Satellite signal processing method and device, equipment, storage medium and product

Abstract

The invention provides a satellite signal processing method and device, equipment, a storage medium and a product. The method is applied to terminal equipment, the terminal equipment comprises a satellite radio navigation service (RNSS) receiving unit and a satellite radio determination service (RDSS) receiving unit, and the method comprises the following steps: obtaining local Beidou time based on a satellite signal received by the RNSS receiving unit; according to the corresponding satellite transmission time delay, calculating to obtain total transmission time delay; on the basis of the local Beidou, according to the total transmission time delay, the transmitting time of the target RDSS signal is predicted; performing error analysis on the emission time of the target RDSS signal, and determining corresponding time uncertainty; measurement is carried out through the RNSS receiving unit, Doppler frequency shift between the satellite and the terminal equipment is determined, and corresponding frequency uncertainty is obtained; and receiving the RDSS signal through an RDSS receiving unit according to the transmitting time, the corresponding time uncertainty and the corresponding frequency uncertainty.

Description

Technical Field

[0001] The present application relates to the field of satellite communication and navigation technology, and in particular to a satellite signal processing method, device, equipment, storage medium and product. Background Art

[0002] With the promotion and application of the Beidou satellite navigation system, many domestic mobile phone manufacturers have begun to integrate the short message communication function of the Beidou satellite's Radio Determination Satellite Service (RDSS) into user terminals. However, in the mass consumer field, especially in products such as mobile phones and wearable devices, the power consumption, volume, and cost of chip modules are very high. As a result, due to the influence of size, power consumption, cost, and electromagnetic interference, when the Beidou RDSS user terminal is integrated into consumer terminals such as mobile phones, the received RDSS signal quality is poor, and the performance needs to be improved.

[0003] In the prior art, there are some solutions that use the information obtained from the satellite radio navigation service (RNSS) in the user terminal to speed up the RDSS signal acquisition speed. However, the existing solutions only speed up the acquisition speed and cannot meet the requirements of directly tracking the RDSS signal. The prediction of the RDSS signal transmission time is inaccurate, and the capture sensitivity of the RDSS signal still cannot be improved. Summary of the invention

[0004] The embodiments of the present application provide a satellite signal processing method, apparatus, device, storage medium and product, which can improve the capture sensitivity of RDSS signals.

[0005] In a first aspect, the present application provides a satellite signal processing method, the method being applied to a terminal device, the terminal device comprising a satellite radio navigation service RNSS receiving unit and a satellite radio determination service RDSS receiving unit, the RNSS receiving unit and the RDSS receiving unit using the same clock signal, the method comprising:

[0006] Based on the satellite signal received by the RNSS receiving unit, correct the local clock error to obtain the local Beidou time;

[0007] Calculating a total transmission delay according to the satellite transmission delay corresponding to the positioning mode of the RNSS receiving unit;

[0008] Based on the local BeiDou time, according to the total transmission delay, the transmission time of the target RDSS signal is predicted;

[0009] Performing error analysis on the emission time of the target RDSS signal to determine the corresponding time uncertainty;

[0010] The RNSS receiving unit is used to measure and determine the Doppler frequency shift between the satellite and the terminal device, and obtain the corresponding frequency uncertainty;

[0011] According to the transmission time, and the corresponding time uncertainty and frequency uncertainty, the RDSS signal is received by the RDSS receiving unit.

[0012] In some possible implementations, performing error analysis on the transmission time of the target RDSS signal to determine the corresponding time uncertainty includes:

[0013] Determine, according to the positioning mode of the RNSS receiving unit, a transmission delay error from when the GEO satellite transmits the RDSS signal to when the RDSS receiving unit receives the RDSS signal;

[0014] Determine the propagation delay between the ground central station and the GEO satellite according to the historical data broadcast by the ground central station, and obtain the uplink delay error;

[0015] A corresponding time uncertainty is determined according to the transmission delay error and the uplink delay error.

[0016] In some possible implementations, the RNSS receiving unit and the RDSS receiving unit correspond to different modules respectively, and the total transmission delay is calculated according to the satellite transmission delay corresponding to the positioning mode of the RNSS receiving unit, including:

[0017] Performing time synchronization between the RNSS receiving unit and the RDSS receiving unit according to the local BeiDou time;

[0018] Determining a corresponding satellite transmission delay according to a positioning mode of the RNSS receiving unit;

[0019] Extract the uplink delay value stored in the database;

[0020] Calculate a first transmission delay according to the satellite transmission delay and the uplink delay value;

[0021] The first transmission delay is corrected according to the one-way zero value of the RNSS receiving unit and the one-way reception zero value of the RDSS receiving unit to obtain a total transmission delay.

[0022] In some possible implementations, before determining the corresponding time uncertainty according to the transmission delay error and the uplink delay error, the method further includes:

[0023] determining a time synchronization error between the RNSS receiving unit and the RDSS receiving unit according to a working clock frequency of the RDSS receiving unit;

[0024] According to the preset value, determine the one-way receiving zero value error;

[0025] The determining a corresponding time uncertainty according to the transmission delay error and the uplink delay error includes:

[0026] A corresponding time uncertainty is determined according to the time synchronization error, the one-way receiving zero-value error, the transmission delay error and the uplink delay error.

[0027] In some possible implementations, the step of performing time synchronization between the RNSS receiving unit and the RDSS receiving unit according to the local BeiDou time comprises:

[0028] Using the second pulse of the RNSS receiving unit as a synchronization signal to trigger an external interrupt of the RDSS receiving unit;

[0029] When the local BeiDou is sent to the RDSS receiving unit by the RNSS receiving unit, time synchronization between the RNSS receiving unit and the RDSS receiving unit is completed.

[0030] In some possible implementations, the RNSS receiving unit and the RDSS receiving unit are integrated into the same module, and the total transmission delay is calculated according to the satellite transmission delay corresponding to the positioning mode of the RNSS receiving unit, including:

[0031] Determining a corresponding satellite transmission delay according to a positioning mode of the RNSS receiving unit;

[0032] Extract the uplink delay value stored in the database;

[0033] Calculating a total transmission delay according to the satellite transmission delay and the uplink delay value;

[0034] In some possible implementations, determining the corresponding satellite transmission delay according to the positioning mode of the RNSS receiving unit includes:

[0035] Calculating the ionospheric transmission delay according to the positioning mode of the RNSS receiving unit;

[0036] According to the satellite signal, determining the corresponding satellite signal pseudorange observation, satellite clock error and observation noise of the pseudorange observation;

[0037] The satellite transmission delay is calculated based on the ionospheric transmission delay, the satellite signal pseudorange observation, the satellite clock error and the observation noise of the pseudorange observation.

[0038] In some possible implementations, the calculating the satellite transmission delay based on the ionospheric transmission delay, the satellite signal pseudorange observation, the satellite clock error, and the observation noise of the pseudorange observation includes:

[0039] Calculating the pseudorange of the RDSS signal according to the ionospheric transmission delay, the satellite signal pseudorange observation, the satellite clock error and the observation noise of the pseudorange observation;

[0040] The satellite transmission delay is determined according to the ratio of the pseudorange of the RDSS signal to the speed of light.

[0041] In some possible implementations, calculating the ionospheric transmission delay according to the positioning mode of the RNSS receiving unit includes:

[0042] When the RNSS receiving unit is in single-frequency positioning mode, the ionospheric transmission delay is calculated by presetting an ionospheric delay correction model;

[0043] When the RNSS receiving unit is not in the single-frequency positioning mode, pseudo-range measurements are performed for signals of multiple frequencies of the GEO satellite to obtain corresponding multiple pseudo-range measurement values;

[0044] An ionospheric delay is determined based on the plurality of pseudorange measurements.

