A Beidou anti-interference antenna and implementation method thereof

Abstract

The present invention discloses a Beidou anti-interference antenna and an implementation method thereof, the antenna comprising an array antenna, an amplifier, an analog-to-digital converter ADC, an operating mode selection circuit, an anti-interference processing circuit and a baseband signal processing circuit, wherein the array antenna, the amplifier, the analog-to-digital converter ADC, the operating mode selection circuit, the anti-interference processing circuit and the baseband signal processing circuit are connected in sequence, the array antenna receives a radio frequency signal, amplifies the signal through the amplifier, and directly performs radio frequency sampling, after the analog radio frequency signal is converted into a digital signal through the analog-to-digital converter ADC, the mixing and anti-interference processing are performed in the digital domain. The present invention can effectively broaden the use scenarios and anti-interference work efficiency of the Beidou anti-interference antenna.

Description

Technical Field

[0001] The present invention relates to the technical field of anti-interference antennas, and particularly to a Beidou anti-interference antenna and its implementation method. Background Art

[0002] With the full completion of China's Beidou-3 satellite navigation system globally, its applications are becoming increasingly widespread. Especially in the field of national defense applications, the anti-interference performance requirements for Beidou navigation devices are also getting higher and higher. Currently, most mainstream anti-interference solutions adopt space-time adaptive filtering technology, which can effectively suppress narrowband interference, broadband interference, pulse interference, swept-frequency interference, and other types of interference in the space environment. Conventional Beidou anti-interference devices generally include a receiving array antenna, a radio frequency channel, an analog-to-digital converter ADC, and anti-interference processing. Among them, the radio frequency channel generally adopts the widely used superheterodyne structure. Through frequency mixing, the radio frequency signal is transformed into an intermediate frequency for space-time adaptive signal processing.

[0003] The general processing flow of the Beidou anti-interference antenna is as Figure 2 shown. As can be seen from the figure, the radio frequency channel includes multiple stages of signal amplification and filtering, and there is also frequency mixing. The circuit is relatively complex, and there are many types of devices. Inevitably, device aging and parameter drift will occur. At the same time, the analog mixer will also bring intermodulation distortion and "image interference". When not properly processed, it will seriously affect the anti-interference performance. At the same time, the filtering and mixer parameters of this circuit architecture are fixed and can only work at a certain fixed frequency point, and the usage scenario is relatively single. Summary of the Invention

[0004] The purpose of the present invention is to provide a Beidou anti-interference antenna and its implementation method to solve the technical problem of how to broaden the usage range of the Beidou anti-interference antenna.

[0005] The present invention is implemented by the following technical solutions: A Beidou anti-interference antenna includes an array antenna, an amplifier, an analog-to-digital converter ADC, a working mode selection circuit, an anti-interference processing circuit, and a baseband signal processing circuit. Among them, the array antenna, amplifier, analog-to-digital converter ADC, working mode selection circuit, anti-interference processing circuit, and baseband signal processing circuit are connected in sequence. The array antenna receives a radio frequency signal. After the signal is amplified by the amplifier, it directly performs radio frequency sampling. After the analog radio frequency signal is converted into a digital signal by the analog-to-digital converter ADC, frequency mixing and anti-interference processing are performed in the digital domain.

[0006] Furthermore, it further includes an environmental status monitoring circuit, and the environmental status monitoring circuit is respectively connected to the analog-to-digital converter ADC and the working mode selection circuit.

[0007] Furthermore, the anti-interference processing circuit includes a B3 frequency point anti-interference processing circuit, a B1 frequency point anti-interference processing circuit and a dual-frequency direct-through circuit.

[0008] A method for implementing a Beidou anti-interference antenna comprises the following steps:

[0009] S1: Build a multi-channel broadband signal receiving device, debug each circuit, and ensure that each circuit can work normally and reliably;

[0010] S2: Receive spatial signals through a signal receiving device, where two channels pre-process signals at the B3 frequency point, and the other two channels pre-process signals at the B1 frequency point, to determine the characteristics of the anti-interference antenna environment;

[0011] S3: Determine the working mode of the Beidou anti-interference antenna and select the circuit working parameters;

[0012] S4: Perform adaptive processing of array signals to suppress broadband interference signals;

[0013] S5: Send the processed signal to the baseband to complete the positioning solution.

[0014] Furthermore, step S2 includes the following sub-steps:

[0015] S21: After receiving the spatial signal, first determine the environmental characteristics of the anti-interference antenna, analyze the signal characteristics at the B3 frequency point for the data of channels 1 and 2, and determine whether there is an interference signal;

[0016] S22: Analyze the signal characteristics at the B1 frequency point for the data of channels 3 and 4 to determine whether there is an interference signal.

