Satellite signal interference mitigation method, satellite positioning system and receiver

Abstract

This disclosure provides a satellite signal interference suppression method, a satellite positioning system, and a receiver, relating to the field of satellite positioning technology. The method includes: the receiver acquiring a target signal via a first antenna and a second antenna, the target signal including a first signal received via the first antenna and a second signal received via the second antenna; parsing the target signal to obtain phase difference information between the first signal and the second signal, the phase difference information being used to characterize the phase difference formed when the first signal reaches the first antenna and the second signal reaches the second antenna; determining whether the receiver has received an interference signal based on the phase difference information; and, if it is determined that the receiver has received an interference signal, suppressing the interference signal based on the phase difference information. This allows for efficient and accurate determination of the existence of interference signals and suppression of interference, thereby reducing the impact of interference signals on normal satellite signals and improving the robustness of satellite navigation and positioning.

Description

Technical Field

[0001] This disclosure relates to the field of satellite positioning technology, and more specifically, to a satellite signal interference suppression method, a satellite positioning system, and a receiver. Background Technology

[0002] With the development of satellite navigation and positioning technology, satellite positioning systems are being used more and more widely, providing receivers with high-precision positioning results. However, due to the openness and fragility of satellite signals, as well as the complexity of the application environment for satellite navigation and positioning, various interference signals can occur in complex environments, leading to positioning failures or errors in the receiver, thus affecting the robustness of satellite navigation and positioning.

[0003] Therefore, how to efficiently and accurately deal with the impact of interference signals and improve the robustness of satellite navigation and positioning has become an urgent technical problem to be solved. Summary of the Invention

[0004] In view of this, the present disclosure proposes a new technical solution for suppressing satellite signal interference.

[0005] According to a first aspect of the present disclosure, a satellite signal interference suppression method is provided, applied to a receiver, the receiver including a first antenna and a second antenna; the method includes: Acquire a target signal; wherein the target signal includes a first signal received based on the first antenna and a second signal received based on the second antenna; The target signal is analyzed to obtain the phase difference information between the first signal and the second signal; wherein, the phase difference information is used to characterize the phase difference formed when the first signal arrives at the first antenna and the second signal arrives at the second antenna; Based on the phase difference information, determine whether the receiver receives an interference signal; If it is determined that the receiver has received an interference signal, interference suppression is performed on the interference signal based on the phase difference information.

[0006] Optionally, the receiver further includes a first channel and a second channel, the first channel being connected to the first antenna and the second channel being connected to the second antenna; parsing the target signal to obtain phase difference information between the first signal and the second signal includes: The phase difference information is obtained by tracking and analyzing the first signal and the second signal based on the first channel and the second channel, respectively.

[0007] Optionally, the phase difference information is obtained by tracking and analyzing the first signal and the second signal based on the first channel and the second channel, respectively, including: Based on the first channel, the first signal is tracked and analyzed to generate target loop parameters for analyzing the first signal; The second channel uses the same target loop parameters as the first channel to track and analyze the second signal, thereby obtaining the phase difference information.

[0008] Optionally, the step of tracking and analyzing the first signal based on the first channel and tracking and analyzing the second signal based on the second channel to obtain the phase difference information includes: Based on the first channel, the first signal is tracked and analyzed to obtain the first phase corresponding to the first signal; Based on the second channel, the second signal is tracked and analyzed to obtain the second phase corresponding to the second signal; The phase difference information is determined based on the first phase and the second phase.

[0009] Optionally, the target signal is one or more groups, and each group of target signals includes a first signal and a second signal carrying the same target satellite identifier; the phase difference information corresponding to each group of target signals is the phase difference formed when the first signal and the second signal carrying the same target satellite identifier are received by the first antenna and the second antenna, respectively.

[0010] Optionally, determining whether the receiver receives an interference signal based on the phase difference information includes: Obtain the antenna position information of the first antenna and the second antenna; Obtain the satellite position information of the target satellite corresponding to the target satellite identifier; Based on the satellite position information and the antenna position information, determine the first theoretical phase difference range corresponding to the target satellite identifier; If the phase difference information is outside the first theoretical phase difference range, then it is determined that the receiver has received the interference signal.

[0011] Optionally, the target signal includes a first set of target signals carrying a first satellite identifier and a second set of target signals carrying a second satellite identifier, wherein the azimuth difference between the first satellite azimuth corresponding to the first satellite identifier and the second satellite azimuth corresponding to the second satellite identifier is greater than or equal to a preset azimuth difference threshold; the phase difference information includes a first phase difference corresponding to the first set of target signals and a second phase difference corresponding to the second set of target signals. Determining whether the receiver receives an interference signal based on the phase difference information includes: If the difference between the first phase difference and the second phase difference is less than or equal to a preset phase difference threshold, then it is determined that the receiver has received the interference signal.

[0012] Optionally, the interference suppression based on the phase difference information includes: The filtering weights of the first antenna and the second antenna are determined based on the phase difference information; Based on the filtering weights, the signals received from the first antenna and the second antenna are filtered to suppress the direction of arrival of the interference signals.