[0045] In some possible implementations, the RNSS receiving unit is in dual-frequency mode, the multiple pseudorange measurement values ​​include a first pseudorange measurement value corresponding to the first satellite signal and a second pseudorange measurement value corresponding to the second satellite signal, and determining the ionospheric delay according to the multiple pseudorange measurement values ​​includes:

[0046] Calculating a difference between the first pseudorange measurement value and the second pseudorange measurement value;

[0047] The ionospheric delay ratio is calculated using a first carrier frequency corresponding to the first satellite signal and a second carrier frequency corresponding to the second satellite signal;

[0048] The ionospheric delay is determined according to the difference and the ionospheric delay ratio.

[0049] In a second aspect, the present application provides a satellite signal processing device, the device comprising:

[0050] A correction module, used to correct the local clock error based on the satellite signal received by the RNSS receiving unit to obtain the local Beidou time;

[0051] A calculation module, configured to calculate a total transmission delay according to a satellite transmission delay corresponding to a positioning mode of the RNSS receiving unit;

[0052] A prediction module, configured to predict the transmission time of the target RDSS signal based on the local BeiDou time and the total transmission delay;

[0053] An analysis module, used to perform error analysis on the emission time of the target RDSS signal to determine the corresponding time uncertainty;

[0054] A determination module, configured to measure through the RNSS receiving unit, determine the Doppler frequency shift between the satellite and the terminal device, and obtain a corresponding frequency uncertainty;

[0055] The capture module is used to receive the RDSS signal through the RDSS receiving unit according to the transmission time and the corresponding time uncertainty and frequency uncertainty.

[0056] In a third aspect, the present application provides a satellite signal processing device, the device comprising: a processor, and a memory storing computer program instructions; the processor reads and executes the computer program instructions to implement the satellite signal processing method described above.

[0057] In a fourth aspect, the present application provides a computer-readable storage medium having computer program instructions stored thereon, and the computer program instructions, when executed by a processor, implement the satellite signal processing method as described above.

[0058] In a fifth aspect, the present application provides a computer program product. When instructions in the computer program product are executed by a processor of an electronic device, the electronic device performs the satellite signal processing method described above.

[0059] The satellite signal processing method, device, equipment, storage medium and product provided in the embodiments of the present application use the information provided by the RNSS receiving unit, such as the corrected local Beidou time, the transmission delay in the positioning mode, etc., to accurately predict the transmission time of the RDSS signal, and perform error analysis to determine the time uncertainty and frequency uncertainty. According to this time uncertainty and frequency uncertainty, the transmission time window and transmission frequency window of the RDSS signal can be accurately estimated, which enables the RDSS receiving unit to search and capture signals within a smaller time and frequency range, thereby improving the sensitivity of signal capture. At the same time, accurate transmission time prediction and error analysis also make the tracking process more sensitive and reliable, which can improve the tracking sensitivity of the RDSS signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] The present application can be better understood from the following description of the specific embodiments of the present application in conjunction with the accompanying drawings, in which:

[0061] Other features, objects and advantages of the present application will become more apparent by reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings, in which the same or similar reference numerals represent the same or similar features.

[0062] Figure 1 is a flowchart of a satellite signal processing method provided by an embodiment of the present application;

[0063] Figure 2 is a flowchart of a satellite signal processing method provided by another embodiment of the present application;

[0064] Figure 3 This is a flowchart of a satellite signal processing method for integrating an RNSS chip and an RDSS chip into a terminal device provided by an embodiment of the present application;

[0065] Figure 4 is a flowchart of a satellite signal processing method in which RNSS and RDSS functions are integrated into one chip, provided by an embodiment of the present application;

[0066] Figure 5 is a schematic diagram of the structure of a satellite signal processing device provided by an embodiment of the present application;

[0067] Figure 6 It is a schematic diagram of the hardware structure of the satellite signal processing device provided in the embodiment of the present application. DETAILED DESCRIPTION

[0068] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0069] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0070] Beidou RDSS Regional Short Message Communication System: refers to the active positioning mode of the Beidou satellite navigation system using the Radio Determination Satellite Service (RDSS), which can be used for communication. The Beidou-3 satellite navigation system uses three geostationary Earth Orbit (GEO) satellites to broadcast information to users through the downlink S band. Each GEO satellite broadcasts 7 beams, and a total of 21 beams are broadcast in the service area. However, it is impossible to receive 21 satellite signal beams at the same time at any time and any place; Beidou RDSS users transmit signals to satellites through the uplink L band.

[0071] Downlink outbound beam: also known as downlink satellite signal beam, refers to the Beidou RDSS regional short message communication system, which uses three GEO satellites located at 80 degrees, 110.5 degrees and 140 degrees east longitude to broadcast S-band satellite signals to users on the ground (including within about 1,000 kilometers of the ground). Each GEO satellite broadcasts 7 beam signals, numbered 1 to 7, for a total of 21 beams. Each outbound beam carries system information and user-specific information, which is divided into public information segment and dedicated information segment.

[0072] Response beam: also known as receiving response beam, refers to the Beidou RDSS regional short message communication system. The user terminal must lock the downlink outbound beam of a GEO satellite and synchronize the local time with the time of the downlink outbound beam. When the user terminal sends information, the transmission time should be synchronized with the time of the downlink outbound beam.

[0073] One-way reception zero value: refers to the signal transmission delay from the time the satellite signal reaches the antenna interface of the user terminal, after passing through the low noise amplifier (LNA), down conversion, A / D conversion and other processes, the user terminal recognizes the reference time information of the satellite signal.

[0074] In order to solve the problems of the prior art, the embodiments of the present application provide a satellite signal processing method, device, equipment, storage medium and product. The satellite signal processing method provided by the embodiments of the present application is first introduced below.

[0075] Figure 1 The flowchart of a satellite signal processing method provided by an embodiment of the present application is shown. The above method is applied to a terminal device, wherein the above terminal device includes a satellite radio navigation service RNSS receiving unit and a satellite radio determination service RDSS receiving unit, and the above RNSS receiving unit and the above RDSS receiving unit use the same clock signal, such as Figure 1 As shown, the method includes the following steps: S101 to S106.

[0076] S101: Based on the satellite signal received by the RNSS receiving unit, correct the local clock error to obtain the local Beidou time.

[0077] In the specific implementation, the RNSS receiving unit must first determine the error (i.e. clock difference) of the local device clock through the received satellite signal (such as the satellite signal of the Beidou system). The information carried by the satellite signal includes the exact time of the satellite (provided by the satellite's own clock). The receiving unit can use the difference between the arrival time of the satellite signal and the local clock to perform time correction. The common correction method is to correct the local clock in real time through techniques such as least squares method or Kalman filtering to make it closer to the satellite time, and finally obtain the local Beidou time.

[0078] S102: Calculate the total transmission delay according to the satellite transmission delay corresponding to the positioning mode of the RNSS receiving unit.

[0079] In a specific implementation, the time delay of satellite signal transmission is determined by the propagation time of the signal from the satellite to the receiving unit, which is usually related to the distance between the satellite and the receiving device (i.e., the propagation path). The receiving unit calculates the transmission delay of the satellite signal based on the satellite's positioning mode (such as the GNSS positioning mode). Specifically, the propagation delay is calculated by measuring the propagation time of the received signal, that is, the distance from the satellite to the receiving unit divided by the speed of light. The receiving unit obtains the satellite clock error and the position of the satellite, and combines it with the position of the local device to deduce the total delay of the signal.

