Positioning method, positioning device and readable storage medium

Abstract

The invention relates to a positioning method, a positioning device and a readable storage medium, and relates to the technical field of satellite navigation. The positioning method is applied to a receiver, and the receiver receives a pseudo-satellite signal sent by a pseudo-satellite base station simulation target satellite; wherein the target satellite is a satellite which is invisible at the position of the receiver; analyzing the pseudo satellite signal to obtain a pseudo satellite navigation message of the target satellite; analyzing a real satellite signal sent by a real satellite according to the pseudo satellite navigation message of the target satellite to obtain a real satellite navigation message of the real satellite; and determining the position of the receiver according to the real satellite navigation message.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to the field of satellite navigation technology, and more specifically, to a positioning method, a positioning device, and a readable storage medium. Background Art

[0002] Satellite navigation systems (such as GPS) have become a widely used core tool in positioning technology, providing high-precision positioning services for various receivers. However, in complex environments such as urban canyons, indoor spaces, and tunnels, satellite signals may be blocked or reflected, resulting in signal weakening or distortion, which can affect positioning results.

[0003] Therefore, how to improve the positioning reliability of the receiver in complex environments has become a problem that needs to be solved. Summary of the Invention

[0004] An object of the embodiments of the present disclosure is to provide a positioning method, a positioning device, and a readable storage medium, which can improve the positioning accuracy of a receiver.

[0005] According to a first aspect of the present disclosure, a positioning method is provided, which is applied to a receiver and includes: receiving a pseudo-satellite signal emitted by a pseudo-satellite base station simulating a target satellite; wherein the target satellite is a satellite that is invisible from the receiver's location; parsing the pseudo-satellite signal to obtain a pseudo-satellite navigation message from the target satellite; parsing a real satellite signal emitted by a real satellite based on the pseudo-satellite navigation message from the target satellite to obtain a real satellite navigation message from the real satellite; and determining the receiver's position based on the real satellite navigation message.

[0006] Optionally, the real satellite signal sent by the real satellite is parsed according to the pseudo-satellite navigation message of the target satellite to obtain the real satellite navigation message of the real satellite, including: determining the theoretical pseudo-range Doppler reference value and the local clock deviation reference value according to the pseudo-satellite navigation message; determining the code phase and Doppler frequency range to be searched when parsing the real satellite signal according to the theoretical pseudo-range Doppler reference value and the local clock deviation reference value; and parsing the real satellite signal sent by the real satellite based on the code phase and the Doppler frequency range to obtain the real satellite navigation message of the real satellite.

[0007] Optionally, the real satellite signal sent by the real satellite is parsed according to the pseudo-satellite navigation message of the target satellite, including: predicting the message bit change law of the real satellite navigation message according to the pseudo-satellite navigation message; and performing coherent integration on the real satellite signal according to the message bit change law to parse the real satellite signal and obtain the real satellite navigation message of the real satellite.

[0008] Optionally, coherent integration is performed on the real satellite signal according to the message bit change rule to parse the real satellite signal and obtain the real satellite navigation message of the real satellite, including: adjusting the coherent integration sign of the real satellite signal according to the message bit change rule to generate a standard signal-to-noise ratio signal greater than a preset signal-to-noise threshold; and performing parsing based on the standard signal-to-noise ratio signal to obtain the real satellite navigation message corresponding to the real satellite signal.

[0009] Optionally, predicting a message bit change pattern of a real satellite navigation message based on the pseudo-satellite navigation message includes: predicting a symbol change pattern at a message bit boundary in the real satellite navigation message based on almanac information in the pseudo-satellite navigation message; and determining a message bit change pattern based on the symbol change pattern at the message bit boundary.

[0010] Optionally, the coherent integration sign of the real satellite signal is adjusted according to the change rule of the telegram bit to generate a standard signal-to-noise ratio signal greater than a preset signal-to-noise threshold, including: adjusting the coherent integration sign of the real satellite signal at the telegram bit boundary to eliminate the sign change of the in-direction / orthogonal branch integration value caused by the change of the telegram bit sign, and generating the standard signal-to-noise ratio signal.

[0011] Optionally, based on the almanac information in the pseudo-satellite navigation message, the symbol change pattern at the message bit boundary in the real satellite navigation message is predicted, including: using the time information in the pseudo-satellite signal to synchronize the local time counter, and obtaining a time reference point for synchronizing the local time counter with the satellite system time, the time information including the second of the week TOW and the week number WN; determining the start bit and end bit of each frame message in the real satellite navigation message based on the obtained time reference point and the navigation message structure of the real satellite navigation message; determining the message bit boundary based on the start bit and the end bit; and predicting the symbol change pattern at the message bit boundary.

[0012] According to a second aspect of the present disclosure, a positioning method is also provided, which is applied to a pseudo-satellite base station, including: determining a target satellite simulated by the pseudo-satellite base station; wherein the target satellite is a satellite that is invisible at the position of the receiver; sending a pseudo-satellite signal from the simulated target satellite, wherein the pseudo-satellite signal is used by the receiver to parse the pseudo-satellite signal to obtain a pseudo-satellite navigation message of the target satellite, parsing a real satellite signal sent by a real satellite based on the pseudo-satellite navigation message of the target satellite to obtain a real satellite navigation message of the real satellite; and determining the position of the receiver based on the real satellite navigation message.