[0013] According to a second aspect of the present disclosure, a satellite positioning system is provided, including a receiver, the receiver including a first antenna and a second antenna; wherein: The receiver is configured to acquire a target signal, the target signal including a first signal received based on the first antenna and a second signal received based on the second antenna; analyze the target signal to obtain phase difference information between the first signal and the second signal, the phase difference information being used to characterize the phase difference formed when the first signal arrives at the first antenna and the second signal arrives at the second antenna; and determine the direction of arrival of the interference signal based on the phase difference information.

[0014] Optionally, there are multiple receivers, and the satellite positioning system further includes a server; wherein: The receiver is also used to send the current position of the receiver and the direction of arrival to the server; The server is used to obtain the current location and direction of arrival of multiple receivers; and to determine the location of the interference source that sends the interference signal based on the current location of the multiple receivers and the direction of arrival.

[0015] Optionally, the receiver is further configured to: obtain an interference-free phase difference based on the real satellite signals received by the first antenna and the second antenna respectively in an interference-free scenario; determine the satellite direction of arrival of at least one real satellite based on the interference-free phase difference; and determine a zero-value deviation based on the difference between the real direction of the real satellite and the satellite direction of arrival; wherein the zero-value deviation is used to correct the direction of arrival of the interference signal.

[0016] According to a third aspect of the present disclosure, a receiver is provided, including a memory and a processor, the memory being configured to store computer instructions, and the processor being configured to invoke the computer instructions from the memory to perform the method described in the first aspect.

[0017] The satellite signal interference suppression method provided in this disclosure can efficiently and accurately determine the existence of interference signals and suppress them, thereby reducing the impact of interference signals on normal satellite signals and improving the robustness of satellite navigation and positioning.

[0018] Other features and advantages of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the present disclosure and, together with their description, serve to explain the principles of the present disclosure.

[0020] Figure 1 This is a schematic diagram of a satellite positioning system provided in an embodiment of this disclosure.

[0021] Figure 2 This is a schematic flowchart of a satellite signal interference suppression method provided in an embodiment of this disclosure.

[0022] Figure 3 This is a schematic diagram of the structure of a receiver provided in an embodiment of this disclosure. Detailed Implementation

[0023] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present disclosure.

[0024] The following description of at least one exemplary embodiment is merely illustrative and is not intended to limit the scope of this disclosure or its application or use.

[0025] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0026] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0028] The elements involved in the embodiments of this disclosure may represent part or all of an element. For example, the elements involved in the embodiments of this disclosure may be at least a part of an element or all of an element.

[0029] The elements involved in the embodiments of this disclosure may be one or more, such as "a", "the", "the above", "the", "the foregoing", etc., which are used to indicate that the corresponding element is mentioned for the first time or is mentioned again, and do not have the meaning of limiting the number.

[0030] It should be noted that all actions involving the collection, storage, use, processing, transmission, provision, disclosure, and deletion of data in this disclosure are carried out in accordance with the relevant data protection laws and regulations of the country or region where the data is located, and with the full authorization of the relevant data owner.

[0031] Figure 1 This is a schematic diagram of a satellite positioning system 100. (For example...) Figure 1 As shown, the satellite positioning system 100 may include at least a receiver 10. The receiver may be any electronic device capable of receiving satellite signals and performing positioning based on the satellite signals, such as a mobile phone, vehicle terminal, airborne terminal, laptop computer, etc. The receiver may be a mobile device, a fixed device, or a professional receiving device.

[0032] In some examples, the receiver may include multiple antennas deployed at different locations, each capable of independently receiving signals. For instance, the receiver 10 may include a first antenna 111 and a second antenna 121, or more antennas. The signal received by the first antenna may be a first signal, and the signal received by the second antenna may be a second signal. Both the first and second signals may include signals transmitted from the same signal source (e.g., a satellite or interference source) or signals transmitted from different signal sources. Each signal (e.g., the first signal or the second signal) may include signals emitted from one or more signal sources. The relative distance between the first and second antennas is a preset distance, which can be any distance pre-set by the user based on engineering experience, for example, it may be greater than or equal to half the wavelength of the satellite signal.

[0033] For example, such as Figure 1One or more of the satellites 1 and 2, or the interference source 3 shown, can broadcast the target signal as a signal source. Different antennas of the receiver can independently receive the target signal. For example, the signal received by the first antenna can be the first signal, and the signal received by the second antenna can be the second signal. Satellites 1 and 2 can be real satellites that transmit real satellite signals so that the receiver can perform positioning based on these signals. These real satellites can be satellites from the Global Positioning System (GPS), BeiDou Navigation Satellite System (BDS), GLONASS, or other satellite navigation systems. The interference source can be man-made or naturally generated. The interference signal emitted by this source will interfere with the receiver's acquisition and tracking of the real satellite signal, affecting the receiver's positioning accuracy.

[0034] In some examples, the receiver 10 may further include multiple channels, such as a first channel 112 and a second channel 122. The first channel can be connected to a first antenna for tracking and analyzing a first signal received by the first antenna to obtain first observation information corresponding to the first signal. The second channel is connected to a second antenna for tracking and analyzing a second signal received by the second antenna to obtain second observation information corresponding to the second signal. The observation information may include phase information, such as carrier phase or code phase. For example, phase difference information, such as carrier phase difference or code phase difference, can be obtained based on the first and second channels. This phase difference information can be used to characterize the phase difference formed when the first signal arrives at the first antenna and when the second signal arrives at the second antenna. It should be noted that the multiple channels can be hardware-independent channels or logically independent channels that share the same hardware implementation. That is, a channel can be a physical channel or a logical channel. The specific implementation method of the channels is not limited in this embodiment.

