is the principle block diagram of the phased array radar multi-channel transmission and reception performance evaluation. Figure 2 The system includes: a DSP chip, an FPGA chip, an AD channel (including the chip), a DA channel (including the chip), a calibration channel (including the chip), and a power divider coupler (including the functions of the power divider and the coupler).

[0024] Specifically, a Field-Programmable Gate Array (FPGA) is an integrated circuit (IC) that can be reprogrammed on-site (i.e., after production) to perform specific tasks. FPGA is a highly flexible hardware platform that can implement complex digital logic and algorithms at the hardware level, and therefore has a wide range of applications in many fields.

[0025] The radio frequency multi-channel amplitude and phase calibration method based on full-automatic error variables of the present invention is used for radio frequency multi-channel amplitude and phase calibration of a phased array radar system. Fully automatic variable generation is first performed, that is, data sampling of a set length is performed on the real-time signal amplitude through multiple data acquisition channels, and then a fast Fourier transform is performed on the sampled data and amplitude and phase error estimation is performed, thereby forming a fully automatic error variable benchmark, and the error variable benchmark is stored in real time;

[0026] After selecting the calibration mode, the transmit channel calibration and the receive channel calibration are performed. First, the channel signal amplitude value and the real-time signal amplitude over a period of time are sampled for a certain length of data, and the data is fast Fourier transformed and the amplitude and phase errors are estimated to form a fully automatic error variable benchmark for horizontal comparison to obtain a difference value, forming a calibration compensation factor, and making real-time corrections to the channel amplitude calibration value. In order to further improve the accuracy of the real-time calibration compensation factor, after multiple samplings, the automatic variable generated values ​​are averaged multiple times to obtain a high-precision real-time calibration compensation factor, which can reduce the error of the calibration compensation value.

[0027] When the radar system stops working, the automatic variable generation and collection work can be carried out regularly, and the automatic error variable benchmark can be updated in real time regularly, so as to ensure the high accuracy of the calibration compensation factor. The specific process of automatic error variable benchmark generation is as follows: Figure 1 In this embodiment, 12 data acquisition channels are used to perform data sampling of a set length on the real-time signal amplitude.

[0028] The process of the phased array radar multi-channel transmission and reception performance calibration evaluation method is as follows: Figure 2 As shown, where:

[0029] The receiving channel calibration includes: the FPGA processor controls each channel to enter the receiving mode, generates a calibration signal by controlling the calibration channel, and the calibration signal enters each receiving channel through the power divider coupler;

[0030] The receiving channel sends the received intermediate frequency signal to AD for sampling, converts the analog signal into a digital signal, and completes signal processing to obtain the amplitude and phase of each channel;

[0031] Since the amplitude and phase of the calibration signal generated by the calibration channel are constant values, the amplitude and phase calibration values ​​corresponding to each channel can be calculated based on the amplitude and phase information of channels 1 to 12, and an amplitude and phase calibration table can be established. The calibration information is stored in the memory. Each subsequent time the receiving channel is calibrated, the calibration value corrected by the calibration factor is automatically read to achieve channel amplitude and phase compensation and ensure channel amplitude and phase consistency.

[0032] When the system enters the transmit calibration mode, the FPGA processor controls the first channel of the multi-channel to send out an RF signal, which enters the calibration channel through the power amplifier coupler;

[0033] The intermediate frequency signal is sampled in sequence, and the analog signal is converted into a digital signal. After corresponding processing, the amplitude and phase information of the transmitting channel are obtained. According to the above steps, the amplitude and phase information of the 1st to 12th channels are collected in sequence;

[0034] Then, the required amplitude and phase calibration values ​​are calculated based on the amplitude and phase information of all channels, and an amplitude and phase calibration table is established. At the same time, the calibration information is stored in the memory. Each time the transmit channel is calibrated, the calibration value corrected by the calibration factor is automatically read to achieve channel amplitude and phase compensation and ensure channel amplitude and phase consistency.

[0035] The RF multi-channel amplitude and phase calibration method based on the fully automatic error variable of the present invention performs fast Fourier transform (FFT) on the sampling data of the real-time signal amplitude with a set length, and estimates the amplitude and phase errors to form a fully automatic error variable benchmark, so as to conveniently and quickly realize the automatic calibration of the amplitude and phase errors between channels, eliminate the amplitude and phase differences between channels, and ensure the accuracy of the system beam directivity;

[0036] The amplitude and phase calibration tables obtained during the calibration process can also complete the evaluation function, that is, ensure that the system simulates the target's azimuth, distance and other related information in accordance with actual combat requirements, and realize fast and efficient evaluation of the radar's receiving and transmitting channel performance. It has good adaptability and flexibility; and has the ability to simulate real-life on-site targets in multiple directions and at different distances, which can realize the evaluation of radar channel receiving and transmitting performance and enhance the ability to quickly evaluate equipment performance.