[0013] According to a third aspect of the present disclosure, an electronic device is further provided, comprising a memory and a processor, wherein the memory is used to store a computer program; and the processor is used to execute the computer program to implement the method according to the first aspect of the present disclosure.

[0014] According to a fourth aspect of the present disclosure, a computer-readable storage medium is further provided, on which a computer program is stored. When the computer program is executed by a processor, the method according to the first aspect of the present disclosure is implemented.

[0015] One beneficial effect of the embodiments of the present disclosure is that the receiver receives invisible satellite signals simulated by pseudo-satellite base stations and uses the pseudo-satellite navigation messages in the signals to assist in parsing real satellite signals, thereby improving the capture and resolution of real satellite signals in various environments, solving the problem of the receiver having difficulty in obtaining sufficient effective signals for accurate positioning due to obstruction or weakening of satellite signals, and significantly improving the positioning reliability of the receiver.

[0016] Other features and advantages of the embodiments of the present disclosure will become apparent from the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the embodiments of the present disclosure.

[0018] Figure 1 is a schematic diagram of the structure of a positioning system to which one embodiment of the present invention can be applied;

[0019] Figure 2 is applied to Figure 1 Flowchart of receiver positioning method;

[0020] Figure 3 is applied to Figure 1 Flow chart of pseudo-satellite base station positioning method;

[0021] Figure 4 is a schematic diagram of the hardware structure of an electronic device according to an embodiment. DETAILED DESCRIPTION

[0022] 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 of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present disclosure.

[0023] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present disclosure, its application, or uses.

[0024] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0025] In all examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0026] It should be noted that like reference numerals and letters refer to like items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0027] Figure 1 FIG2 shows a schematic architecture diagram of a positioning system applicable to an embodiment of the present disclosure. Figure 1 The positioning system may include satellites 110, pseudo-satellite base stations 130, and receivers 140. Satellites 110 may be classified into two types: visible satellites 111 and invisible satellites 112, depending on the location of the receiver. Signals transmitted by visible satellites 111 may be directly received by receiver 140 and used to generate real satellite observation data. Invisible satellites 112 are invisible to receiver 140, meaning that the receiver cannot receive signals from these invisible satellites or deems them invalid and does not use them for positioning.

[0028] For example, for a receiver located anywhere on Earth, there are theoretically both visible and invisible satellites. For example, GPS has 32 satellites, but theoretically, a receiver located anywhere near the Earth's surface can only see 8-12 satellites. These 8 to 12 visible satellites are considered visible satellites at the receiver's location. The remaining 20 or more satellites are invisible to the receiver and are considered invisible satellites at the receiver's location.

[0029] In some examples, after the receiver is first positioned, it calculates the relative relationship between each satellite in the sky and the receiver to obtain the elevation angle of each satellite. If the elevation angle of a satellite is lower than 0 (that is, the position of the satellite is below the horizon at the receiver's location), it can be determined that the satellite is invisible. In this case, even if the receiver receives the signal of the invisible satellite, it will not use it. This is because the receiver determines that the signal of the invisible satellite may be affected by multipath effects or other interference, and there is a high probability that there is a problem. Therefore, the signal of the invisible satellite is regarded as invalid and not used.

[0030] In an embodiment of the present disclosure, a novel positioning system can be provided, wherein the pseudolite base station 130 in the positioning system can simulate an invisible satellite and emit a pseudolite signal; the receiver 140 can receive and use the pseudolite signal for positioning, thereby enhancing the positioning accuracy of the receiver in complex environments.

[0031] Pseudo-satellite base station 130: This can be used to enhance satellite signal coverage or provide additional satellite signal processing capabilities. This pseudo-satellite base station can also be referred to as a pseudo-base station, ground base station, etc. This pseudo-satellite base station can be used to simulate signals from real satellites. In some examples, pseudo-satellite base station 130 can simulate signals from invisible satellites 112 and transmit these pseudo-satellite signals to receiver 140. Pseudo-satellite base station 130 can determine the simulated target satellite based on the pseudo-satellite group mapping relationship and transmit the corresponding pseudo-satellite signal. This pseudo-satellite signal can be used to determine auxiliary positioning information for the pseudo-satellite base station, which can include information such as the base station's position and clock bias.

[0032] Receiver 140: This can be a mobile device, a fixed device, or a specialized receiving device, and can be used to receive satellite signals and perform positioning based on them. In some examples, receiver 140 can receive at least one of pseudolite signals from pseudolite base station 130 and real satellite signals from visible satellites 111. Receiver 140 can also determine the satellite coordinates and measure pseudoranges of target satellites based on the pseudolite signals, determine auxiliary positioning information for pseudolite base station 130 based on this information, and determine the receiver's own position based on the auxiliary positioning information.

[0033] In some examples, there may be multiple pseudolite base stations 130, each of which can simulate a different target satellite, which may be a satellite that is not visible from the receiver's location. After acquiring auxiliary positioning information from at least four pseudolite base stations, receiver 140 can calculate its own position. Furthermore, receiver 140 can generate virtual satellite observation data based on the auxiliary positioning information from pseudolite base stations 130 to determine its own position. Alternatively, receiver 140 can combine the auxiliary positioning information from pseudolite base stations 130 with satellite observation data from visible satellites 111 to determine its own position.