[0035] In some examples, the satellite positioning system 100 may include multiple receivers, which may be located in different geographical locations. Optionally, the satellite positioning system 100 may also include a server 20, which can be connected to one or more receivers, for example, via wireless or wired connection. Each receiver can send its current location and other relevant information to the server, which can receive and obtain the current location and other relevant information of each receiver to achieve the corresponding positioning function. It should be noted that the server can be a single server or a distributed server cluster composed of multiple servers, and its deployment method can include local servers or cloud servers.

[0036] In practical applications of satellite positioning, satellite signals are susceptible to various interference sources during propagation, including unintentional interference (such as electromagnetic interference generated by communication equipment and radar) and intentional interference (such as man-made jammers). These interference signals can severely reduce the positioning accuracy of the receiver and may even cause the receiver to malfunction.

[0037] In related technologies, techniques such as spatial filtering, time-domain filtering, or frequency-domain filtering can be used to suppress interference signals. Spatial filtering, in particular, uses an antenna array to form a beam pointing towards the satellite signal while simultaneously creating nulls in the direction of the interference signal, thus suppressing interference. In spatial filtering, a null refers to an antenna array whose gain is zero or close to zero in a specific direction. By aligning the null direction with the interference signal, interference is suppressed, effectively shielding the interference signal in that direction. However, these technologies still have shortcomings in terms of the accuracy and real-time performance of interference signal detection. For example, power detection-based methods are easily affected by signal strength fluctuations, resulting in a high false positive rate and difficulty in meeting robustness requirements.

[0038] Therefore, there is an urgent need for an efficient and accurate method to detect and process interference signals in order to improve the robustness and reliability of satellite positioning systems in complex environments.

[0039] Figure 2 This is a schematic flowchart of a satellite signal interference suppression method provided in an embodiment of this disclosure. The satellite signal interference suppression method can be... Figure 1 The receiver in the satellite positioning system shown performs the operation, and the receiver may include a first antenna and a second antenna. For example... Figure 2 As shown, the satellite signal interference suppression method of this embodiment may include the following steps S210 to S240.

[0040] Step S210: Acquire the target signal.

[0041] The target signal may include a first signal received by a first antenna and a second signal received by a second antenna. The target signal may include satellite signals and / or jamming signals.

[0042] For example, the receiver can receive the target signal synchronously through the first antenna and the second antenna. The target signal may include satellite signals from one or more real satellites (such as satellite 1 and satellite 2) or interference signals from interference sources.

[0043] The aforementioned satellite signals, also known as real satellite signals or satellite navigation signals, are specific electromagnetic wave signals emitted by real satellites (such as GPS or BeiDou navigation satellites) for positioning and / or timing. They possess standardized satellite navigation frequency bands, carrier frequencies, pseudo-random codes (pseudo-codes), and navigation message structures. Receivers can achieve positioning functions by demodulating satellite signals.

[0044] The aforementioned interference signal can be a non-satellite transmitted signal located within the satellite navigation frequency band. This interference signal has a carrier frequency close to that of the actual satellite signal; for example, the frequency difference between the interference signal and the actual satellite signal can be less than or equal to a preset frequency threshold. This interference signal can be a signal modulated with spoofing codes (such as deception interference) or a signal without modulated spoofing codes (such as narrowband or broadband noise interference). This interference signal can be man-made or naturally generated electromagnetic interference that interferes with the receiver's acquisition and tracking of the actual satellite signal, leading to a decrease in the receiver's positioning accuracy or even malfunction.

[0045] In some examples, the power of the interference signal can be greater than, less than, or equal to the power of the real satellite signal. For example, if the power of the interference signal is close to the power of the real satellite signal (i.e., the power difference between the two is less than or equal to a preset power difference threshold), traditional power-based interference suppression methods are unlikely to detect the interference signal, while the interference suppression method of this embodiment can accurately detect the interference signal and suppress it.

[0046] Step S220: Analyze the target signal to obtain the phase difference information of the first signal and the second signal.

[0047] The phase difference information can be used to characterize the phase difference formed when the first signal arrives at the first antenna and the second signal arrives at the second antenna. This phase difference information can reflect the difference in the transmission path of the target signal to the two antennas.

[0048] The phase difference information can be carrier phase difference or code phase difference, etc. Specifically, the carrier phase difference can be the difference between the carrier phase observations corresponding to the first and second signals, used to characterize the phase change caused by the difference in signal propagation paths. The code phase difference can be the phase difference between the pseudo-random codes obtained by analyzing the first and second signals, used to characterize the difference in propagation delay at the chip level.

[0049] It should be noted that the phase in this embodiment can be the phase in three-dimensional space. For example, the direction of the satellite relative to the receiver includes the azimuth angle in the horizontal direction and the elevation angle in the vertical direction. The phase information of the satellite signal can be the phase information in three-dimensional space (e.g., phase difference) obtained by comprehensively considering the azimuth angle and the elevation angle.

[0050] Step S230: Determine whether the receiver has received an interference signal based on the phase difference information.

[0051] Step S240: If it is determined that the receiver has received an interference signal, interference suppression is performed on the interference signal based on the phase difference information.