[0017] Furthermore, step S21 includes the following sub-steps:

[0018] S211: Perform digital down-conversion on the data of channel 1 and channel 2, and convert the RF signal into a digital intermediate frequency;

[0019] S212: Estimating the power strength and spectrum of the digital intermediate frequency signal to determine whether there is an interference signal in the environment;

[0020] S213: If an interference signal exists, an interference signal flag is given.

[0021] Further, step S22 includes the following sub-steps:

[0022] S221: Perform digital down-conversion on the data of channel 3 and channel 4, and convert the RF signal into a digital intermediate frequency;

[0023] S222: Estimating the power strength and spectrum of the digital intermediate frequency signal to determine whether there is an interference signal in the environment;

[0024] S223: If an interference signal exists, an interference signal flag is given.

[0025] Further, step S3 is specifically as follows: according to the anti-interference antenna environment characteristics in step S2, determining the working mode of the Beidou anti-interference antenna, wherein the anti-interference antenna environment characteristics include whether there are interference signals of B3 frequency points and B1 frequency points in the anti-interference antenna environment.

[0026] Furthermore, if there are no interference signals at both the B3 frequency point and the B1 frequency point in the anti-interference antenna environment, the anti-interference antenna operates in a dual-frequency direct link mode and does not perform anti-interference signal processing; if there are interference signals at both the B3 frequency point and the B1 frequency point in the anti-interference antenna environment, it is necessary to determine the strength of the interference signals at the B3 frequency point and the B1 frequency point, and the anti-interference antenna operates at a frequency point where the interference signal is weak.

[0027] Furthermore, if there is no B3 frequency interference signal in the anti-interference antenna environment, but there is a B1 frequency interference signal, the anti-interference antenna operates at the B3 frequency; if there is a B3 frequency interference signal in the anti-interference antenna environment, but there is no B1 frequency interference signal, the anti-interference antenna operates at the B1 frequency.

[0028] The beneficial effects of the present invention are as follows: the present invention utilizes radio frequency direct sampling technology, which can effectively reduce the complexity of hardware circuits and improve the reliability of Beidou anti-interference antennas; and according to environmental characteristics, through flexible configuration, the Beidou anti-interference antenna can operate at different frequencies, which can effectively broaden the use scenarios and anti-interference work efficiency of the Beidou anti-interference antenna and achieve optimal anti-interference performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0030] Figure 1 It is a schematic diagram of the structure of the present invention;

[0031] Figure 2 It is a schematic diagram of the structure of the existing anti-interference antenna;

[0032] Figure 3 Flowchart for determining the characteristics of the anti-interference antenna environment. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0034] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0035] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0036] Example 1

[0037] See also Figure 1 , a Beidou anti-interference antenna, including an array antenna, a low noise amplifier, an analog-to-digital converter ADC, a working mode selection circuit, an anti-interference processing circuit and a baseband signal processing circuit, wherein the array antenna, the low noise amplifier, the analog-to-digital converter ADC, the working mode selection circuit, the anti-interference processing circuit and the baseband signal processing circuit are connected in sequence, and also includes an environmental state monitoring circuit, the environmental state monitoring circuit is respectively connected to the analog-to-digital converter ADC and the working mode selection circuit, the array antenna receives the radio frequency signal, amplifies the signal through the low noise amplifier, and directly performs radio frequency sampling, after the analog radio frequency signal is converted into a digital signal through the analog-to-digital converter ADC, the mixing and anti-interference processing are performed in the digital domain. Such a design not only simplifies the hardware circuit of the radio frequency channel and improves the reliability and stability of the anti-interference antenna, but also realizes the miniaturization of the anti-interference antenna and the diversification of the working frequency, which can effectively broaden the use scenarios and anti-interference work efficiency of the Beidou anti-interference antenna.

[0038] In this embodiment, the anti-interference processing circuit includes a B3 frequency (1.2GHz) anti-interference processing circuit, a B1 frequency (1.5GHz) anti-interference processing circuit and a dual-frequency direct circuit. The present invention can realize B3 frequency or B1 frequency airspace anti-interference processing. The current mainstream satellite positioning frequency is concentrated near 1.2GHz (B3 frequency) and 1.5GHz (B1 frequency). According to the Nyquist sampling theorem, the rate of the RF direct sampling of the present invention should be above 3GHz. In order to achieve relatively high anti-interference performance, the analog-to-digital converter ADC should select a chip with more than 12 bits, and the baseband signal processing should select a high-performance FPGA. Due to the direct RF sampling, the sampling rate is above 3GHz, the amount of data is very large, and it is particularly important for the subsequent data processing method. The bandwidth of the navigation signal generally varies from a few MHz to several MHz. Before the anti-interference processing, down-conversion processing and data downsampling processing must be performed to reduce the amount of data processing. According to the actual situation of the use environment, the present invention has the ability to automatically configure the working frequency and adopts an array antenna (such as 4 elements) to receive spatial signals. The low-noise amplifier should include two frequencies of 1.2 GHz and 1.5 GHz. The characteristics of the anti-interference antenna environment are determined first, and then the working frequency is configured.