[0034] Due to the openness and fragility of satellite signals, they are susceptible to interference from spoofing signals, thus affecting the accuracy and security of satellite navigation positioning. Based on this, embodiments of the present disclosure provide a positioning method that performs a credibility check on received pseudolite signals before positioning to ensure that the pseudolite signals used for positioning are credible. This not only improves the security of positioning results, but also protects the accuracy of positioning results from interference from spoofing signals.

[0035] Figure 2 This is a flow chart of a positioning method provided by an embodiment of the present disclosure. Figure 1 The receiver 140 in the positioning system shown performs, for example Figure 2 As shown, the method may include the following steps S210 to S240.

[0036] Step S210: Receive a pseudolite signal sent by a pseudolite base station simulating a target satellite.

[0037] The target satellite is a satellite that is not visible from the location of the receiver.

[0038] The target satellite may be at least one invisible satellite, and the receiver may be a receiver capable of receiving pseudolite signals transmitted by a pseudolite base station. For example, the receiver may be located at a location capable of receiving pseudolite signals transmitted by the pseudolite base station, that is, within the coverage area of the pseudolite signals transmitted by the pseudolite base station. For example, if, according to design and planning, the pseudolite signals transmitted by the pseudolite base station can cover a coverage area with a radius of 500 meters centered on the pseudolite base station's transmitting antenna, the receiver may be located within this coverage area.

[0039] In some examples, a pseudo-satellite base station can use a space and time synchronization control mechanism based on a ground-based augmentation network to use a satellite that is not visible at the receiver's location (for example, a satellite whose connection between the receiver and the satellite is blocked by buildings or terrain) as a target satellite. The pseudo-satellite base station simulates and generates a pseudo-satellite signal with the same frequency, modulation mode and data structure as the target satellite through technical means such as carrier phase reconstruction and navigation message remapping, and ensures that each base station signal is strictly synchronized with the Global Navigation Satellite System (GNSS) time scale through a time synchronization system. The pseudo-satellite signal simulated by the pseudo-satellite base station can contain information such as the ephemeris, almanac, and pseudo-range observation data of the target satellite, but its transmitting source is a pseudo-satellite base station on the ground rather than a real satellite in the sky. Pseudo-satellite signals can be used to supplement the deficiencies of real satellite signals, especially in environments where satellite signals are blocked or weakened (such as indoors, in tunnels or urban canyons).

[0040] In some examples, the pseudolite base station may determine the target satellite simulated by the pseudolite base station based on a pseudolite group mapping relationship. The pseudolite group mapping relationship may be obtained in various ways. For example, the pseudolite group mapping relationship may be a mapping relationship between target satellites and pseudolite base stations pre-set by the pseudolite base station. In another example, the pseudolite group mapping relationship may be a mapping relationship between target satellites and pseudolite base stations obtained by the pseudolite base station from a preset server.

[0041] Step S220: Analyze the pseudolite signal to obtain the pseudolite navigation message of the target satellite.

[0042] Among them, pseudolite navigation messages can be understood as a collection of navigation data generated by pseudolite base stations to simulate invisible satellites. For example, a pseudolite base station generates navigation message data based on the orbital parameters and time information of the target satellite. Its structure and content are similar to real satellite navigation messages, but it contains relevant information about the target satellite simulated by the pseudolite. This pseudolite navigation message contains data such as the ephemeris and almanac of the target satellite, which is used to assist the receiver in capturing and resolving real satellite signals. Specifically, the ephemeris data in the pseudolite navigation message can help the receiver predict the position of the target satellite at a specific time, while the almanac data provides approximate orbital information for the entire satellite constellation, allowing the receiver to quickly understand the approximate position of all satellites in the sky, thereby more efficiently searching and locking on to satellites, improving the efficiency and success rate of positioning.

[0043] Step S230: parsing the real satellite signal sent by the real satellite according to the pseudo-satellite navigation message of the target satellite to obtain the real satellite navigation message of the real satellite.

[0044] Here, a real satellite can be understood as a satellite that is visible from the receiver's location and can directly transmit signals to the receiver. The real satellite signal transmitted by the real satellite can be understood as a navigation signal generated and transmitted by the real satellite according to its own orbital parameters and time information. It contains the navigation message data of the real satellite, which is used by the receiver to determine its own position. In this step, the receiver uses reference data such as the orbital parameters and time information of the target satellite provided in the pseudolite navigation message to parse the real satellite signal. Specifically, based on the almanac information in the pseudolite navigation message, the receiver can predict the message bit variation pattern in the real satellite signal. When coherently integrating the real satellite signal, the receiver can adjust the integral sign based on this variation pattern, eliminating the sign changes of the in-direction / orthogonal branch integral values caused by message bit sign changes, and generate a standard signal-to-noise ratio signal greater than a preset signal-to-noise threshold. Based on this standard signal-to-noise ratio signal, the receiver can more accurately parse the real satellite navigation message of the real satellite, thereby providing more reliable data support for subsequent positioning solutions.

