CN114167454A - Satellite navigation anti-interference antenna channel amplitude-phase consistency calibration system and method - Google Patents
Satellite navigation anti-interference antenna channel amplitude-phase consistency calibration system and method Download PDFInfo
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- CN114167454A CN114167454A CN202111336674.5A CN202111336674A CN114167454A CN 114167454 A CN114167454 A CN 114167454A CN 202111336674 A CN202111336674 A CN 202111336674A CN 114167454 A CN114167454 A CN 114167454A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/13—Receivers
- G01S19/21—Interference related issues ; Issues related to cross-correlation, spoofing or other methods of denial of service
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/13—Receivers
- G01S19/20—Integrity monitoring, fault detection or fault isolation of space segment
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/13—Receivers
- G01S19/23—Testing, monitoring, correcting or calibrating of receiver elements
- G01S19/235—Calibration of receiver components
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- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Computer Security & Cryptography (AREA)
- Variable-Direction Aerials And Aerial Arrays (AREA)
Abstract
The invention discloses a system and a method for calibrating amplitude-phase consistency of channels of an anti-interference antenna for satellite navigation, which utilize FPGA to generate calibration signals, convert the calibration signals into analog signals through a D/A conversion circuit, up-convert the analog signals into radio frequency signals through an up-converter, inject the radio frequency signals into radio frequency input ends of channels of down-converters of each path, make difference between each path of signals and a reference path at a baseband, adjust the amplitude and phase values of each path of signals through a self-adaptive filtering algorithm, minimize the difference value between each channel and the reference path, and further obtain the amplitude and phase correction value of each path of signals. The invention utilizes the existing hardware resources of the satellite navigation anti-interference antenna, has small software and hardware change and good implementation effect, solves the problems of the traditional anti-interference antenna such as high radio frequency design difficulty and reduced anti-interference capability caused by poor channel amplitude consistency, shortens the hardware debugging time, improves the working efficiency and reduces the system cost.
Description
Technical Field
The invention relates to the technical field of satellite navigation, in particular to a system and a method for calibrating amplitude-phase consistency of an anti-interference antenna channel of satellite navigation.
Background
Because the satellite navigation signal intensity is weak, and the working frequency band is fixed and open, the system performance is reduced or even loses efficacy easily due to interference, and an anti-interference antenna is mostly adopted to improve the anti-interference capability of the satellite navigation receiver on occasions with higher reliability requirements. The common anti-interference antenna usually adopts an array processing method to eliminate interference, the influence of the consistency of the amplitude and phase of each channel on the anti-interference processing effect of the rear end is very important, and the anti-interference capability of the algorithm is obviously reduced due to the poor consistency of the amplitude and phase of the channel. In order to deal with the influence of poor channel amplitude-phase consistency on interference resistance, a higher amplitude-phase consistency requirement is usually provided for the radio frequency module, which increases the difficulty in developing the radio frequency module. Even if the radio frequency module strictly controls the amplitude-phase consistency of each channel through a complex design, the existing technology and process still cause some differences in the amplitude-phase consistency of each channel, and the residual amplitude-phase error of the radio frequency module also causes the reduction of the anti-interference capability of the system.
Disclosure of Invention
The invention aims to overcome the existing defects and provides a system and a method for calibrating the amplitude-phase consistency of a satellite navigation anti-interference antenna channel, which solve the problems of the traditional anti-interference antenna that the radio frequency design difficulty is high, the anti-interference capability is reduced due to the poor amplitude-phase consistency of the channel, shorten the hardware debugging time, improve the working efficiency, reduce the system cost and effectively solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme: a satellite navigation anti-interference antenna channel amplitude-phase consistency calibration system comprises an antenna array, a radio frequency module and a signal processing module, wherein the antenna array, the radio frequency module and the signal processing module are sequentially connected; the radio frequency module comprises a plurality of down converters and an up converter, and the up converter is connected with the down converters through a power divider; the signal processing module comprises an A/D sampling circuit, a digital signal processing circuit and a D/A conversion circuit, wherein the digital signal processing circuit takes an FPGA as a core processor.
Preferably, the antenna array comprises antenna units corresponding to the down converters one by one, and the distance between two adjacent antenna units is less than 1/2 wavelengths.
Preferably, radio frequency switches are correspondingly arranged between the power divider and the down converters.
Preferably, the a/D sampling circuits are provided in plurality and correspond to the down converters one by one.