[0037] It should be appreciated that embodiments of the present invention may be implemented or enforced by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer-readable memory. The method may be implemented in a computer program using standard programming techniques - including a non-transitory computer-readable storage medium configured with a computer program, wherein the storage medium so configured causes the computer to operate in a specific and predefined manner - according to the methods and drawings described in the specific embodiments. Each program may be implemented in a high-level procedural or object-oriented programming language to communicate with a computer system. However, if desired, the program may be implemented in an assembly or machine language. In any case, the language may be a compiled or interpreted language. In addition, the program may be run on a programmed ASIC for this purpose.

[0038] Furthermore, the operations of the processes described herein may be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The processes described herein (or variations and / or combinations thereof) may be performed under the control of one or more computer systems configured with executable instructions, and may be implemented as code (e.g., executable instructions, one or more computer programs, or one or more applications) that is executed collectively on one or more processors, by hardware, or a combination thereof. The computer program includes a plurality of instructions that may be executed by one or more processors.

[0039] Further, the methods may be implemented in any type of computing platform operably connected to a suitable computer, including but not limited to a personal computer, a minicomputer, a mainframe, a workstation, a network or distributed computing environment, a separate or integrated computer platform, etc. Aspects of the present invention may be implemented in machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, an optical read and / or write storage medium, a RAM, a ROM, etc., such that it can be read by a programmable computer, which when the storage medium or device is read by the computer can be used to configure and operate the computer to perform the processes described herein.

[0040] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A radio frequency multi-channel amplitude and phase calibration method based on fully automatic error variables is used for radio frequency multi-channel amplitude and phase calibration and evaluation of phased array radar systems, characterized by: The method includes fully automatic variable generation, that is, data sampling of real-time signal amplitudes through multiple data acquisition channels, fast Fourier transformation of the sampled data and amplitude and phase error estimation, thereby forming a fully automatic error variable benchmark, and storing the error variable benchmark in real time; After selecting the calibration mode, the transmitting channel calibration and the receiving channel calibration are performed. First, the channel signal amplitude value and the real-time signal amplitude over a period of time are sampled for a certain length of data, and a fast Fourier transform is performed on them and the amplitude and phase errors are estimated. A fully automatic error variable benchmark is formed for horizontal comparison to obtain a difference, which forms a calibration compensation factor and performs real-time correction on the channel amplitude calibration value.

2. The RF multi-channel amplitude and phase calibration method based on fully automatic error variables according to claim 1 is characterized in that: After multiple samplings, the automatically generated variable values ​​are averaged multiple times to obtain a high-precision real-time calibration compensation factor, which can reduce the error of the calibration compensation value.

3. The method for RF multi-channel amplitude and phase calibration based on fully automatic error variables according to claim 2 is characterized in that: The receiving channel calibration includes: controlling each channel to enter a receiving mode through a processor, controlling the calibration channel to generate a calibration signal, and the calibration signal enters each receiving channel through a power splitter coupler; The receiving channel sends the received intermediate frequency signal to AD for sampling, converts the analog signal into a digital signal, and completes signal processing to obtain the amplitude and phase of each channel; Since the amplitude and phase of the calibration signal generated by the calibration channel are constant values, the amplitude and phase calibration values ​​corresponding to each channel can be calculated based on the amplitude and phase information of each channel, and an amplitude and phase calibration table can be established. The calibration information is stored in the memory. Each time the receiving channel is calibrated thereafter, the calibration value corrected by the calibration factor is automatically read to achieve channel amplitude and phase compensation and ensure channel amplitude and phase consistency.

4. The RF multi-channel amplitude and phase calibration method based on fully automatic error variables according to claim 1 is characterized in that: The transmitting channel calibration comprises: controlling one of the multiple channels through a processor to send out a radio frequency signal, which enters the calibration channel through a power amplifier coupler; The intermediate frequency signal is sampled in sequence, and the analog signal is converted into a digital signal. After corresponding processing, the amplitude and phase information of the transmitting channel are obtained. According to the above steps, the amplitude and phase information of multiple channels are collected in sequence; Then, the required amplitude and phase calibration values ​​are calculated based on the amplitude and phase information of all channels, and an amplitude and phase calibration table is established. At the same time, the calibration information is stored in the memory. Each time the transmit channel is calibrated, the calibration value corrected by the calibration factor is automatically read to achieve channel amplitude and phase compensation and ensure channel amplitude and phase consistency.

5. The method for RF multi-channel amplitude and phase calibration based on fully automatic error variables according to claim 1, characterized in that: When the phased array radar system stops working, the fully automatic variable generation and collection work is performed by setting a timing, and the fully automatic variables are updated in real time at a regular interval to ensure the high accuracy of the calibration compensation factor.

6. The method for RF multi-channel amplitude and phase calibration based on fully automatic error variables according to claim 1, characterized in that: The amplitude and phase calibration tables obtained during the calibration process can be used to quickly evaluate the performance of the radar's receiving and transmitting channels.

Images