[0045] Step S240: Determine the position of the receiver according to the real satellite navigation message.

[0046] In this implementation method, the receiver receives invisible satellite signals simulated by pseudo-satellite base stations and uses the pseudo-satellite navigation messages in the signals to assist in parsing real satellite signals. This improves the capture and resolution of real satellite signals in various environments, solves the problem of the receiver having difficulty obtaining sufficient effective signals for precise positioning due to obstruction or weakening of satellite signals, and significantly improves the receiver's positioning accuracy.

[0047] In some embodiments of the present disclosure, the above step S230 may include the following steps S231 to S233:

[0048] Step S231: Determine a theoretical pseudorange Doppler reference value and a local clock bias reference value according to the pseudolite navigation message.

[0049] Step S232: Determine the code phase and Doppler frequency range to be searched when parsing the real satellite signal based on the theoretical pseudorange Doppler reference value and the local clock bias reference value.

[0050] Step S233: parsing the real satellite signal sent by the real satellite based on the code phase and Doppler frequency range to obtain the real satellite navigation message of the real satellite.

[0051] It should be noted that after the receiver has initially located and acquired the target satellite's ephemeris, it can determine whether the target satellite is visible or invisible. Prior to this, it is not known that these target satellites are invisible, so it will attempt to use and process them as visible satellites. Furthermore, even if these target satellites are invisible, the receiver will still acquire and track them. It will only not use these target satellites for position calculations during the position, velocity, and time (PVT) solution. This is essentially similar to the treatment of other visible satellites with excessively large pseudorange residuals, which are not included in the calculation. Each satellite will only broadcast its own ephemeris in subframes 1, 2, and 3, but will also broadcast the almanacs of other satellites in subframes 4 and 5.

[0052] Because the signals transmitted by pseudo-satellite base stations simulating target satellites originate from the ground and have adjustable power, they are typically stronger and of higher quality. When weather conditions restrict bit synchronization using sky-based satellite signals, the signals from ground-based pseudo-satellites are more easily synchronized. This allows for earlier acquisition of important information such as time, initial position, local clock error, and frequency error, as well as the almanac information for all satellites in the sky. This allows the receiver to determine reference values for the target or real satellite, such as the theoretical pseudo-range Doppler and local clock deviation. Furthermore, when attempting to acquire a real, visible satellite, the receiver can use these reference values to further compress the code phase and Doppler frequency ranges required to acquire the real satellite signal. This reduces the search step size while maintaining equivalent computing performance, improving search accuracy and acquisition success rate.

[0053] Suppose a receiver is located in an urban canyon, surrounded by tall buildings. This means that only a few real satellites are visible to the receiver. To improve positioning accuracy, multiple pseudolite base stations are deployed, each simulating signals from a group of invisible satellites. The receiver first captures these pseudolite signals and interprets them as real satellite signals based on the information contained in the pseudolite navigation messages.

[0054] The receiver estimates the Doppler shift and code phase offset of the real satellite signal based on the almanac information in the pseudolite navigation message. For example, by using the almanac information in the pseudolite navigation message to determine the position and velocity of the target satellite at a specific time, the receiver can calculate the Doppler shift and code phase offset of the satellite signal. Based on these calculated Doppler shift and code phase offset, the receiver determines the signal acquisition window. For example, if the Doppler shift is 100 Hz and the code phase offset is 0.5 chips, the receiver limits the search range to ±100 Hz of the Doppler frequency and ±0.5 chips of the code phase. The receiver then combines the target satellite's observation data (such as pseudorange and Doppler shift) with the observation data of the real visible satellites to construct a positioning equation system that includes the receiver's coordinates. For example, if the receiver captures the signals of one real satellite and three target satellites, the observation data from these four satellites is used to construct a positioning equation system that includes the receiver's three-dimensional coordinates and clock bias.

[0055]

[0056] Among them, ρ1 and (x1, y1, z1) are the measured pseudorange and three-dimensional coordinates of the first real satellite, (x2, y2, z2), ρ2, (x3, y3, z3), ρ3, (x4, y4, z4), ρ4 are the three-dimensional coordinates and measured pseudoranges of the three target satellites respectively, (x r ,y r , z r ) is the three-dimensional coordinate of the receiver, c is the speed of light, Δt r is the receiver's local clock difference.

[0057] By solving the positioning equations, the receiver position is determined.

[0058] In this example, pseudo-satellite navigation messages are used to determine the theoretical pseudo-range Doppler reference value and local clock deviation reference value, and based on this, the code phase and Doppler frequency range when parsing real satellite signals are determined. This effectively reduces the search space of the receiver when capturing real satellite signals, improves signal capture efficiency, and thus speeds up positioning.

[0059] In some other embodiments of the present disclosure, the above step S230 may include the following steps S236 to S237:

[0060] Step S236: Obtaining a message bit variation pattern of the real satellite navigation message based on the pseudo-satellite navigation message prediction.

[0061] For example, the almanac information in the pseudo-satellite navigation message can be used to predict the message bit variation pattern in the real satellite signal, so that the receiver can adjust the coherent integration symbol according to the predicted message bit variation pattern.