A satellite navigation anti-interference antenna channel amplitude-phase consistency calibration method comprises the following steps:
s1: a plurality of antenna units of the antenna array receive space satellite signals and interference signals, and the signals of each antenna unit are transmitted to a corresponding down converter;
s2: the down converter processes signals of corresponding antenna units, carries out filtering, amplification and frequency mixing processing on the received signals, converts the signals to baseband signals suitable for corresponding A/D sampling circuits, and the A/D sampling circuits convert the baseband signals into digital signals and then send the digital signals to the digital signal processing circuit;
s3: the FPGA in the digital signal processing circuit processes a digital signal to generate a signal source, and then outputs a path of analog signal through a D/A conversion circuit, the path of analog signal is up-converted into a radio frequency signal through an up-converter, the radio frequency signal is a reference signal, the FPGA controls a corresponding radio frequency switch to be opened, and then a power divider divides the reference signal into multiple paths to be input to a plurality of down converters;
s4: the FPGA in the digital signal processing circuit makes a difference between each received signal and a reference signal in a baseband, the amplitude and phase value of each signal are adjusted through a self-adaptive filtering algorithm to minimize the difference value, so that the amplitude and phase correction value of each signal is obtained, the correction value is stored in an RAM in the FPGA for subsequent anti-interference calculation, then correction data output is cut off, and the corresponding radio frequency switch is controlled to be closed;
s5: and compensating the amplitude-phase consistency of each channel by using the correction value, sending the channel into a digital signal processing circuit for anti-interference processing, mixing data subjected to anti-interference processing to generate a path of intermediate frequency signal, outputting an analog intermediate frequency signal through a D/A conversion circuit, and sending the analog intermediate frequency signal into an up-converter for processing and outputting.
Compared with the prior art, the invention has the beneficial effects that: the system for calibrating the amplitude-phase consistency of the satellite navigation anti-interference antenna channel slightly changes the software and hardware resources of the existing anti-interference antenna, utilizes an FPGA to generate a signal source, converts the signal source into an analog signal through a D/A conversion circuit, then up-converts the analog signal into a radio frequency signal, injects the radio frequency signal into the radio frequency input end of each channel of down-conversion channel, differentiates each channel of signal from a reference channel at a baseband, adjusts the amplitude and phase value of each channel of signal through a self-adaptive filtering algorithm to minimize the differential value, thereby obtaining the amplitude and phase correction value of each channel of signal, and utilizes the correction value to compensate the amplitude-phase consistency of each channel and then sends the amplitude-phase consistency of each channel into a digital signal processing circuit for anti-interference processing; the existing hardware resources of the satellite navigation anti-interference antenna are utilized, the software and hardware change is small, the implementation effect is good, and the anti-interference capability of the system is improved; the development difficulty of the radio frequency module is greatly reduced, the hardware debugging time is shortened, the working efficiency is improved, and the system cost is reduced.
Drawings
FIG. 1 is a schematic view of the structure of the present invention.
In the figure: the system comprises an antenna array 1, an antenna unit 1.1, a radio frequency module 2, a down converter 2.1, an up converter 2.2, a power divider 2.3, a radio frequency switch 2.4, a signal processing module 3, an A/D sampling circuit 3.1, a digital signal processing circuit 3.2 and a D/A conversion circuit 3.3.
Detailed Description
In the following description, the technical solutions of the present invention will be described with reference to the drawings of the embodiments of the present invention, and it should be understood that, if there is an orientation or positional relationship indicated by terms such as "upper", "lower", "front", "rear", "left", "right", etc., it is only corresponding to the drawings of the present invention, and for convenience of describing the present invention, it is not necessary to indicate or imply that the indicated devices or elements have a specific orientation:
referring to fig. 1, the present invention provides a technical solution: a satellite navigation anti-interference antenna channel amplitude-phase consistency calibration system comprises an antenna array 1, a radio frequency module 2 and a signal processing module 3, wherein the antenna array 1, the radio frequency module 2 and the signal processing module 3 are sequentially connected; the radio frequency module 2 comprises a plurality of down converters 2.1 and an up converter 2.2, and the up converter 2.2 is connected with the plurality of down converters 2.1 through a power divider 2.3; the signal processing module 3 comprises an A/D sampling circuit 3.1, a digital signal processing circuit 3.2 and a D/A conversion circuit 3.3, and the digital signal processing circuit 3.2 takes an FPGA as a core processor; radio frequency switches 2.4 are correspondingly arranged between the power divider 2.3 and the down converters 2.1; a plurality of A/D sampling circuits 3.1 are arranged and correspond to the plurality of down converters 2.1 one by one; compared with the traditional anti-interference antenna, the multi-path power divider 2.3 is only added to the output of the up-converter 2.2 of the radio frequency module 2, the radio frequency switch 2.4 is added between the power divider 2.3 and the input of each down-conversion channel, and the output of the up-conversion channel is connected with the input of each down-conversion channel;
the antenna array 1 comprises antenna units 1.1 which are in one-to-one correspondence with a plurality of down converters 2.1, and the distance between two adjacent antenna units 1.1 is less than 1/2 wavelengths; when the distance between the antenna units 1.1 is greater than or equal to 1/2 wavelengths, the problem of binary ambiguity of signal direction of arrival estimation exists, redundant null is generated during anti-interference processing, and normal signal receiving is possibly influenced, so that the design of less than 1/2 wavelengths is adopted;
taking an anti-interference antenna with M array elements as an example, the antenna array 1 is composed of M antenna units 1.1 and used for receiving space satellite signals and interference signals, the radio frequency module 2 comprises M down-conversion channels and one up-conversion channel, the M down-conversion channels respectively carry out filtering, amplification and frequency mixing processing on the signals received from the antenna, the signals are converted to baseband signals suitable for being sampled by the A/D sampling circuit 3.1, the one up-conversion channel is used for up-converting the baseband signals after the anti-interference processing back to radio frequency for a rear-end receiver to use, the signal processing module 3 mainly has the function of executing an anti-interference algorithm and eliminating the interference, and the anti-interference processing algorithm is realized by a multi-purpose FPGA.