[0080] S103: Based on the local BeiDou time and the total transmission delay, the transmission time of the target RDSS signal is predicted.

[0081] In the specific implementation, assuming that the reception time of the RDSS signal is known, the transmission time is obtained by reverse calculation using the propagation delay of the satellite signal and the time corrected by the local clock. This involves synchronization algorithms and time calculation, and the algorithms that may be used include delay estimation, reverse propagation and other methods.

[0082] S104: Perform error analysis on the emission time of the target RDSS signal to determine the corresponding time uncertainty.

[0083] In the specific implementation, since various factors in measurement and prediction may introduce errors (such as multipath effects in the satellite signal propagation path, atmospheric refraction, etc.), it is necessary to perform error analysis on the launch time. Through the error model, the satellite clock difference, propagation delay estimation error, etc. are analyzed to determine the time uncertainty introduced by these errors.

[0084] As another implementation of S104, the error is analyzed and evaluated by a Kalman filter or Bayesian inference. The time uncertainty is obtained by calculating the influence of various error sources on the time prediction, and finally a time accuracy range (eg, millisecond or microsecond error range) is given.

[0085] S105: Performing measurement through the RNSS receiving unit to determine the Doppler frequency shift between the satellite and the terminal device, and obtaining a corresponding frequency uncertainty.

[0086] In practice, the Doppler shift is caused by the relative motion between the satellite and the receiving device. When the satellite approaches the receiving device, the signal frequency increases (blue shift), and when the satellite moves away from the receiving device, the signal frequency decreases (red shift). The RNSS receiving unit performs frequency analysis on the signal, measures and calculates the Doppler shift. Then, the frequency uncertainty, i.e. the accuracy of the measured frequency, is calculated based on the frequency shift.

[0087] As another implementation of S105, the receiving unit analyzes the received satellite signal, detects the frequency change, and estimates the Doppler frequency using a frequency shift formula.

[0088] S106: Receive the RDSS signal through the RDSS receiving unit according to the transmitting time, and the corresponding time uncertainty and frequency uncertainty.

[0089] In a specific implementation, based on the predicted RDSS signal transmission time and the calculated time uncertainty and frequency uncertainty of the transmission time, the RDSS receiving unit will adjust its receiving strategy according to these uncertainties to improve the accuracy of signal reception and minimize the errors caused by time and frequency errors. Finally, the receiving unit will receive the RDSS signal and perform further processing.

[0090] As another implementation of S106, the received RDSS signal may be filtered, time synchronized, and frequency corrected to ensure that the received signal is within a predetermined time and frequency range and to eliminate interference caused by errors as much as possible.

[0091] The satellite signal processing method provided in the embodiment of the present application uses the information provided by the RNSS receiving unit, such as the corrected local Beidou time, the transmission delay in the positioning mode, etc., to accurately predict the transmission time of the RDSS signal, and perform error analysis to determine the time uncertainty and frequency uncertainty. According to this time uncertainty and frequency uncertainty, the transmission time window and transmission frequency window of the RDSS signal can be accurately estimated, which enables the RDSS receiving unit to search and capture signals within a smaller time and frequency range, thereby improving the sensitivity of signal capture. At the same time, accurate transmission time prediction and error analysis also make the tracking process more sensitive and reliable, which can improve the tracking sensitivity of the RDSS signal.

[0092] In order to ensure the accuracy of the satellite navigation system in time synchronization, in some implementations, the above S104 may include the following steps: S1041 to S1043.

[0093] S1041: Determine, according to the positioning mode of the RNSS receiving unit, a transmission delay error from when the GEO satellite transmits the RDSS signal to when the RDSS receiving unit receives the RDSS signal.

[0094] In a specific implementation, the specific position of the GEO satellite is determined according to the positioning mode of the RNSS receiving unit (e.g., satellite positioning mode, different signal sources, etc.). The position of the satellite can be calculated using its orbital data or real-time orbital data. According to the position of the receiving unit, the distance between the satellite and the receiving unit is calculated, and the theoretical transmission delay is calculated using the speed of light. The actual signal reception time recorded by the receiving unit is compared with the theoretical transmission delay to determine the actual delay error. Error analysis is based on the difference between the received signal and the theoretical value. Multiple measurements can be used for statistical analysis to detect and predict delay error patterns. Common sources of error include atmospheric effects (such as ionospheric delay, tropospheric delay), multipath effects (such as reflected signals), etc. These errors are compensated and corrected through models. The delay error is dynamically corrected by using algorithms such as Kalman filters or least squares methods, future error trends are predicted, and transmission delay error values ​​are output.

[0095] S1042: Determine the propagation delay between the ground central station and the GEO satellite based on the historical data broadcast by the ground central station, and obtain the uplink delay error.

[0096] In the specific implementation, historical data is obtained from the data source broadcast by the ground central station. This data usually includes information such as the relative position and propagation speed between the ground central station and the satellite. These historical data are parsed and used for subsequent calculations. Based on the historical data, the theoretical propagation delay from the ground central station to the GEO satellite is calculated, and the uplink delay error is obtained by comparing the actual recorded propagation delay with the theoretical delay. The uplink delay error is combined with the historical data to adjust the time synchronization.

[0097] S1043: Determine a corresponding time uncertainty according to the transmission delay error and the uplink delay error.

[0098] In a specific implementation, the transmission delay error and the uplink delay error calculated in S1041 and S1042 are combined to merge multiple error sources and obtain a comprehensive time uncertainty.

[0099] In a specific implementation, the estimation of time uncertainty can be further optimized through filtering algorithms (such as Kalman filtering). By fusing the results of multiple signal transmissions, the accuracy of time prediction is further improved to obtain a comprehensive time uncertainty.

[0100] The above implementation of the embodiment of the present application realizes the calculation and correction of time error by acquiring historical data, real-time signals, error models and filtering algorithms. By dynamically correcting the transmission delay error and uplink delay error, combined with the comprehensive error calculation, the time uncertainty of the system is finally obtained, ensuring the accuracy of the satellite navigation system in time synchronization.

[0101] In order to provide high-precision time synchronization and positioning services in complex environments, in some implementations, the RNSS receiving unit and the RDSS receiving unit correspond to different modules respectively, and the S102 may include the following steps: S1021 to S1025.

[0102] S1021: According to the local BeiDou clock, the RNSS receiving unit and the RDSS receiving unit are synchronized.

[0103] In the specific implementation, the current Beidou standard time is first obtained by receiving signals from Beidou satellites. The Beidou system broadcasts its precise timestamp, and the receiving unit can synchronize the local clock by decoding the time information in the signal. For each receiving unit (RNSS and RDSS receiving unit), the local clock is calibrated.

[0104] S1022: Determine the corresponding satellite transmission delay according to the positioning mode of the RNSS receiving unit.

[0105] In the specific implementation, the positioning mode of the RNSS receiving unit is first parsed. This usually includes the location of the receiving unit, the received satellite signal, and the orbital information of the target satellite. According to the positioning mode of the receiving unit, the distance between the satellite and the receiving unit is calculated. According to the distance between the satellite and the receiving unit, the propagation delay of the satellite signal is calculated. When calculating the delay, corrections for factors such as the ionosphere and troposphere can be added, and appropriate models can be used to consider the impact of the atmosphere on the signal. The impact of multipath propagation also needs to be corrected through multiple sampling and filtering.

[0106] S1023: Extract the uplink delay value stored in the database.