[0062] Although only invisible satellite signals from pseudolites are captured, pseudolites also broadcast the almanac of all satellites in the sky while broadcasting their own ephemeris parameters. Many parameters in the almanac message of the same satellite are similar to the ephemeris parameters (the high bits are the same, and the only difference is the lower bits). In addition, subframes 4 and 5, as well as time-related parameters such as the time of week (TOW) and / or week number (WN) broadcast by all satellites are exactly the same. Therefore, after obtaining this information from pseudolites, the receiver can determine the bit change pattern of the message.

[0063] Step S237: performing coherent integration on the real satellite signal according to the message bit variation rule to parse the real satellite signal and obtain the real satellite navigation message of the real satellite.

[0064] When capturing and tracking satellites visible in the sky, the receiver uses these known message bit change patterns to eliminate the sign changes of the in-phase component integration value / quadrature component integration value (I / Q) caused by changes in the message bit signs. If this is not eliminated, the positive and negative signs of the message bits cancel each other out, and the integration value cannot continue to increase after crossing the message bit boundary. This achieves ultra-long coherent integration and improves the probability of signal capture and tracking.

[0065] In this embodiment, the message bit change pattern of the real satellite navigation message is predicted based on the pseudo-satellite navigation message, and the real satellite signal is coherently integrated accordingly, thereby enhancing the receiver's ability to capture and track the real satellite signal and providing more reliable data support for high-precision positioning.

[0066] In some examples, step S237 may include the following steps S2371 to S2372:

[0067] Step S2371: adjusting the coherent integration sign of the real satellite signal according to the bit variation rule of the message to generate a standard signal-to-noise ratio signal greater than a preset signal-to-noise threshold.

[0068] In some examples, the telegram bit change pattern may include the symbol change pattern at the telegram bit boundary in the real satellite navigation telegram; the coherent integration symbol of the real satellite signal may be adjusted at the telegram bit boundary to eliminate the I / Q path integral value sign change caused by the telegram bit sign change, thereby generating a standard signal-to-noise ratio signal.

[0069] For example, the pseudo-satellite signal captured by the receiver exhibits a sign change pattern of "10101010" at the message bit boundaries, meaning the sign of every other bit flips. Based on this pattern, the receiver adjusts the sign of the integral at each message bit boundary when coherently integrating the real satellite signal. Specifically, when the receiver detects a message bit boundary in the real satellite signal, if the current bit is "1" and the next bit is "0," the integral sign at the boundary is changed from positive to negative. Conversely, if the current bit is "0" and the next bit is "1," the integral sign is changed from negative to positive. This eliminates the sign change of the I / Q path integral value caused by the message bit sign change, generating a standard signal-to-noise ratio signal.

[0070] In this example, the coherent integration sign of the real satellite signal is adjusted at the message bit boundary, effectively eliminating the sign change of the I / Q path integration value caused by the message bit sign change, generating a standard signal-to-noise ratio signal, improving the coherent integration effect of the signal, and enhancing the signal-to-noise ratio of the signal, enabling the receiver to more accurately analyze the real satellite signal in a complex signal environment, thereby further improving the reliability of the positioning result.

[0071] Step S2372: Analyze the signal based on the standard signal-to-noise ratio to obtain a real satellite navigation message corresponding to the real satellite signal.

[0072] In this example, by adjusting the coherent integration sign of the real satellite signal according to the change pattern of the telegram bit, a standard signal-to-noise ratio signal greater than the preset signal-to-noise threshold is generated, which solves the problem of the sign change of the integral value caused by the change of the telegram bit sign. This enables the receiver to perform coherent integration over a longer period of time, improves the signal-to-noise ratio of the real satellite signal, and further enhances the analysis accuracy and reliability of the real satellite signal.

[0073] In some examples, the method of predicting the message bit change pattern of the real satellite navigation message based on the pseudo-satellite navigation message in the above-mentioned step S236 may include: predicting the symbol change pattern at the message bit boundary in the real satellite navigation message based on the almanac information in the pseudo-satellite navigation message; and determining the message bit change pattern based on the symbol change pattern at the message bit boundary.

[0074] As shown in the example above, the almanac information contained in the pseudolite signal captured by the receiver shows that the symbol changes in the target satellite's message bit boundaries follow a pattern of "10101010". Based on the almanac information in the pseudolite navigation message, assuming the TOW in the pseudolite signal is 23126 seconds and the WN is 729, the receiver uses this time information to synchronize its local time counter to a time reference point consistent with the satellite system time. Based on the almanac information in the pseudolite navigation message, the receiver analyzes the orbital parameters and time information of the target satellite and predicts that the symbol changes in the real satellite navigation message message bit boundaries also follow a pattern of "10101010", with the symbol flipping every other bit.

[0075] In this example, the almanac information in the pseudo-satellite navigation message is used to predict the symbol change pattern at the message bit boundary in the real satellite navigation message, thereby achieving accurate prediction of the message bit change pattern of the real satellite signal. This provides a more accurate reference basis for the receiver when parsing the real satellite signal, and improves the accuracy and efficiency of signal analysis.