A satellite navigation anti-interference antenna channel amplitude-phase consistency calibration method comprises the following steps:
s1: a plurality of antenna units 1.1 of an antenna array 1 receive space satellite signals and interference signals, and the signals of each antenna unit 1.1 are transmitted to a corresponding down converter 2.1;
s2: the down converter 2.1 processes the signal of the corresponding antenna unit 1.1, the received signal is filtered, amplified and mixed, the signal is converted to the baseband signal suitable for the corresponding A/D sampling circuit 3.1, the A/D sampling circuit 3.1 converts the baseband signal into a digital signal and then sends the digital signal to the digital signal processing circuit 3.2;
s3: the FPGA in the digital signal processing circuit 3.2 processes the digital signal to generate a signal source, and then outputs a path of analog signal through a D/A conversion circuit 3.3, the path of analog signal is up-converted into a radio frequency signal through an up-converter 2.2, the radio frequency signal is a reference signal, the FPGA controls a corresponding radio frequency switch 2.4 to be opened, and then a power divider 2.3 divides the reference signal into multiple paths to be input to a plurality of down-converters 2.1;
s4: the FPGA in the digital signal processing circuit 3.2 makes a difference between each received signal and a reference signal at a baseband, adjusts the amplitude and phase value of each signal through a self-adaptive filtering algorithm to minimize the difference value, so as to obtain the amplitude and phase correction value of each signal, stores the correction value in an RAM in the FPGA for subsequent anti-interference calculation, then cuts off the output of the correction data, and controls the corresponding radio frequency switch 2.4 to be closed;
s5: the correction value is used for compensating the amplitude-phase consistency of each channel, the channel is sent to the digital signal processing circuit 3.2 for anti-interference processing, the data after anti-interference processing is mixed, one path of intermediate frequency signal is generated, the intermediate frequency signal is output to an analog intermediate frequency signal through the D/A conversion circuit 3.3, and then the analog intermediate frequency signal is sent to the up converter 2.2 for processing and output.
The invention adds a small amount of programs in an FPGA in a digital signal processing circuit 3.2 to generate a group of Gold codes similar to satellite signals, the Gold codes are converted into spread spectrum signals and then stored in an RAM of the FPGA, when channel calibration is needed, the FPGA controls the RAM to output data to a D/A conversion circuit 3.3 and controls a radio frequency switch 2.4 to be switched to an upper frequency conversion channel, the D/A conversion circuit 3.3 converts the signals into analog signals and sends the analog signals to the input of each channel of down frequency conversion through the upper frequency conversion channel, then the FPGA differentiates each channel of signals from a reference channel in a baseband, adjusts the amplitude and phase value of each channel of signals through a self-adaptive filtering algorithm to minimize the difference value, thereby obtaining the amplitude and phase correction value of each channel of signals, storing the correction value in the internal RAM, then cutting off the output of correction data, controlling the radio frequency switch to be switched to each antenna for receiving, compensating the amplitude-phase consistency of each channel by using the correction value and then sending the correction value to an anti-interference processing module for anti-interference processing, data after anti-interference processing are mixed, one path of intermediate frequency signal is generated, is converted into an analog intermediate frequency signal through a D/A conversion circuit 3.3 and is sent into an up-converter to be processed by the up-converter 2.2 and output, channel amplitude-phase consistency and anti-interference capacity are improved, the problems that the anti-interference capacity is reduced due to the fact that the traditional anti-interference antenna is large in radio frequency design difficulty and poor in channel amplitude-phase consistency and the like are solved, hardware debugging time is shortened, and working efficiency is improved.