[0107] In a specific implementation, the saved uplink delay value is accessed through a database interface. The uplink delay data is the historical measurement data of the ground central station, and is usually calculated based on the actual transmission path between the ground central station and the satellite.

[0108] S1024: Calculate a first transmission delay based on the satellite transmission delay and the uplink delay value.

[0109] In a specific implementation, the satellite transmission delay obtained from step S1022 is added to the uplink delay extracted from step S1023 to obtain a first transmission delay. The errors of the two delay values ​​are further corrected. For example, the delay error can be optimized by using a Kalman filter or other filtering algorithms to reduce the influence of factors such as the atmosphere and device clock errors.

[0110] S1025: According to the one-way zero value of the RNSS receiving unit and the one-way reception zero value of the RDSS receiving unit, correct the first transmission delay to obtain a total transmission delay.

[0111] In a specific implementation, the one-way zero value of the RNSS receiving unit indicates the time error of the signal arrival measured by the RNSS receiving unit. The one-way receiving zero value of the RDSS receiving unit indicates the time error when the RDSS receiving unit receives the signal. The two zero values ​​are used to correct the first transmission delay to obtain the total transmission delay.

[0112] The above implementation of the embodiment of the present application first realizes the time synchronization of the RNSS receiving unit and the RDSS receiving unit, then calculates the first transmission delay based on the satellite transmission delay and uplink delay data, and finally calculates the total transmission delay by correcting the zero value. Each step involves accurate delay calculation and error correction to ensure that the system can provide high-precision time synchronization and positioning services in complex environments.

[0113] In order to ensure the accuracy of the results, in some embodiments, before the above S1043, the above method may further include the following steps: S10431 to S10432.

[0114] S10431: Determine the time synchronization error between the RNSS receiving unit and the RDSS receiving unit according to the working clock frequency of the RDSS receiving unit.

[0115] In a specific implementation, the working clock frequency of the RDSS receiving unit is obtained, and the frequency is compared with the clock frequency of the RNSS receiving unit, and the synchronization error is calculated using the clock frequency difference.

[0116] S10432: Determine the one-way receiving zero value error according to a preset value.

[0117] In the specific implementation, you first need to get a preset value, which may be read from a configuration file, hardware initialization, or system settings. The preset value is usually a known value set by the system or designer in the early stage, which may represent a reference error under some ideal state to determine the one-way receiving zero value error.

[0118] The above S1043 includes:

[0119] The corresponding time uncertainty is determined according to the time synchronization error, the one-way receiving zero value error, the transmission delay error and the uplink delay error.

[0120] In the specific implementation, in addition to the time synchronization error and the one-way receiving zero value error, the transmission delay error and the uplink delay error need to be obtained. These delay values ​​are obtained from the system, and the errors from these different sources are synthesized. The synthesis method usually determines the total uncertainty by weighted average, sum of squares, etc. of the errors. If these errors are independent and follow a normal distribution, the standard error propagation formula can be used for synthesis to determine the corresponding time uncertainty.

[0121] The above implementation of the embodiment of the present application first extracts the necessary clock frequency and error data from the hardware and configuration, and then calculates and synthesizes the error through mathematical formulas to finally obtain a total time uncertainty. This process usually involves real-time data acquisition, dynamic error correction, and complex mathematical processing, and each calculation step is accurately performed according to the actual needs of the system to ensure the accuracy of the results and the efficient operation of the system.

[0122] In order to achieve accurate synchronization of the two receiving units, in some implementations, the above S1021 may include the following steps: S10211 to S10212.

[0123] S10211: Using the second pulse of the above-mentioned RNSS receiving unit as a synchronization signal to trigger an external interrupt of the above-mentioned RDSS receiving unit.

[0124] In the specific implementation, it is first necessary to confirm whether the RNSS receiving unit can accurately generate a second pulse signal. The second pulse is usually a timing signal that changes periodically every second. By configuring the RNSS receiving unit, ensure that the second pulse signal it outputs can be used to synchronize the RDSS receiving unit. Usually, this requires configuring the output port or clock signal interface of the RNSS receiving unit. Set the second pulse output of the RNSS receiving unit to ensure that the RDSS receiving unit can receive the trigger signal when each second pulse arrives. The RDSS receiving unit needs to have an external interrupt function. An external interrupt usually means that when an external event (such as the arrival of a second pulse signal) occurs, the system can immediately respond and interrupt the current program execution, and execute the code related to the event instead. Once the second pulse signal triggers an external interrupt, the RDSS receiving unit begins to perform the corresponding synchronization operation, such as recording a timestamp, adjusting the local clock, or starting other synchronization processes.

[0125] S10212: When the local BeiDou signal is sent to the RDSS receiving unit via the RNSS receiving unit, the time synchronization between the RNSS receiving unit and the RDSS receiving unit is completed.

[0126] In the specific implementation, the local BeiDou time is obtained, and then the time is passed to the RDSS receiving unit through the communication mechanism. The time data is packaged and sent to the RDSS receiving unit through the specified protocol. When the RDSS receives the local BeiDou time sent by the RNSS, it adjusts its internal clock to complete the time synchronization between the RNSS receiving unit and the RDSS receiving unit.

[0127] The above implementation of the embodiment of the present application reads the pulse-per-second signal of the RNSS receiving unit and uses the signal as a trigger signal to start the external interrupt of the RDSS receiving unit to ensure the synchronization between the RDSS and the RNSS, and then sends the local Beidou time to the RDSS receiving unit through the RNSS receiving unit to ensure the time synchronization between the two, and handles the reception, analysis, transmission and synchronization process of the time signal to ensure that the system maintains high precision during the entire synchronization process. The above scheme uses the interrupt mechanism and communication protocol of the precise control hardware to ensure that the time information can be accurately transmitted and synchronized to achieve precise synchronization of the two receiving units.

[0128] In order to ensure that the total transmission delay can accurately reflect the overall delay of signal propagation, in some implementations, reference may be made to Figure 2 The RNSS receiving unit and the RDSS receiving unit are integrated into the same module. The S102 may include the following steps: 201 to 203.

[0129] 201: Determine the corresponding satellite transmission delay according to the positioning mode of the RNSS receiving unit.

[0130] In the specific implementation, it is first necessary to identify the current positioning mode of the RNSS receiving unit. Once the positioning mode is determined, the signal propagation delay is estimated based on the satellite's orbital parameters. Based on the satellite's orbital information and the receiving conditions under the positioning mode, the software will use a propagation model (such as a free space propagation model) to calculate the propagation delay of the satellite signal.

[0131] 202: Retrieve the uplink delay value stored in the database.

[0132] In the specific implementation, the uplink delay refers to the propagation delay of the signal from the ground central station to the satellite. This delay is related to the propagation path, frequency, weather and other factors of the signal from the ground to the satellite. In order to obtain the uplink delay, it is necessary to query the previously stored delay database and extract the uplink delay value stored in the database.

[0133] 203: Calculate the total transmission delay according to the satellite transmission delay and the uplink delay value.

[0134] In a specific implementation, the satellite transmission delay from step 201 and the uplink delay value extracted in step 202 are received. At this time, the satellite transmission delay generally reflects the signal propagation time from the satellite to the receiving unit, while the uplink delay is the signal propagation time from the ground center station to the satellite. Then, the total transmission delay is calculated according to a preset formula.