[0052] In some examples, the receiver can determine the direction of arrival (DOA) of the interfering signal based on this phase difference information. Interference can then be suppressed based on this DOA; for example, the receiver's null direction can be pointed towards the DOA of the interfering signal to suppress it. It should be noted that the DOA of the interfering signal can be represented by the direction of the interfering source relative to the receiver, i.e., the orientation of the interfering source in the receiver's own coordinate system; or it can be represented by the absolute orientation of the interfering source in the Earth's coordinate system.

[0053] In other examples, after the receiver determines the direction of arrival (DOA) of the interfering signal based on the phase difference information, interference suppression can be achieved by alerting the user to handle the interference. For example, the receiver can use lights or sounds to indicate that an interfering signal has been received, or display information such as the DOA or power of the interfering signal on its display device. Alternatively, the receiver can send the DOA and other information of the interfering signal to a connected server, which can then notify the user to suppress the interference.

[0054] In other examples, the filtering weights of the first and second antennas can be determined based on the phase difference information; based on the filtering weights, the signals received from the first and second antennas are filtered to suppress the direction of arrival of interference signals.

[0055] For example, by analyzing phase difference information, the direction of arrival (DOA) of the interfering signal can be accurately determined. By setting the filtering weights of the first and second antennas, these weights are applied to filter the signals received from the two antennas, attenuating the signal component in the DOA of the interfering signal, thereby suppressing the interfering signal. For instance, by setting these filtering weights, the nulls of the array antenna formed by the first and second antennas can be aligned with the DOA of the interfering signal, thus achieving interference suppression. It should be noted that the specific method for determining the DOA of the interfering signal based on the phase difference can also refer to the implementation methods of related technologies, and this disclosure does not limit this aspect.

[0056] Using the technical solution described in steps S210 to S240, the receiver acquires a target signal through a first antenna and a second antenna. This target signal includes a first signal received via the first antenna and a second signal received via the second antenna. The target signal is analyzed to obtain phase difference information between the first and second signals. This phase difference information characterizes the phase difference formed when the first signal reaches the first antenna and the second signal reaches the second antenna. Based on the phase difference information, it is determined whether the receiver has received an interference signal. If it is determined that the receiver has received an interference signal, interference suppression is performed based on the phase difference information. This allows for efficient and accurate determination of the existence of interference signals and suppression of interference, thereby reducing the impact of interference signals on normal satellite signals and improving the robustness of satellite navigation and positioning.

[0057] In some embodiments of this disclosure, the receiver may further include a first channel and a second channel, the first channel being connected to a first antenna and the second channel being connected to a second antenna; in step S220, the receiver may track and analyze the first signal and the second signal based on the first channel and the second channel respectively to obtain phase difference information.

[0058] For example, the first and second channels can use the same loop parameters to track and analyze the first and second signals respectively to obtain the phase difference information. For instance, the receiver can use the same loop parameters to perform high-precision carrier phase observation and / or code phase observation of the first and second signals through the first and second channels respectively, to eliminate common-mode errors such as internal clock skew. In this way, by calculating the difference between the phase observation values ​​of the signal transmitted from the same signal source (e.g., the same satellite) in the two channels, accurate phase difference information is obtained, improving the accuracy of phase difference information detection.

[0059] In some examples, the first signal can be tracked and analyzed based on the first channel to generate target loop parameters for analyzing the first signal; the second signal can be tracked and analyzed based on the second channel using the same target loop parameters as the first channel to obtain phase difference information.

[0060] For example, the first channel can be called the main channel, and the second channel can be called the auxiliary channel. The main channel (first channel) independently completes the accurate tracking of the first signal and generates a set of optimal target loop parameters. Then, this set of target loop parameters is synchronously copied or imposed on the auxiliary channel (second channel). In this way, when the second channel analyzes the second signal, its internal dynamic characteristics are highly consistent with those of the main channel, thereby minimizing the phase deviation introduced by the receiver itself. This ensures that the phase difference measured at the end mainly reflects the spatial propagation difference of the target signal to the two antennas (first antenna and second antenna), thus accurately obtaining the aforementioned phase difference information.

[0061] It should be noted that the specific implementation method for tracking and analyzing satellite signals based on channels can refer to the implementation methods in related technologies. For example, when tracking and analyzing the first signal based on the first channel, signal preprocessing processes such as amplification, down-conversion, and analog-to-digital conversion can be performed first to obtain a digital intermediate frequency signal. Then, conventional acquisition algorithms (such as parallel code phase search) are used to search for the target satellite signal to complete the initial coarse synchronization of carrier frequency and code phase. Then, the loop controller (such as a Costas loop) continuously adjusts its loop parameters (such as the control word of the numerically controlled oscillator, the equivalent noise bandwidth of the loop, and the coefficients of the loop filter) to track the small Doppler changes of the first signal. When each loop of the first channel enters a stable locked state, the loop parameters of the loop controller become the optimal target loop parameters for the current dynamic environment and signal conditions. In the second channel, there is no need to adjust the loop parameters independently based on tracking; the target loop parameters of the first channel can be used directly.