[0039] A method for implementing a Beidou anti-interference antenna comprises the following steps:

[0040] S1: Build a multi-channel broadband signal receiving device, debug each circuit, and ensure that each circuit can work normally and reliably;

[0041] S2: Receive spatial signals through a signal receiving device, where two channels pre-process signals at the B3 frequency point, and the other two channels pre-process signals at the B1 frequency point, to determine the characteristics of the anti-interference antenna environment;

[0042] S3: Determine the working mode of the Beidou anti-interference antenna and select the circuit working parameters;

[0043] S4: Perform adaptive processing of array signals to suppress broadband interference signals;

[0044] S5: Send the processed signal to the baseband to complete the positioning solution.

[0045] See Figure 3 , step S2 includes the following sub-steps:

[0046] S21: After receiving the spatial signal, first determine the environmental characteristics of the anti-interference antenna, analyze the signal characteristics at 1.2 GHz for the data of channels 1 and 2, and determine whether there is an interference signal;

[0047] S22: Analyze the signal characteristics at 1.5 GHz for the data of channels 3 and 4 to determine whether there is an interference signal.

[0048] In this embodiment, step S21 includes the following sub-steps:

[0049] S211: digitally down-convert the data of channel 1 and channel 2, and convert the RF signal at 1268.52 MHz to a digital intermediate frequency (19.48 MHz);

[0050] S212: Estimating the power strength and spectrum of the digital intermediate frequency signal to determine whether there is an interference signal in the environment;

[0051] S213: If an interference signal exists, an interference signal flag is given.

[0052] In this embodiment, step S22 includes the following sub-steps:

[0053] S221: Perform digital down-conversion on the data of channels 3 and 4, and convert the RF signal at 1561.098 MHz to a digital intermediate frequency (16.098 MHz);

[0054] S222: Estimating the power strength and spectrum of the digital intermediate frequency signal to determine whether there is an interference signal in the environment;

[0055] S223: If an interference signal exists, an interference signal flag is given.

[0056] In this embodiment, step S3 includes the following sub-steps:

[0057] S31: Determine the working mode of the Beidou anti-interference antenna according to whether there is an interference signal mark in the anti-interference antenna environment given in step S2;

[0058] S32: If there is no interference signal of B3 and B1 frequencies in the environment, the anti-interference antenna works in the dual-frequency direct link mode, and no anti-interference signal processing is performed. Channel 1 and channel 3 work at B3 and B1 frequencies respectively, while channels 2 and 4 are closed, and the signals of these two frequencies are sent to the baseband, so that the receiver works in the dual-frequency positioning mode, which not only reduces the power consumption of the whole machine, but also improves the positioning accuracy.

[0059] S33: If there is no B3 frequency interference signal in the environment, but there is a B1 frequency interference signal, then the anti-interference antenna works at the B3 frequency.

[0060] S34: If there is a B3 frequency interference signal in the environment, but no B1 frequency interference signal, then the anti-interference antenna works at the B1 frequency.

[0061] S35: If there are interference signals at both the B3 and B1 frequencies in the environment, this determines which frequency has a stronger interference signal. If the B3 frequency has a stronger interference signal, the anti-interference antenna works at the B1 frequency, and vice versa.

[0062] To further illustrate the working process of the present application: after the spatial signal is received by the array antenna, the signals at 1.2 GHz and 1.5 GHz are preprocessed respectively, and the anti-interference antenna environment characteristics are determined by power and spectrum estimation. If there are no B3 and B1 interference signals in the environment, the anti-interference antenna works in the dual-frequency direct link mode, and no anti-interference signal processing is performed. The 1st and 3rd channels work at the B3 and B1 frequencies respectively, and the 2nd and 4th channels are closed at the same time, and the signals of these two frequencies are sent to the baseband, so that the receiver works in the dual-frequency positioning mode, which not only reduces the power consumption of the whole machine, but also improves the positioning accuracy. If there is no B3 interference signal in the environment, but there is a B1 interference signal, then the anti-interference antenna works at the B3 frequency at this time; if there is a B3 interference signal in the environment, but no B1 interference signal, then the anti-interference antenna works at the B1 frequency at this time; if there are both B3 and B1 interference signals in the environment, it is determined which frequency has a stronger interference signal. If the B3 interference signal is strong, the anti-interference antenna works at the B1 frequency, and vice versa.

[0063] The present invention has at least the following technical effects:

[0064] The present invention utilizes radio frequency direct sampling technology, which can effectively reduce the complexity of hardware circuits and improve the reliability of Beidou anti-interference antennas; and according to environmental characteristics, through flexible configuration, the Beidou anti-interference antenna can operate at different frequencies, which can effectively broaden the use scenarios and anti-interference work efficiency of the Beidou anti-interference antenna and achieve optimal anti-interference performance.