[0135] The above implementation of the embodiment of the present application calculates the satellite transmission delay according to the positioning mode of the receiving unit, combined with the satellite orbit and signal propagation model. This process depends on the positioning mode and the specific location data of the satellite, and then extracts the uplink delay value from the database. Usually, the historical delay data related to signal propagation is obtained by querying the database, and necessary verification is performed, and then the satellite transmission delay is added to the uplink delay to obtain the total transmission delay. This calculation result provides a basis for the subsequent improvement of signal transmission, synchronization and positioning accuracy. Through precise calculation and data extraction, it ensures that the total transmission delay can accurately reflect the overall delay of signal propagation.

[0136] In order to ensure accurate calculation of satellite transmission delay, in some embodiments, determining the corresponding satellite transmission delay according to the positioning mode of the RNSS receiving unit may include the following steps: S2011 to S2013.

[0137] S2011: Calculate the ionospheric transmission delay according to the positioning mode of the above-mentioned RNSS receiving unit.

[0138] In the specific implementation, first, determine the current positioning mode of the RNSS receiving unit, and then use the corresponding method to calculate the ionospheric transmission delay according to the different positioning modes. In the specific calculation, when the satellite signal passes through the earth's ionosphere, the presence of charged particles in the ionosphere will slow down the signal propagation speed. If the receiving unit uses a dual-frequency GNSS receiver, the ionospheric delay can be differentiated by two signals of different frequencies to eliminate the ionospheric effect and obtain a more accurate delay value. The delay caused by the ionosphere is calculated from the positioning mode of the receiving unit and the current GNSS signal frequency parameters.

[0139] S2012: According to the satellite signal, determine the corresponding satellite signal pseudo-range observation quantity, satellite clock error and observation noise of the pseudo-range observation quantity.

[0140] In the specific implementation, the pseudorange is an estimate of the distance from the receiving unit to the satellite. Because the actual distance between the receiving unit and the satellite cannot be measured directly, the pseudorange observation estimates the distance by measuring the delay of satellite signal propagation. The pseudorange can be estimated by measuring the satellite signal propagation delay and combining it with the satellite's orbital data (i.e., the satellite's position and velocity). The satellite clock error refers to the error between the atomic clock on the satellite and the ground standard time. The satellite clock error is calculated using the ephemeris and satellite clock correction parameters. In order to accurately process the pseudorange observation, it is necessary to estimate the noise of the pseudorange observation based on the received signal quality, environmental factors (such as weather, building obstruction, etc.), and the system noise model.

[0141] S2013: Calculate the satellite transmission delay based on the ionospheric transmission delay, the satellite signal pseudorange observation, the satellite clock error and the observation noise of the pseudorange observation.

[0142] In the specific implementation, the ionospheric transmission delay is obtained from S2011, and the pseudorange observation, satellite clock error and observation noise are obtained from S2012. All these parameters will be used as inputs to correct the delay by comprehensively using the ionospheric delay, pseudorange observation, satellite clock error and noise. The correction process usually uses optimization algorithms such as least squares or Kalman filtering to minimize the delay deviation caused by the error and calculate the satellite transmission delay.

[0143] The above implementation method of the embodiment of the present application calculates the ionospheric transmission delay, estimates it based on the positioning mode, GNSS frequency and ionospheric parameters, and then extracts pseudorange observations, satellite clock errors and noise from the satellite signals, considers signal propagation errors and environmental factors, combines the above information, and uses an optimization algorithm to comprehensively calculate the final satellite transmission delay, ensuring high delay accuracy and adapting to different positioning modes, thereby ensuring accurate calculation of satellite transmission delays.

[0144] In order to ensure accurate positioning and delay estimation, in some implementations, the above S2013 may include the following steps: S20131 to S20132.

[0145] S20131: Calculate the pseudorange of the RDSS signal based on the ionospheric transmission delay, the satellite signal pseudorange observation, the satellite clock error and the observation noise of the pseudorange observation.

[0146] In a specific implementation, the pseudorange of the RDSS signal is calculated based on the ionospheric transmission delay, the satellite signal pseudorange observation, the satellite clock error and the observation noise of the pseudorange observation.

[0147] S20132: Determine the satellite transmission delay based on the ratio of the pseudorange of the RDSS signal to the speed of light.

[0148] In a specific implementation, the ratio of the pseudorange of the RDSS signal to the speed of light is calculated to determine the satellite transmission delay.

[0149] The above implementation of the embodiment of the present application calculates the pseudorange of the RDSS signal based on the input ionospheric transmission delay, satellite signal pseudorange observation, satellite clock error, noise and other factors. This involves modeling and compensating these errors to obtain accurate pseudoranges, and then directly calculating the satellite's transmission delay based on the calculated pseudorange and the ratio with the speed of light. Due to various errors in the satellite signal transmission process, the calculation of the delay also needs to be dynamically corrected according to the actual situation to ensure the accuracy of the final result, so as to ensure accurate delay estimation.

[0150] In order to accurately calculate and correct the ionospheric delay, in some embodiments, the above S2011 may include the following steps: S20111 to S20113.

[0151] S20111: When the RNSS receiving unit is in single-frequency positioning mode, the ionospheric transmission delay is calculated by using a preset ionospheric delay correction model.

[0152] In specific implementations, compensation for ionospheric delay usually relies on preset ionospheric delay correction models, which estimate ionospheric delay based on factors such as the signal propagation path (relative position between satellite and receiver) and time (season, geographic location). According to these model preset parameters, such as: the geographic location of the receiver, the orbital information of the satellite, the propagation path and altitude of the satellite signal, etc., are input into the model. The model gives the impact of ionospheric delay on the signal, and the ionospheric delay can be calculated based on the model. The model is used to calculate the ionospheric delay and output the calculation results. This value is the propagation time delay of the ionosphere to the signal, so the ionospheric transmission delay is calculated.

[0153] S20112: When the RNSS receiving unit is not in the single-frequency positioning mode, pseudo-range measurements are performed for signals of multiple frequencies of the GEO satellite to obtain corresponding multiple pseudo-range measurement values.

[0154] In a specific implementation, the receiver receives signals of different frequencies from multiple satellites. For example, commonly used frequencies include the L1 band (B1I signal, 1561.098MHz) and the L2 band (B3I signal, 1268.52MHz). For GEO satellites, the receiver usually uses at least two signals of different frequencies (for example, L1 and L2) for positioning calculations. For each received frequency signal, the receiver measures its propagation time and calculates the pseudorange based on the propagation time. In multi-frequency positioning mode, the receiver obtains pseudorange measurement values ​​of multiple different frequencies and obtains corresponding multiple pseudorange measurement values.

[0155] S20113: Determine the ionospheric delay based on the above multiple pseudorange measurement values.

[0156] In the specific implementation, since the ionospheric delay has different effects on signals of different frequencies, the receiver can use a dual-frequency pseudorange combination to eliminate the impact of ionospheric delay. Assuming that there are pseudorange measurements of L1 and L2 frequencies, the estimated value of ionospheric delay can be calculated based on the dual-frequency pseudorange combination. For multi-frequency signals, the receiver will perform similar calculations and combine the pseudorange data of multiple frequency signals to further optimize the estimation of ionospheric delay. Then the ionospheric delay is determined.

[0157] The above implementation methods of the embodiments of the present application ensure that in different positioning modes (single frequency and multi-frequency), the receiver can accurately calculate and correct the ionospheric delay based on methods such as ionospheric model, pseudorange measurement and dual-frequency combination.

[0158] In order to accurately determine the ionospheric delay, in some embodiments, the RNSS receiving unit is in dual-frequency mode, the multiple pseudorange measurement values ​​include a first pseudorange measurement value corresponding to the first satellite signal and a second pseudorange measurement value corresponding to the second satellite signal, and S20113 may include the following steps: S201131 to S201133.