[0062] In this way, by using a master-slave channel design and synchronizing with unified loop parameters, and by forcing the second channel to remain synchronized with the first channel that has already achieved precise tracking, the measurement errors introduced by hardware differences and independent dynamic responses of the two channels are effectively eliminated. This ensures that the measured phase difference purely reflects the spatial propagation characteristics of the signal, significantly improving the purity and accuracy of the phase difference measurement. This provides an extremely reliable data foundation for subsequent interference detection and greatly reduces the false positive rate. Based on this pure phase difference, direction-of-arrival estimation and interference suppression of the interference signal can be performed, enabling the array antenna null to be pointed quickly and accurately at the interference source. This greatly improves the signal-to-interference-plus-noise ratio and positioning continuity of the receiver in complex electromagnetic environments, enhancing the robustness of the navigation and positioning system.

[0063] In other examples, the first signal can be tracked and analyzed based on the first channel to obtain the first phase corresponding to the first signal; the second signal can be tracked and analyzed based on the second channel to obtain the second phase corresponding to the second signal; and the phase difference information can be determined based on the first phase and the second phase.

[0064] In this example, the receiver's two channels (channel one and channel two) can operate completely independently, acquiring phase observations (first phase and second phase) in parallel. Each channel can be equipped with its own complete signal tracking loop and independently acquire, lock onto, and track the signal received by its respective antenna. After acquiring two independent phase observations, the difference between the first phase and the second phase can be directly calculated as the phase difference information.

[0065] This allows for the acquisition of relatively accurate phase difference information. However, since the two channels operate independently, their phase observations introduce clock bias from their respective local oscillators and independent tracking noise, resulting in lower accuracy and higher noise levels in the directly calculated raw phase difference information. In some examples, algorithms such as filtering can be applied to the phase difference information to further improve accuracy.

[0066] In some embodiments of this disclosure, the target signals may be one or more groups, and each group of target signals may include a first signal and a second signal carrying the same target satellite identifier; the phase difference information corresponding to each group of target signals is the phase difference formed when the first signal and the second signal carrying the same target satellite identifier are received by the first antenna and the second antenna, respectively.

[0067] In this way, the receiver can group and correlate target signals using target satellite identifiers to determine whether it has received interference signals, thereby achieving refined and efficient interference detection. For example, the receiver can perform independent, targeted interference assessments for each satellite; or it can achieve more robust interference assessments by considering the relative relationships between multiple satellites.

[0068] In some examples, the receiver can determine the presence of interference signals based on a single satellite. For instance, it can determine whether the phase difference information acquired for a single target satellite matches the theoretical phase difference corresponding to the azimuth angle of that target satellite.

[0069] For example, the method described above for determining whether the receiver has received an interference signal based on phase difference information may include: obtaining antenna position information of the first antenna and the second antenna; obtaining satellite position information of the target satellite corresponding to the target satellite identifier; determining a first theoretical phase difference range corresponding to the target satellite identifier based on the satellite position information and the antenna position information; if the phase difference information is outside the first theoretical phase difference range, it can be determined that the receiver has received an interference signal; conversely, if the phase difference information is within the first theoretical phase difference range, it can be determined that the receiver has not received an interference signal related to the target satellite identifier.

[0070] In this example, the receiver can pre-position itself accurately and determine the antenna positions of its two antennas (the first and second antennas), based on their installation locations (which can be set at the factory). Furthermore, by decoding satellite navigation messages, it can obtain the target satellite's current position in space (satellite position information) in real time. Based on this information, the receiver can construct an accurate geometric model. The direction of the satellite signal (azimuth and elevation) is determined. The path difference between the signal and the two antennas can be directly calculated based on the geometric relationship between the satellite direction and the antenna position information. This path difference (in meters) can be converted into a multiple of the signal wavelength (in meters) to calculate the theoretically observable carrier phase difference (i.e., the theoretical phase difference). Further, due to minor measurement and calculation errors, a reasonable first theoretical phase difference range (e.g., theoretical phase difference ±10 degrees) can be set based on the theoretical phase difference. This first theoretical phase difference range can be used to characterize the boundary of normal fluctuations in the measured phase difference under interference-free conditions.

[0071] Furthermore, by comparing the phase difference information of the target satellite actually determined by the receiver with the first theoretical phase difference range, it can be determined whether the receiver has received an interference signal. For example, if the phase difference information of the target satellite actually determined falls within the first theoretical phase difference range, it means that the direction of the received signal is consistent with the expected direction of the satellite, and it can be determined that the receiver has not received an interference signal related to the target satellite's identifier. As another example, if the phase difference information of the target satellite actually determined is outside the first theoretical phase difference range, it means that the direction of the received signal is different from the expected direction of the satellite, and it can be determined that the receiver has received an interference signal related to the target satellite's identifier.

[0072] By comparing the real-time measured phase difference with the theoretical value calculated based on the satellite's geometric position, abnormal shifts in the signal's direction of arrival can be accurately detected. Once the measured value exceeds the theoretical tolerance range pre-calculated based on the satellite azimuth angle, it clearly indicates the presence of interference signals not originating from the satellite, thus achieving rapid and accurate interference detection. This method effectively avoids the shortcomings of traditional power detection methods, which are susceptible to signal strength fluctuations, and improves the receiver's robustness in detecting interference signals.