[0076] In other examples, the telegram bit change law includes the correlation law between adjacent telegram bits. Before adjusting the coherent integration symbol of the satellite navigation telegram according to the telegram bit change law of the satellite navigation telegram, the receiver also calculates the statistical probability between historical adjacent telegram bit symbol changes, wherein the statistical probability is used to represent the dependence between adjacent telegram bit symbol changes; the correlation law between adjacent telegram bits is determined according to the statistical probability, and the correlation law is used to represent the probabilistic dependence between the current telegram bit symbol change and the previous telegram bit symbol change; according to the correlation law, the coherent integration symbol of the satellite navigation telegram is dynamically adjusted to eliminate the I / Q path integral value sign change caused by the telegram bit symbol change, so that the signal-to-noise ratio signal of the satellite navigation telegram is greater than the preset signal-to-noise threshold.

[0077] For example, the frame structure of a telegram contains 20 bits per frame, and the start and end bits of each frame are fixed. Based on the time information in the pseudo-satellite signal, the receiver sets the local time counter to be consistent with the time information in the pseudo-satellite signal to obtain a time reference point. The first telegram frame corresponding to the time reference point has a start bit of 0 and an end bit of 19; the second telegram frame has a start bit of 20 and an end bit of 39; and so on. The boundaries of each telegram frame are identified based on the start and end bits of each telegram frame. For example, the message bit boundaries of the first telegram frame are located at bit positions 0 and 19, while the message bit boundaries of the second telegram frame are located at bit positions 20 and 39.

[0078] After determining the message bit boundaries, the receiver further analyzes the message bit variation patterns, specifically the correlation patterns between adjacent message bits. Specifically, the receiver calculates the statistical probabilities between historically adjacent message bit sign changes. These statistical probabilities represent the degree of dependence between adjacent message bit sign changes. This statistical analysis reveals a high degree of dependence between adjacent message bit sign changes, indicating a clear probabilistic dependency between the current message bit sign change and the previous message bit sign change. For example, if the previous bit was "1," the probability of the current bit being "0" is 0.8; if the previous bit was "0," the probability of the current bit being "1" is 0.7. Based on these statistical probabilities, the correlation patterns between adjacent message bits are determined, allowing the receiver to dynamically adjust the coherent integration sign of the satellite navigation message based on these correlation patterns. In other words, at message bit boundaries, the receiver adjusts the coherent integration sign based on the sign variation patterns of the current and previous bits to eliminate sign variations in the I / Q path integral values caused by message bit sign changes.

[0079] In this way, the speed at which the receiver generates a standard signal-to-noise ratio signal can be increased, further improving the efficiency of determining the receiver's position.

[0080] In one implementation, the method for predicting a symbol change pattern at a message bit boundary in a real satellite navigation message based on the almanac information in the pseudolite navigation message may include the following steps S2361 to S2363:

[0081] Step S2361: Synchronize the local time counter using the time information in the pseudolite signal to obtain a time reference point for synchronizing the local time counter with the satellite system time.

[0082] The time information includes the second of the week TOW and the week number WN.

[0083] For example, the time information in the pseudolite signal is TOW = 231261 seconds and WN = 729. After receiving the pseudolite signal, the receiver extracts the time information by parsing the navigation message in the signal. The analysis result shows that the current TOW is 231261 seconds and WN is 729. The receiver then uses the extracted time information (TOW and WN) to adjust the local time counter. Specifically, the receiver sets the local time counter to match the time information in the pseudolite signal. For example, if the local time counter currently has TOW = 23100 seconds and WN = 725, the receiver will adjust the local time counter forward to TOW = 231261 seconds and WN = 729.

[0084] In this way, the receiver obtains a time reference point, which ensures that the receiver can accurately determine the signal timestamp when processing real satellite signals, thereby improving the accuracy and reliability of signal processing.

[0085] Step S2362: Determine the start bit and end bit of each frame of the satellite navigation message based on the obtained time reference point and the navigation message structure of the satellite navigation message.

[0086] Continuing with the above example, after obtaining the time reference point, the receiver determines the start and end bits of each frame based on the structure of the satellite navigation message. Assume that the satellite navigation message frame structure contains 20 bits per frame, and the start and end bits of each frame are fixed. The receiver uses the obtained time reference point and the structure of the navigation message to calculate the start and end bits of each frame. For example, assume that the first frame corresponding to the time reference point has a start bit of 0 and an end bit of 19; the second frame has a start bit of 20 and an end bit of 39; and so on.

[0087] In this way, the receiver can accurately determine the boundaries of each frame of the message, providing accurate frame synchronization information for subsequent signal processing. When processing real satellite signals, it can accurately identify and parse each frame of the message, thereby improving the accuracy and reliability of signal processing.

[0088] Step S2363: Determine the message bit boundary based on the start bit and the end bit.

[0089] Message bit boundaries refer to the start and end positions of each message frame. These positions are key reference points in signal processing. Specifically, the receiver clearly identifies the boundaries of each message frame based on the start and end bits of each message frame.

[0090] Based on the start and end bits of each frame of the message, the receiver further determines the message bit boundaries. For example, the message bit boundaries of the first message frame are located at bit positions 0 and 19, and the message bit boundaries of the second message frame are located at bit positions 20 and 39.