[0159] S201131: Calculate the difference between the first pseudorange measurement value and the second pseudorange measurement value.

[0160] In a specific implementation, in a satellite navigation system, pseudo-range measurement refers to estimating the distance between the receiver and the satellite by receiving the propagation time of the satellite signal. The dual-frequency mode uses two signals of different frequencies for measurement, thereby reducing the impact of ionospheric delay and calculating their difference.

[0161] S201132: Calculate an ionospheric delay ratio using a first carrier frequency corresponding to the first satellite signal and a second carrier frequency corresponding to the second satellite signal.

[0162] In a specific implementation, ionospheric delay is caused by free electrons in the ionosphere, which affects the propagation speed of satellite signals through the ionosphere. Signals of different frequencies are affected by the ionosphere to different degrees, so the influence of the ionosphere can be estimated by dual-frequency measurement. The ratio of ionospheric delay is the ratio of the influence of the ionosphere on two frequency signals during propagation, and is usually calculated using carrier frequencies of different frequencies. According to the first carrier frequency corresponding to the above-mentioned first satellite signal and the second carrier frequency corresponding to the above-mentioned second satellite signal, the ionospheric delay ratio is calculated by the ratio.

[0163] S201133: Determine the ionospheric delay based on the above difference and the above ionospheric delay ratio.

[0164] In a specific implementation, the absolute value of the ionospheric delay is derived through a preset formula using the known pseudorange difference and ionospheric delay ratio, and the actual value of the ionospheric delay is obtained through reverse deduction to determine the ionospheric delay.

[0165] The above implementation method of the embodiment of the present application obtains the pseudorange measurement values ​​of different frequency signals of the same satellite, calculates their difference, calculates the ionospheric delay ratio according to the carrier frequency of two (or more) different frequency signals of the satellite, and then uses the pseudorange difference and the ionospheric delay ratio to infer the specific delay of the ionosphere, thereby accurately determining the ionospheric delay.

[0166] As another implementation method, based on the Beidou satellite navigation system, when the Beidou RNSS chip and the Beidou RDSS chip are respectively integrated into the terminal device, refer to Figure 3 The method includes the following steps: S301 to S310. First, it is necessary to ensure that the clocks of the RF front end and the baseband signal processing module of the two chips are the same, that is, the same clock source is used. S301: The integrated terminal is turned on and initialized.

[0167] S302: The RNSS receiver effectively locates and corrects the local clock error to obtain accurate local Beidou time. In this case, when using the Beidou RNSS chip for positioning, it is necessary to use the B1I signal containing the Beidou system L1 frequency band for PVT solution. After effective positioning, the local clock error of the RNSS receiver is corrected using the PVT solution result to obtain the local BDT. In order to guide and capture the Beidou RDSS downlink beam, Beidou time must be used when synchronizing with the Beidou RDSS chip. After the RNSS receiver is effectively located, the local clock error is corrected to obtain the local BDT, that is, t u,RNSS,BDT, or t u,RNSS .

[0168] S303: The RDSS user terminal in the integrated terminal is synchronized with the RNSS receiver time. After the Beidou RNSS receiver effectively locates and corrects the local clock error, it adjusts the second leading edge of the local PPS pulse output to align it with the whole second of the Beidou time, and uses the PPS output pulse of the Beidou RNSS chip as a synchronization signal to trigger the external interrupt of the Beidou RDSS chip. At the same time, the Beidou time (BDT) corresponding to the PPS signal is sent to the Beidou RDSS chip, so that the local time of the RDSS chip is also synchronized with the BDT. Then, in the application terminal that integrates the Beidou RDSS and RNSS chips, the local time of the Beidou RNSS receiver is consistent with the Beidou RDSS user terminal, and is synchronized with the system time (that is, Beidou time). In other words, t u,RDSS =t u,RNSS =t BDT .

[0169] S304: According to the positioning mode of the RNSS receiver, calculate the transmission delay of the RDSS signal from the satellite antenna surface to the RDSS user terminal antenna surface. Since the RNSS receiver uses the B1I signal including the Beidou system for positioning, the Beidou GEO satellite is searched from the B1I signal that has been tracked. If the B1I signal on the three GEO satellites can be tracked, it means that the current GEO satellite is a visible star, and the RDSS downlink beam of the Beidou GEO satellite can be guided to capture. If the B1I signal of the Beidou GEO satellite is not found, it means that there is no visible GEO satellite at present, or the current GEO satellite signal is too weak and unusable. The pseudo-range calculation formula of the B1I signal of the tracked GEO satellite is as follows:

[0170]

[0171] Among them, ρ B1I is the pseudorange of the B1I signal, r B1I is the true distance between the GEO satellite and the RNSS receiver, δt u,RNSS is the local clock error of the RNSS receiver, is the satellite clock error of the B1I signal on the GEO satellite, I B1I is the ionospheric delay of the B1I signal, T B1I is the tropospheric delay of the B1I signal, ε ρ,B1I is the pseudorange measurement error of the B1I signal of the RNSS receiver, and c is the speed of light in vacuum.

[0172] The RDSS payload of the BeiDou system is on a GEO satellite. The GEO satellite broadcasts both the B1I navigation signal and the BeiDou RDSS downlink beam signal. It can be assumed that the receiver has tracked the B1I signal of the GEO satellite and can also receive the RDSS downlink beam of the GEO satellite. Assuming its pseudorange ρ RDSS , and its calculation formula is as follows:

[0173] ρ RDSS =r RDSS +c(δt u,RDSS )+I RDSS +T RDSS

[0174] Among them, r RDSS is the true distance between the GEO satellite and the RDSS receiver, δt u,RDSS is the local clock error of the RDSS receiver, I RDSS is the ionospheric delay of the RDSS signal, T RDSS is the tropospheric delay of the RDSS signal.

[0175] Since the RNSS receiver and the RDSS user terminal are integrated into the same user terminal, they receive the B1I navigation signal and the RDSS downlink beam signal from the GEO satellite respectively. RDSS =r B1I .

[0176] When the radio signal passes through the ionosphere, a time delay will occur. Since the ionosphere is a diffuse medium related to the frequency of electromagnetic waves, according to the inverse relationship between the ionospheric time delay and the square of the carrier frequency, the ionospheric time delay I of the B1I signal and the RDSS signal mentioned above is obtained. B1I and I RDSS The functional relationship is shown as follows:

[0177]

[0178] Among them, f B1I is the nominal carrier frequency of the B1I signal, which is 1561.098MHz; f RDSS is the nominal carrier frequency of the RDSS signal, which is 2491.75MHz.

[0179] Since the RNSS receiver and the RDSS user terminal are integrated into the same user terminal and use the same clock source, the local clock error is a common error relative to BeiDou time, and the two are the same, that is: δt u,RDSS =δt u,RNSSSince the troposphere is a non-dispersive medium, the propagation delay of electromagnetic waves in the troposphere has nothing to do with its frequency, but only with the relative position of the satellite and the receiver. Therefore, when the same terminal receives the signal from the same GEO satellite, its tropospheric delay is equal, that is, T RDSS =T B1I .

[0180] Furthermore, through the above three formulas, the following formula can be derived:

[0181]

[0182]

[0183] Among them, ρ B1I It is the pseudo-range observation of the B1I signal of the GEO satellite that has been obtained by the RNSS receiver. is the clock error of the GEO satellite, and the correction value can be obtained from the ephemeris parameters of the B1I signal. Since the GEO satellite is stationary relative to the earth, the earth rotation error term can be ignored. ρ,B1I is the observation noise of the pseudo-range observation of the B1I signal, which is normally distributed with a mean of 0 and a variance of This variance is usually called the variance of the user range error (URE), which will bring a certain time uncertainty to the subsequent high-sensitivity capture of the RDSS signal.