[0073] In other examples, the receiver can determine the presence of interference signals by comparing the phase difference information of multiple satellites. For instance, if multiple satellites with theoretically large phase differences (such as two satellites that are completely orthogonal with an azimuth angle difference of 90 degrees) show a situation where their actual phase differences converge, then it can be determined that the receiver has received an interference signal.

[0074] For example, the target signals include a first set of target signals carrying a first satellite identifier and a second set of target signals carrying a second satellite identifier. The azimuth difference between the first satellite azimuth corresponding to the first satellite identifier and the second satellite azimuth corresponding to the second satellite identifier is greater than or equal to a preset azimuth difference threshold. The phase difference information includes a first phase difference corresponding to the first set of target signals and a second phase difference corresponding to the second set of target signals. If the difference between the first phase difference and the second phase difference is less than or equal to the preset phase difference threshold, it can be determined that the receiver has received an interference signal.

[0075] The aforementioned preset azimuth difference threshold can be a value preset by the user based on engineering experience, such as 30 degrees or 90 degrees. The aforementioned preset phase difference threshold can be set based on the preset azimuth difference threshold, for example, it can be a phase difference threshold theoretically calculated based on two satellites with an azimuth angle difference equal to the preset azimuth difference threshold. It should be noted that the preset phase difference threshold can also be a preset, smaller threshold, such as 2 degrees, 5 degrees, or 10 degrees. The preset azimuth difference threshold can be greater than the preset phase difference threshold. It should be noted that the aforementioned azimuth angle difference value can be expressed in absolute value, and the difference between the aforementioned first phase difference and second phase difference can also be expressed in absolute value.

[0076] In this example, the receiver selects two or more satellite identifiers (e.g., a first satellite identifier and a second satellite identifier). The azimuth angles of these two satellites in the sky must have a sufficiently large difference (e.g., the azimuth angle difference is greater than or equal to a preset azimuth difference threshold). Due to their completely different geometric relationships, the theoretical phase difference generated by the signals from these two satellites reaching the dual antennas should be significantly different. The receiver measures the dual antenna phase difference corresponding to the signals from these two satellites (the first satellite and the second satellite), obtaining the first phase difference and the second phase difference. Under normal interference-free conditions, the values ​​of the first and second phase differences will differ depending on the satellite's azimuth, and their difference will be a large value (e.g., greater than the preset phase difference threshold). However, the same interference source can spoof the satellite signals of multiple satellites to achieve the purpose of interfering with and deceiving the receiver. Therefore, for this type of interference source, the directions of arrival of the interference signals corresponding to different satellite identifiers are basically the same, and thus the detected phase differences will also be basically the same (e.g., less than the preset phase difference threshold).

[0077] In this way, the receiver achieves efficient and accurate detection of deceptive interference by comparing and analyzing the phase difference information of at least two satellites from different spatial azimuths. This allows it to effectively identify and distinguish between genuine satellite signals and multiple deceptive signals forged by a single interference source. When the measured phase differences from multiple satellites with significantly different azimuth angles show an abnormal convergence, a common interference source can be identified. This method does not rely on the receiver's precise positioning results; it relies solely on logical judgment based on the spatial direction-of-arrival characteristics of the signal, significantly improving the receiver's robustness in detecting interference signals in complex environments.

[0078] This disclosure also provides a satellite positioning system, such as Figure 1 As shown, the satellite positioning system may include a receiver, which may include a first antenna and a second antenna.

[0079] The receiver can be used to acquire a target signal, which includes a first signal received based on a first antenna and a second signal received based on a second antenna; the target signal is analyzed to obtain phase difference information between the first signal and the second signal, which is used to characterize the phase difference formed when the first signal arrives at the first antenna and the second signal arrives at the second antenna; the direction of arrival of the interference signal is determined based on the phase difference information.

[0080] Using this system, the direction of arrival of the interference source relative to the receiver can be accurately located, making it convenient for users to troubleshoot the interference source in that direction of arrival.

[0081] In some examples, the receiver's two antennas and / or two channels may have inherent differences. For example, the antennas themselves, the cables in the channels, amplifiers, and other hardware modules, or the software processing modules may have inherent differences in relevant parameters or processing delays. This can lead to a discrepancy between the direction of arrival (DOA) of the interfering signal determined solely based on phase difference information and the actual direction of the interfering signal. Even in interference-free scenarios, when the receiver receives and analyzes the phase difference of the real satellite signal, the direction of the real satellite signal determined based on this phase difference will still differ from the actual direction. Therefore, it is possible to first determine the zero-value deviation introduced by the two antennas and / or two channels themselves (i.e., the direction deviation in interference-free scenarios). This zero-value deviation can be used to correct the DOA of the interfering signal, meaning that the DOA of the interfering signal can be determined when an interfering signal is present, thereby improving the accuracy of interfering signal direction localization.

[0082] For example, the receiver can determine the zero-value deviation by: obtaining the interference-free phase difference based on the real satellite signals received by the first and second antennas respectively in an interference-free scenario; determining the direction of arrival (DOA) of at least one real satellite based on the interference-free phase difference; and determining the zero-value deviation based on the difference between the real satellite's true direction and the DOA. The real direction of the real satellite can be determined based on information such as the satellite's position, the receiver's current position, and the positions of the first and second antennas. The interference-free scenario can be determined by the receiver based on the phase difference information, using the method described in the foregoing embodiments of this disclosure, to indicate that the receiver has not received any interference signals. Optionally, the user can initiate the zero-value deviation calibration in an interference-free environment. When the user initiates the zero-value deviation calibration, the receiver can default to an interference-free scenario. It should be noted that the specific method for determining the satellite DOA or the interference signal DOA based on the phase difference can be found in the descriptions in related technologies, and will not be repeated in this embodiment.