[0065] It should be noted that, for the above embodiments, for the sake of simplicity, they are all described as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the order of the actions described, because according to the present application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification belong to preferred embodiments, and the actions involved are not necessarily required by the present application.

[0066] The above embodiments describe the basic principles and main features of the present invention and the advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by 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 changes and modifications made by those skilled in the art shall be within the scope of protection of the appended claims of the present invention without departing from the spirit and scope of the present invention.

Claims

1. A Beidou anti-interference antenna, It is characterized in that It includes an array antenna, an amplifier, an analog-to-digital converter ADC, a working mode selection circuit, an anti-interference processing circuit and a baseband signal processing circuit, wherein the array antenna, the amplifier, the analog-to-digital converter ADC, the working mode selection circuit, the anti-interference processing circuit and the baseband signal processing circuit are connected in sequence, the array antenna receives a radio frequency signal, amplifies the signal through the amplifier, and then directly performs radio frequency sampling, after the analog radio frequency signal is converted into a digital signal through the analog-to-digital converter ADC, mixing and anti-interference processing are performed in the digital domain; It also includes an environmental state monitoring circuit, which is connected to the analog-to-digital converter ADC and the working mode selection circuit respectively; The anti-interference processing circuit includes a B3 frequency point anti-interference processing circuit, a B1 frequency point anti-interference processing circuit and a dual-frequency direct-through circuit.

2. A method for implementing a Beidou anti-interference antenna, used to implement the Beidou anti-interference antenna described in claim 1, It is characterized in that The steps include: S1: Build a multi-channel broadband signal receiving device, debug each circuit, and ensure that each circuit can work normally and reliably; S2: Receive spatial signals through a signal receiving device, where two channels pre-process signals at the B3 frequency point, and the other two channels pre-process signals at the B1 frequency point, to determine the characteristics of the anti-interference antenna environment; S3: Determine the working mode of the Beidou anti-interference antenna and select the circuit working parameters; S4: Perform adaptive processing of array signals to suppress broadband interference signals; S5: Send the processed signal to the baseband to complete the positioning solution.

3. A method for implementing a Beidou anti-interference antenna as claimed in claim 2, It is characterized in that Step S2 includes the following sub-steps: S21: After receiving the spatial signal, first determine the environmental characteristics of the anti-interference antenna, analyze the signal characteristics at the B3 frequency point for the data of channels 1 and 2, and determine whether there is an interference signal; S22: Analyze the signal characteristics at the B1 frequency point for the data of channels 3 and 4 to determine whether there is an interference signal.

4. A method for implementing a Beidou anti-interference antenna as claimed in claim 3, It is characterized in that Step S21 includes the following sub-steps: S211: Perform digital down-conversion on the data of channel 1 and channel 2, and convert the RF signal into a digital intermediate frequency; S212: Estimating the power strength and spectrum of the digital intermediate frequency signal to determine whether there is an interference signal in the environment; S213: If an interference signal exists, an interference signal flag is given.

5. A method for implementing a Beidou anti-interference antenna as claimed in claim 3, It is characterized in that Step S22 includes the following sub-steps: S221: Perform digital down-conversion on the data of channel 3 and channel 4, and convert the RF signal into a digital intermediate frequency; S222: Estimating the power strength and spectrum of the digital intermediate frequency signal to determine whether there is an interference signal in the environment; S223: If an interference signal exists, an interference signal flag is given.

6. A method for implementing a Beidou anti-interference antenna as claimed in claim 2, It is characterized in that Step S3 is specifically: determining the working mode of the Beidou anti-interference antenna according to the anti-interference antenna environment characteristics in step S2, wherein the anti-interference antenna environment characteristics include whether there are interference signals of B3 frequency points and B1 frequency points in the anti-interference antenna environment.

7. A method for implementing a Beidou anti-interference antenna as claimed in claim 6, It is characterized in that If there are no interference signals at both the B3 and B1 frequencies in the anti-interference antenna environment, the anti-interference antenna operates in the dual-frequency direct link mode without performing anti-interference signal processing; If there are interference signals at both the B3 and B1 frequencies in the anti-interference antenna environment, it is necessary to determine the strength of the interference signals at the B3 and B1 frequencies, and the anti-interference antenna operates at the frequency where the interference signal is weak.

8. A method for implementing a Beidou anti-interference antenna as claimed in claim 6, It is characterized in that If there is no B3 frequency interference signal in the anti-interference antenna environment, but there is a B1 frequency interference signal, the anti-interference antenna operates at the B3 frequency; if there is a B3 frequency interference signal in the anti-interference antenna environment, but there is no B1 frequency interference signal, the anti-interference antenna operates at the B1 frequency.

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