[0184] Therefore, the transmission delay of the RDSS signal of the GEO satellite from the satellite antenna surface to the RDSS user terminal antenna surface is t su,delay As shown in the following formula, the subscript su represents the propagation from the satellite to the user terminal.

[0185]

[0186] S305: Calculate the total transmission delay of the RDSS signal from the ground central station transmitting antenna surface to the corresponding GEO satellite, converted by the GEO satellite, and then from the GEO satellite antenna surface to the RDSS user terminal antenna surface.

[0187] Since the RNSS receiver has been effectively positioned, the standard deviation of the three-dimensional spatial positioning error σ can be obtained statistically P , the spatial position precision factor (Position Dilution of Precision, PDOP) can also be obtained in the PVT solution, then the standard deviation σ of the pseudorange observation noise of the B1I signal can be obtained according to the following formula: URE .

[0188]

[0189] Among them, I B1I is the ionospheric transmission delay of the B1I signal of the GEO satellite.

[0190] According to the positioning mode of the RNSS receiver, there are two specific cases, for dual-frequency (or multi-frequency) positioning mode. For example: a dual-frequency positioning mode in which Beidou B1I and B2I signals or B3I signals are used. Since Beidou GEO satellites broadcast B1I, B2I, and B3I navigation signals, but not B1C, B2a, and B2b; in addition, the Beidou system still broadcasts B1I and B3I navigation signals, and the B2I signal may be replaced by the B2a signal, so the dual-frequency or multi-frequency positioning mode in which B1I and B3I participate can be used.

[0191] After the RNSS receiver tracks the BeiDou GEO satellite, the pseudo-range measurement values ​​of the B1I and B3I signals of the GEO satellite can be obtained, as shown in the following formula:

[0192]

[0193] In the above formula, since it is the pseudo-range measurement value of the B1I and B3I signals transmitted by the receiver at the same time to the same GEO satellite, the geometric distance r between the satellite and the receiver and the local clock error δt u,RNSS , satellite clock error and Tropospheric delay T B1I and T B3I are all common errors, and after subtracting the observation noise of the same GEO satellite at the same time, they can be ignored. and There is also a difference of on-board equipment delay, but since its uncertainty is less than 1 nanosecond, it can also be ignored, that is:

[0194] Furthermore, we can get the following formula:

[0195] I B1I -I B3I ≈ρ B1I -ρ B3I

[0196] And I B1I and I B3I is the ionospheric delay of the RNSS receiver receiving B1I and B3I of the same GEO satellite, and the following formula can be obtained:

[0197]

[0198] Among them, f B1I is the nominal carrier frequency of the B1I signal, which is 1561.098MHz; f B3Iis the nominal carrier frequency of the B3I signal, which is 1268.52MHz.

[0199] Thus, I can be obtained by the following formula: B1I :

[0200] I B1I ≈1.945×(ρ B3I -ρ B1I )

[0201] According to the obtained value, calculate the transmission delay t of the RDSS signal from the satellite antenna surface to the RDSS user terminal antenna surface su,delay .

[0202] If the RNSS receiver adopts the single-frequency positioning mode, the ionospheric delay correction model provided by the BeiDou satellite navigation system is used to correct the ionospheric delay of the B1I signal of the GEO satellite to obtain I B1I The value of the transmission delay t can also be obtained by substituting the obtained values ​​into su,delay .

[0203] For the GNSS system, the time when the satellite's navigation signal is transmitted is the moment when the signal leaves the satellite antenna surface. This moment is determined by the satellite's onboard time. The difference between the time when the ground receiver receives the signal and the time when the signal is transmitted is the signal transmission time. Of course, the transmission time contains many errors. Multiplying the transmission time by the speed of light in a vacuum is the pseudorange. For the RDSS system, the RDSS payload on the satellite is a transparent forwarding function, so the time reference of the Beidou RDSS downlink beam does not come from the GEO satellite, but from the ground center station. The downlink beam signal received by the ground user terminal has a transmission path from the ground center station uplink to the GEO satellite, and then downlink from the GEO satellite to the ground user terminal. For the entire Beidou system, the Beidou RNSS system and the Beidou RDSS system are synchronized, that is, at a certain BDT time, when the RNSS navigation signal leaves the satellite antenna surface, the Beidou time represented by the pseudocode phase is the same as the Beidou time represented by the pseudocode phase when the Beidou RDSS downlink beam signal leaves the transmitting antenna surface of the ground center station.

[0204] Therefore, when the Beidou RNSS receiver receives the B1I signal from the GEO satellite, the launch time obtained is the moment when the B1I signal leaves the GEO satellite antenna surface; and when the Beidou RDSS user terminal receives the RDSS signal from the GEO satellite, the launch time obtained is the moment when the RDSS signal leaves the transmitting antenna surface of the ground center station. The two are different. The transmission delay of the Beidou RDSS signal also includes the propagation delay from the ground center station antenna to the corresponding GEO satellite (including the ionosphere and troposphere delays in the uplink path, as well as the one-way zero value of the signal sending and receiving station and the one-way zero value of the satellite transponder).

[0205] Use t cs,delay Represents the transmission delay, and its subscript cs represents the propagation from the ground central station to the GEO satellite. In the outbound broadcast information of the Beidou RDSS system, it is broadcast to various ground user machines in real time and cyclically as the "uplink delay value of the delay parameter". Since the transmission delay is a slow variable, it can be saved in the Beidou RDSS user machine and extracted from the flash memory after startup. After tracking the downlink beam of the RDSS system, the "uplink delay value of the delay parameter" is extracted from the outbound broadcast information to update the historical data in the flash memory. After the Beidou RDSS user machine is synchronized with the Beidou RNSS receiver, the transmission delay t of the RDSS signal from the satellite antenna surface to the RDSS user machine antenna surface is obtained. su,delay , then the total transmission delay of the current RDSS downlink beam is:

[0206] t all,delay =t cs,delay +t su,delay

[0207] S306: Perform zero value correction on the total transmission delay of the RDSS signal.

[0208] After the RNSS receiver locates the application terminal that integrates the Beidou RDSS and RNSS chips, the local time of the Beidou RNSS receiver and the Beidou RDSS user terminal are synchronized through time synchronization, and the local time is consistent with the Beidou time. However, since two different chips are used and different RF channels are used, the total transmission delay t of the RDSS signal needs to be calculated by using the unidirectional reception zero value of the RDSS chip and the unidirectional zero value of the RNSS chip. all,delay Perform zero value correction.

[0209] The one-way reception zero value of the Beidou RNSS receiver and the Beidou RDSS user terminal refers to the signal transmission delay from the time the satellite signal reaches the receiver antenna interface to the time the receiver identifies the reference time mark information of the satellite signal.

[0210] Assume that the one-way zero value of the BeiDou RNSS receiver is t sz,RNSS ; The one-way receiving zero value of Beidou RDSS user terminal is t sz,RDSS These two values ​​are inherent characteristics of the device and are written into the flash memory before the device leaves the factory. For the devices in the same batch, the difference of the one-way zero values ​​between them is in the nanosecond level, which can be ignored. The two one-way zero values ​​can be considered as fixed values. Therefore, the total transmission delay of the RDSS signal after zero value correction is as follows:

[0211] t all,delay =t cs,delay +t su,delay +t sz,RDSS -tsz,RNSS

[0212] S307: Using Beidou time as the local system time, predict the transmission time of the current RDSS signal.