[0083] Furthermore, the receiver can determine the direction of arrival (DOA) of the interference signal by determining the DOA based on the zero-value deviation and phase difference information. For example, the initial DOA of the interference signal can be determined based on the phase difference information, and the initial DOA can be corrected based on the zero-value deviation to obtain the DOA. For instance, the sum of the initial DOA and the zero-value deviation can be used as the DOA.

[0084] The above methods can further improve the accuracy of locating the direction of arrival of interference signals.

[0085] In some examples, the satellite positioning system may include multiple receivers, and the satellite positioning system may also include a server.

[0086] The receiver can also be used to send the receiver's current location and direction of arrival to the server.

[0087] The receiver's current position can be determined by the receiver based on satellite signals when it is not interfered with, or it can be pre-configured. For example, the receiver can be placed in a fixed position and that fixed position can be used as the receiver's current position.

[0088] In some examples, the receiver may perform some or all of the steps of the satellite signal interference suppression method in the foregoing embodiments of this disclosure to determine whether the receiver has received an interference signal and to determine the direction of arrival of the interference signal.

[0089] The server can be used to obtain the current location and direction of arrival of multiple receivers; based on the current location and direction of arrival of multiple receivers, the location of the interference source transmitting the interference signal can be determined.

[0090] In some examples, the aforementioned multiple receivers are two or more receivers, which can be distributed in different geographical locations. The server performs cross-sectional analysis based on the geographical locations of the multiple receivers and the direction of arrival of the interference signals detected by each receiver, thereby determining the location of the interference source that sent the interference signal.

[0091] It should be noted that due to measurement errors (such as phase difference measurement noise, receiver position error, and azimuth calculation error), the location of the interference source can be a region. For example, mathematical algorithms such as the least squares method can be used to determine the location of the interference source. The least squares method can be used to find a target point that minimizes the sum of the squares of the distances (vertical distances) from this target point to the azimuth lines emitted by all receivers. This calculated target point can be used as the most probable location of the interference source estimated by the algorithm.

[0092] By using this system, the actual physical location of the interference source can be accurately located through multiple receivers, enabling proactive detection and precise tracing of the interference source. This provides a clear target for subsequent interference source investigation and greatly enhances the proactive defense capability of the entire satellite positioning system against intentional and malicious interference.

[0093] Figure 3 This is a schematic diagram of the structure of a receiver provided in an embodiment of this disclosure. Figure 3 As shown, the receiver 10 may include a memory 1010 and a processor 1020. The memory 1010 may be used to store computer instructions, and the processor 1020 may be used to retrieve computer instructions from the memory 1010 to execute all or part of the steps of any of the methods in the foregoing embodiments of this disclosure. The processor may be one or more, and the one or more processors may execute the instructions individually or jointly. The memory may also be one or more, and the one or more memories may store the aforementioned computer instructions individually or jointly. Optionally, the receiver may be, for example...Figure 1 The receiver shown.

[0094] In some examples, the receiver can acquire a target signal, which includes a first signal received based on a first antenna and a second signal received based on a second antenna; analyze the target signal to obtain phase difference information between the first signal and the second signal, the phase difference information being used to characterize the phase difference formed when the first signal arrives at the first antenna and the second signal arrives at the second antenna; and determine the direction of arrival of the interference signal based on the phase difference information.

[0095] This disclosure also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any of the methods in the foregoing embodiments of this disclosure. Optionally, the computer-readable storage medium may be a non-transitory storage medium, but is not limited thereto, and may also be a temporary storage medium.

[0096] This disclosure also provides a chip that may include a processing unit, which can be used to execute all or part of the steps of any of the methods in the foregoing embodiments of this disclosure. The chip may be in the form of an Application-Specific Integrated Circuit (ASIC), a System-on-Chip (SOC), a Field-Programmable Gate Array (FPGA), etc., and this embodiment is not limited to this. Optionally, the chip may further include a storage unit, which can be used to store computer instructions. The processing unit can be used to retrieve the computer instructions from the storage unit to execute all or part of the steps of any of the methods in the foregoing embodiments of this disclosure.

[0097] This disclosure also provides a computer program product that may include a computer program that, when executed by a processor, can implement any of the methods described in the foregoing embodiments of this disclosure.

[0098] This disclosure may be a system, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement any of the methods in the foregoing embodiments of this disclosure.

[0099] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media may include, for example, electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), static random access memory (SRAM), compact disc-read-only memory (CD-ROM), digital versatile disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any combination thereof. The computer-readable storage medium used herein is not to be interpreted as a transient signal itself, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0100] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0101] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​(e.g., Smalltalk, C++, etc.) and conventional procedural programming languages ​​(e.g., the "C" language or similar programming languages). The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network (e.g., a local area network or a wide area network), or it may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays, or programmable logic arrays, may execute computer-readable program instructions to implement various aspects of the embodiments of this disclosure by utilizing state information from the computer-readable program instructions.