[0091] In this implementation, the receiver uses the time information in the pseudo-satellite signal to synchronize the local time counter, and based on this, determines the message bit boundaries of the real satellite navigation message, realizing the prediction of the change pattern of the message bits of the real satellite signal, providing the receiver with a more accurate signal analysis basis, and further improving the accuracy and efficiency of satellite signal analysis.

[0092] It should be understood that the above numerical values are exemplary descriptions and are not intended to be limiting.

[0093] Figure 3 This is a flow chart of a positioning method provided by an embodiment of the present disclosure. Figure 1 The pseudo-satellite base station 130 in the positioning system shown in FIG. Figure 3 As shown, the method may include steps S310-S320.

[0094] Step S310: Determine the target satellite simulated by the pseudolite base station.

[0095] The target satellite is a satellite that is not visible from the location of the receiver.

[0096] In some examples, the pseudo-satellite base station may include determining a target satellite simulated by the pseudo-satellite base station based on a pseudo-satellite group mapping relationship; wherein the pseudo-satellite group mapping relationship is a mapping relationship between a target satellite and a pseudo-satellite base station preset by the pseudo-satellite base station, or a mapping relationship between a target satellite and a pseudo-satellite base station obtained by the pseudo-satellite base station from a preset server.

[0097] In this way, the compatibility of pseudo-satellites with real satellites is ensured, interference with ordinary receivers is avoided, positioning accuracy and reliability are improved, the receiver adapts to dynamic environmental changes, and the signal is guaranteed to be stable and continuous.

[0098] The optional implementation of determining the pseudolite group mapping relationship in this step may refer to the embodiment of the pseudolite group mapping relationship in the aforementioned step S210, which will not be described in detail here.

[0099] Step S320: Send the pseudolite signal in the simulated target satellite.

[0100] Among them, the pseudo-satellite signal is used by the receiver to parse the pseudo-satellite signal to obtain the pseudo-satellite navigation message of the target satellite, and to parse the real satellite signal sent by the real satellite based on the pseudo-satellite navigation message of the target satellite to obtain the real satellite navigation message of the real satellite; and to determine the position of the receiver based on the real satellite navigation message.

[0101] In this embodiment, pseudo-satellite base stations are used to simulate invisible satellites and send pseudo-satellite signals. This method can expand the signal coverage range and ensure that the receiver can still obtain sufficient signal sources in complex environments (such as urban canyons, tunnels, indoor parking lots, etc.), thereby improving the reliability and continuity of receiver positioning.

[0102] The optional implementation of this step can refer to the embodiments in the aforementioned steps S210-S240, which will not be repeated here.

[0103] Figure 4 is a schematic diagram of the hardware structure of an electronic device according to another embodiment.

[0104] like Figure 4As shown, the electronic device 400 includes a processor 410 and a memory 420, wherein the memory 420 is used to store an executable computer program, and the processor 410 is used to execute a method as any of the above method embodiments under the control of the computer program.

[0105] In some embodiments, the processor 410 can be used to control the overall operation of the electronic device 400. For example, the processor 410 can execute instructions to implement all or part of the steps of the method in any of the foregoing embodiments of the present disclosure, thereby realizing one or more operations such as voice communication, data communication, database operation, display control, component control, multimedia processing, etc., wherein the above-mentioned components may include sensors, cameras, headphones, input and output devices, etc., and the component may be an internal component of the electronic device itself, or an external component connected to the electronic device wirelessly or wired. The above-mentioned multimedia may include one or more of voice, image, video, and text.

[0106] The electronic device 400 may be Figure 1 The receiver in Figure 1 Pseudo-satellite base station in.

[0107] Each module of the above electronic device 400 may be implemented by the processor 410 in this embodiment executing a computer program stored in the memory 410 , or may be implemented by other structures, which is not limited here.

[0108] The present disclosure may be a system, method and / or computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for causing a processor to implement various aspects of the present disclosure.

[0109] An embodiment of the present disclosure further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the method of any of the above method embodiments is implemented.

[0110] A computer-readable storage medium can be a tangible device that can hold and store instructions for use by an instruction execution device. A computer-readable storage medium can be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which instructions are stored, and any suitable combination thereof. As used herein, a computer-readable storage medium is not to be construed as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through an electrical wire.

[0111] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network can include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions to be stored in the computer-readable storage medium in each computing / processing device.

[0112] The computer program instructions for performing the operations of the present 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 such as Smalltalk, C++, and conventional procedural programming languages such as "C" language or similar programming languages. Computer-readable program instructions may be executed entirely on a user's computer, partially on a user's computer, as an independent software package, partially on a user's computer, partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., utilizing an Internet service provider to connect via the Internet). In some embodiments, an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), may be personalized by utilizing the state information of the computer-readable program instructions. The electronic circuit may execute the computer-readable program instructions, thereby realizing various aspects of the present disclosure.

[0113] Various aspects of the present disclosure are described herein with reference to flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present disclosure. It should be understood that each block of the flowcharts and / or block diagrams, and combinations of blocks in the flowcharts and / or block diagrams, can be implemented by computer-readable program instructions.

[0114] 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 device, thereby producing a machine, so that when these instructions are executed by the processor of the computer or other programmable data processing device, a device is generated that implements the functions / actions specified in one or more blocks in the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium, where these instructions cause the computer, programmable data processing device, and / or other device to operate in a specific manner. Thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing various aspects of the functions / actions specified in one or more blocks in the flowchart and / or block diagram.