In addition, when the method is used for channel calibration, the channel calibration is usually carried out when the method is started, and the method can also be used for carrying out secondary calibration on amplitude-phase change of a radio frequency channel caused by the influence of factors such as temperature after working for a period of time, wherein the time spent in one-time calibration is millisecond level, and because Gold codes have good autocorrelation and cross-correlation characteristics, the obtained calibration data has high accuracy, which is higher by one order of magnitude than the traditional method for controlling the consistency of the channel through radio frequency, and the modified part of hardware can also be used for detecting the integrity of the radio frequency channel by the calibration channel, so that the self-detection depth of an anti-interference antenna is increased.
The invention is not described in detail in the prior art, and it is apparent to a person skilled in the art that the invention is not limited to details of the above-described exemplary embodiments, but that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof; the present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein, and any reference signs in the claims are not intended to be construed as limiting the scope of the claims concerned.
Claims (5)
1. The utility model provides a satellite navigation anti-interference antenna channel amplitude and phase uniformity calbiration system which characterized in that: the antenna array comprises an antenna array (1), a radio frequency module (2) and a signal processing module (3), wherein the antenna array (1), the radio frequency module (2) and the signal processing module (3) are sequentially connected; the radio frequency module (2) comprises a plurality of down converters (2.1) and an up converter (2.2), and the up converter (2.2) is connected with the down converters (2.1) through a power divider (2.3); the signal processing module (3) comprises an A/D sampling circuit (3.1), a digital signal processing circuit (3.2) and a D/A conversion circuit (3.3), and the digital signal processing circuit (3.2) takes an FPGA as a core processor.
2. The system according to claim 1, wherein the calibration system for the amplitude-phase consistency of the satellite navigation anti-interference antenna channel comprises: the antenna array (1) comprises antenna units (1.1) which correspond to the down converters (2.1) one by one, and the distance between every two adjacent antenna units (1.1) is smaller than 1/2 wavelengths.
3. The system according to claim 1, wherein the calibration system for the amplitude-phase consistency of the satellite navigation anti-interference antenna channel comprises: radio frequency switches (2.4) are correspondingly arranged between the power divider (2.3) and the down converters (2.1).
4. The system according to claim 1, wherein the calibration system for the amplitude-phase consistency of the satellite navigation anti-interference antenna channel comprises: the A/D sampling circuits (3.1) are provided in plurality and correspond to the down converters (2.1) one by one.
5. The method for calibrating the amplitude-phase consistency of the satellite navigation anti-interference antenna channel according to claim 1, characterized by comprising the following steps:
s1: a plurality of antenna units (1.1) of an antenna array (1) receive space satellite signals and interference signals, and signals of each antenna unit (1.1) are transmitted to a corresponding down converter (2.1);
s2: the down converter (2.1) processes the signal of the corresponding antenna unit (1.1), the received signal is filtered, amplified and mixed, the signal is converted to a baseband signal suitable for the corresponding A/D sampling circuit (3.1), and the A/D sampling circuit (3.1) converts the baseband signal into a digital signal and then sends the digital signal to the digital signal processing circuit (3.2);
s3: an FPGA in a digital signal processing circuit (3.2) processes a digital signal to generate a signal source, then a D/A conversion circuit (3.3) outputs a path of analog signal, the analog signal is up-converted into a radio frequency signal through an up-converter (2.2), the radio frequency signal is a reference signal, the FPGA controls a corresponding radio frequency switch (2.4) to be opened, and then a power divider (2.3) divides the reference signal into multiple paths to be input to a plurality of down converters (2.1);
s4: the FPGA in the digital signal processing circuit (3.2) makes a difference between each received signal and a reference signal at a baseband, the amplitude and phase value of each signal are adjusted through a self-adaptive filtering algorithm to enable the difference value to be minimum, so that the amplitude and phase correction value of each signal is obtained, the correction value is stored in an RAM in the FPGA for subsequent anti-interference calculation, then correction data output is cut off, and a corresponding radio frequency switch (2.4) is controlled to be closed;
s5: and compensating the amplitude-phase consistency of each channel by using a correction value, sending the channel into a digital signal processing circuit (3.2) for anti-interference processing, mixing data subjected to anti-interference processing to generate a path of intermediate frequency signal, outputting an analog intermediate frequency signal through a D/A conversion circuit (3.3), and sending the analog intermediate frequency signal into an up-converter (2.2) for processing and outputting.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117452442A (en) * | 2023-12-21 | 2024-01-26 | 中国人民解放军国防科技大学 | High-precision satellite navigation anti-interference method based on space-frequency self-adaptive processing |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117452442A (en) * | 2023-12-21 | 2024-01-26 | 中国人民解放军国防科技大学 | High-precision satellite navigation anti-interference method based on space-frequency self-adaptive processing |
| CN117452442B (en) * | 2023-12-21 | 2024-04-05 | 中国人民解放军国防科技大学 | High-precision satellite navigation anti-interference method based on space-frequency self-adaptive processing |
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