[0102] Various aspects of this disclosure are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0103] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0104] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions that execute on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0105] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions. It should be noted that implementation in hardware, implementation in software, and implementation using a combination of software and hardware are all equivalent.

[0106] The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, and are not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein. The scope of this disclosure is defined by the appended claims.

Claims

1. A method for suppressing satellite signal interference, characterized in that, Applied to a receiver, the receiver including a first antenna and a second antenna; the method includes: Acquire a target signal; wherein the target signal includes a first signal received based on the first antenna and a second signal received based on the second antenna; The target signal is analyzed to obtain the phase difference information between the first signal and the second signal; wherein, the phase difference information is used to characterize the phase difference formed when the first signal arrives at the first antenna and the second signal arrives at the second antenna; Based on the phase difference information, determine whether the receiver receives an interference signal; If it is determined that the receiver has received an interference signal, interference suppression is performed on the interference signal based on the phase difference information.

2. The method according to claim 1, characterized in that, The receiver further includes a first channel and a second channel, wherein the first channel is connected to the first antenna and the second channel is connected to the second antenna; The phase difference information between the first signal and the second signal is obtained by parsing the target signal, including: The phase difference information is obtained by tracking and analyzing the first signal and the second signal based on the first channel and the second channel, respectively.

3. The method according to claim 2, characterized in that, Based on the first channel and the second channel respectively, the first signal and the second signal are tracked and analyzed to obtain the phase difference information, including: Based on the first channel, the first signal is tracked and analyzed to generate target loop parameters for analyzing the first signal; The second channel uses the same target loop parameters as the first channel to track and analyze the second signal, thereby obtaining the phase difference information.

4. The method according to claim 2, characterized in that, The step of tracking and analyzing the first signal based on the first channel and the second signal based on the second channel to obtain the phase difference information includes: Based on the first channel, the first signal is tracked and analyzed to obtain the first phase corresponding to the first signal; Based on the second channel, the second signal is tracked and analyzed to obtain the second phase corresponding to the second signal; The phase difference information is determined based on the first phase and the second phase.

5. The method according to any one of claims 1 to 4, characterized in that, The target signals are one or more groups, and each group of target signals includes a first signal and a second signal carrying the same target satellite identifier; the phase difference information corresponding to each group of target signals is the phase difference formed when the first signal and the second signal carrying the same target satellite identifier are received by the first antenna and the second antenna, respectively.

6. The method according to claim 5, characterized in that, Determining whether the receiver receives an interference signal based on the phase difference information includes: Obtain the antenna position information of the first antenna and the second antenna; Obtain the satellite position information of the target satellite corresponding to the target satellite identifier; Based on the satellite position information and the antenna position information, determine the first theoretical phase difference range corresponding to the target satellite identifier; If the phase difference information is outside the first theoretical phase difference range, then it is determined that the receiver has received the interference signal.

7. The method according to claim 5, characterized in that, The target signal includes a first set of target signals carrying a first satellite identifier and a second set of target signals carrying a second satellite identifier. The azimuth difference between the first satellite azimuth corresponding to the first satellite identifier and the second satellite azimuth corresponding to the second satellite identifier is greater than or equal to a preset azimuth difference threshold. The phase difference information includes a first phase difference corresponding to the first group of target signals and a second phase difference corresponding to the second group of target signals; Determining whether the receiver receives an interference signal based on the phase difference information includes: If the difference between the first phase difference and the second phase difference is less than or equal to a preset phase difference threshold, then it is determined that the receiver has received the interference signal.

8. The method according to any one of claims 1 to 4, characterized in that, The interference suppression based on the phase difference information includes: The filtering weights of the first antenna and the second antenna are determined based on the phase difference information; Based on the filtering weights, the signals received from the first antenna and the second antenna are filtered to suppress the direction of arrival of the interference signals.

9. A satellite positioning system, characterized in that, Includes a receiver, the receiver comprising a first antenna and a second antenna; wherein: The receiver is configured to acquire a target signal, the target signal including a first signal received based on the first antenna and a second signal received based on the second antenna; analyze the target signal to obtain phase difference information between the first signal and the second signal, the phase difference information being used to characterize the phase difference formed when the first signal arrives at the first antenna and the second signal arrives at the second antenna; and determine the direction of arrival of the interference signal based on the phase difference information.

10. The satellite positioning system according to claim 9, characterized in that, The receivers are multiple, and the satellite positioning system further includes a server; wherein: The receiver is also used to send the current position of the receiver and the direction of arrival to the server; The server is used to obtain the current location and direction of arrival of multiple receivers; and to determine the location of the interference source that sends the interference signal based on the current location of the multiple receivers and the direction of arrival.

11. The satellite positioning system according to claim 9, characterized in that, The receiver is further configured to: obtain an interference-free phase difference based on the real satellite signals received by the first antenna and the second antenna respectively in an interference-free scenario; determine the satellite direction of arrival of at least one real satellite based on the interference-free phase difference; and determine a zero-value deviation based on the difference between the real direction of the real satellite and the satellite direction of arrival; wherein the zero-value deviation is used to correct the direction of arrival of the interference signal.

12. A receiver, characterized in that, The method includes a memory and a processor, the memory being used to store computer instructions, and the processor being used to retrieve the computer instructions from the memory to perform the method of any one of claims 1 to 8.

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