[0115] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device so that a series of operational steps are performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to implement the functions / actions specified in one or more blocks in the flowchart and / or block diagram.

[0116] The flowcharts and block diagrams in the accompanying drawings show the possible implementation architecture, functions and operations of the systems, methods and computer program products according to multiple embodiments of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, program segment or part of an instruction, and the module, program segment or part of the instruction contains one or more executable instructions for implementing the specified logical function. In some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system that performs the specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions. It is well known to those skilled in the art that implementation by hardware, implementation by software, and implementation by a combination of software and hardware are all equivalent.

[0117] The embodiments of the present disclosure have been described above. The above description is exemplary, not exhaustive, and is 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 terms used herein are selected to best explain the principles of the embodiments, their practical applications, or technical improvements in the marketplace, or to enable other persons skilled in the art to understand the embodiments disclosed herein. The scope of the present disclosure is defined by the appended claims.

Claims

1. A positioning method, characterized in that: Applications in receivers include: receiving a pseudolite signal emitted by a pseudolite base station simulating a target satellite, wherein the target satellite is a satellite that is not visible from the location of the receiver; parsing the pseudolite signal to obtain a pseudolite navigation message of the target satellite; parsing a real satellite signal sent by a real satellite according to the pseudo-satellite navigation message of the target satellite to obtain a real satellite navigation message of the real satellite; The position of the receiver is determined according to the real satellite navigation message.

2. The method according to claim 1, characterized in that The step of parsing a real satellite signal sent by a real satellite according to the pseudo-satellite navigation message of the target satellite to obtain the real satellite navigation message of the real satellite includes: Determine a theoretical pseudorange Doppler reference value and a local clock bias reference value according to the pseudolite navigation message; Determining, based on the theoretical pseudorange Doppler reference value and the local clock bias reference value, a code phase and Doppler frequency range to be searched when parsing the real satellite signal; Based on the code phase and Doppler frequency range, a real satellite signal sent by a real satellite is parsed to obtain a real satellite navigation message of the real satellite.

3. The method according to claim 1, characterized in that The parsing of the real satellite signal sent by the real satellite according to the pseudolite navigation message of the target satellite includes: Predicting a message bit variation pattern of the real satellite navigation message based on the pseudo-satellite navigation message; The real satellite signal is coherently integrated according to the message bit change rule to analyze the real satellite signal and obtain the real satellite navigation message of the real satellite.

4. The method according to claim 3, characterized in that The coherent integration of the real satellite signal according to the message bit change rule to parse the real satellite signal and obtain the real satellite navigation message of the real satellite includes: Adjusting the coherent integration sign of the real satellite signal according to the bit variation rule of the message to generate a standard signal-to-noise ratio signal greater than a preset signal-to-noise threshold; The standard signal-to-noise ratio signal is analyzed to obtain a real satellite navigation message corresponding to the real satellite signal.

5. The method according to claim 4, characterized in that The predicting of a message bit variation rule of the real satellite navigation message based on the pseudo-satellite navigation message includes: predicting, based on the almanac information in the pseudo-satellite navigation message, a symbol change pattern at a message bit boundary in the real satellite navigation message; The message bit change rule is determined according to the symbol change rule at the message bit boundary.

6. The method according to claim 5, characterized in that The step of adjusting the coherent integration sign of the real satellite signal according to the message bit variation rule to generate a standard signal-to-noise ratio signal greater than a preset signal-to-noise threshold comprises: At the message bit boundary, the coherent integration sign of the real satellite signal is adjusted to eliminate the sign change of the in-phase / orthogonal branch integration value caused by the message bit sign change, thereby generating the standard signal-to-noise ratio signal.

7. The method according to claim 5, characterized in that The step of predicting a symbol change pattern at a message bit boundary in a real satellite navigation message based on the almanac information in the pseudo-satellite navigation message includes: Synchronizing a local time counter using time information in the pseudolite signal to obtain a time reference point for synchronizing the local time counter with satellite system time, wherein the time information includes seconds of the week TOW and week number WN; Determining a start bit and an end bit of each frame of the real satellite navigation message according to the obtained time reference point and the navigation message structure of the real satellite navigation message; Determine the message bit boundary according to the start bit and the end bit; The symbol change rule at the bit boundary of the telegram is predicted.

8. A positioning method, characterized in that: Applied to pseudo-satellite base stations, including: Determining a target satellite simulated by the pseudolite base station; wherein the target satellite is a satellite that is not visible at the location of the receiver; Sending a pseudo-satellite signal simulating the target satellite, wherein the pseudo-satellite signal is used by a receiver to parse the pseudo-satellite signal to obtain a pseudo-satellite navigation message of the target satellite; parsing a real satellite signal sent by a real satellite based on the pseudo-satellite navigation message of the target satellite to obtain a real satellite navigation message of the real satellite; and determining the position of the receiver based on the real satellite navigation message.

9. A positioning device, characterized in that: The positioning device includes a memory and a processor, the memory is used to store a computer program; the processor is used to execute the computer program to implement the method according to any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, which implements the method according to any one of claims 1 to 8 when executed by a processor.

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