[0213] After the Beidou RNSS receiver effectively locates and corrects the local clock error, and synchronizes with the Beidou RDSS user terminal, the local time of the Beidou RDSS user terminal is the current Beidou time, that is: t u,RDSS =t u,RNSS =t BDT Therefore, the current time at which the GEO satellite downlink beam signal is transmitted is As shown below:

[0214]

[0215] According to the transmission time, the local pseudo code generator of the Beidou RDSS user terminal can generate a pseudo code sequence that is consistent with the pseudo code phase of the currently received RDSS signal, so that the local pseudo code is correlated with the received pseudo code, and the correlation peak is obtained after accumulation operation, and the code phase of the received signal is tracked and locked.

[0216] S308: Perform error analysis on the predicted emission time of the RDSS signal.

[0217] After obtaining the launch time of the current Beidou RDSS signal, in order to use the tracking engine in the RDSS chip to capture the downlink beam signal of the RDSS, it is also necessary to determine the uncertainty of the launch time, that is, the various error factors introduced in the process of calculating the launch time. The main errors introduced are as follows:

[0218] The Beidou RNSS receiver is used to correct the local clock error and synchronize the time with the Beidou RDSS user terminal. According to the timing accuracy of the Beidou RNSS receiver, it can generally reach 20ns; the two chips are synchronized through external interrupts, and the error is affected by the CPU working clock of the RDSS chip. If the CPU working clock is 300MHz, the error is within 3.3ns. The transmission delay t from the GEO satellite transmitting the RDSS signal to the Beidou RDSS user terminal receiving the signal su,delay , including ionospheric delay correction error and Beidou RNSS receiver observation noise. For ionospheric delay correction error, if dual-frequency (or multi-frequency) positioning mode is used, the error is about 1 meter, so the time error introduced is about 3ns; if single-frequency positioning mode is used, the ionospheric delay correction model provided by the Beidou system is used for correction, and the error is about 5 meters, so the time error introduced is about 15ns. Since the RNSS receiver has been effectively positioned, the standard deviation of the three-dimensional spatial positioning error σ can be statistically obtained P, the spatial position precision factor (Position Dilution of Precision, PDOP) can also be obtained in the PVT solution, and the standard deviation σ of the pseudorange observation noise of the B1I signal can be obtained URE .

[0219] The standard deviation of the three-dimensional spatial positioning error of the single-point PVT solution σ P , its value is about 8 meters. Even if a single Beidou B1I signal is used for positioning, the number of visible satellites can reach 15, so the spatial position precision factor PDOP is generally between 1 and 2. Therefore, the distance measurement error introduced by the observation noise of the Beidou RNSS receiver is as follows. Divided by the speed of light c in a vacuum, the introduced time error is within 27ns.

[0220]

[0221] The propagation delay from the ground central station antenna to the corresponding GEO satellite (including the ionosphere and troposphere delays in the uplink path, as well as the outbound one-way zero value of the signal reception and transmission and the one-way zero value of the satellite transponder) is broadcast by the Beidou RDSS system's outbound broadcast message, and its error is at the ns level. At the same time, the method of the present invention uses its historical data, and its error is within 20ns. Therefore, the total error can be limited to within 30ns. The error introduced by the one-way reception zero value correction of the Beidou RNSS receiver and the Beidou RDSS user terminal. For the same batch of products, the factory fixed value written into the flash memory is used. There is always a difference between this value and the specific chip module, and the error caused by this difference is about 10ns.

[0222] In summary, for the predicted emission time of the RDSS signal, even if the RNSS receiver uses single-frequency positioning, the total time uncertainty is Within 105.3ns, as shown below:

[0223]

[0224] If a certain margin is left, the uncertainty of the RDSS signal transmission time can be controlled within 200ns. The pseudo code rate of the Beidou RDSS signal is 8.16Mcps, the pseudo code cycle length is 8160chips, and the tracking channel of the Beidou RDSS chip tracking engine can reach a dozen chips. Therefore, from the perspective of the time domain, the tracking channel of the tracking engine can be used to capture the RDSS signal.

[0225] S309: Correct the Doppler frequency of the RDSS signal.

[0226] After determining the transmission time and time uncertainty of the RDSS signal, in order to use the tracking engine of the RDSS chip to capture and track the RDSS downlink beam signal, it is also necessary to determine the current Doppler frequency of the signal.

[0227] Since the Beidou RNSS receiver is used for effective positioning first, the Doppler frequency shift f between the current GEO satellite and the local device can be measured. d,RNSS , and transmit this value to the BeiDou RDSS user terminal. Then the Doppler frequency shift f between the RDSS signal broadcast by the GEO satellite and the local device can be calculated using the following formula: d,RDSS .

[0228]

[0229] Among them, f B1I is the nominal carrier frequency of the B1I signal, which is 1561.098MHz; f RDSS is the nominal carrier frequency of the RDSS signal, which is 2491.75MHz.

[0230] Since the clocks of the RF front-end and baseband signal processing modules of the two chips are shared when integrated into the terminal equipment, that is, the same clock source is used, so when the Beidou RNSS receiver is effectively positioned, the local clock difference and clock drift can be obtained through PVT solution. It can be considered that when the Beidou RDSS user terminal uses the Doppler frequency, the Doppler frequency uncertainty has been eliminated. Through Doppler frequency correction, when the Beidou RDSS user terminal uses the tracking engine to capture and track the RDSS downlink beam signal, generally 1 to 2 tracking channel resources can meet the frequency traction range requirements of the tracking engine frequency locking loop.

[0231] S310: Use the tracking engine of the user terminal to guide and capture the RDSS signal.

[0232] The pseudo code generator of the tracking engine of the Beidou RDSS chip is used to generate a pseudo code sequence of the current code phase, which is correlated and coherently integrated with the downlink beam signal of the GEO satellite received by the Beidou RDSS chip, and the downlink beam signal is tracked by the tracking loop to achieve bit synchronization and frame synchronization.

[0233] Since the pseudo code phase information, Doppler shift and Doppler frequency uncertainty of the GEO satellite are known, a longer coherent integration time can be used (this integration time is much longer than the integration time of the capture engine), and one or more tracking channels can be used to track the satellite signal based on the Doppler frequency uncertainty, thereby greatly improving the capture and tracking sensitivity of the Beidou RDSS system downlink beam signal.

[0234] When the BeiDou RNSS and RDSS functions are integrated into one SOC chip, the BeiDou RDSS and RNSS modules can use the same clock source. The time synchronization and zero value correction steps between the RDSS user terminal and the RNSS receiver can be omitted. In the error analysis of the predicted RDSS signal transmission time, the error introduced by the time synchronization of the two chips through external interrupts can be omitted.

[0235] Therefore, when the BeiDou RNSS and RDSS functions are integrated into one SOC chip, the total time uncertainty of the predicted RDSS signal emission time is Within 92ns, as shown below:

[0236]

[0237] On this basis, we can refer to Figure 4 , the specific execution steps include: S401 to S408.

[0238] S401: The terminal using the SOC chip is turned on and initialized.

[0239] S402: The RNSS receiver effectively locates and corrects the local clock error to obtain accurate local Beidou time.

[0240] S403: According to the positioning mode of the RNSS receiver, the transmission delay of the RDSS signal from the satellite antenna plane to the RDSS user terminal antenna plane is calculated.

[0241] S404: Calculate the total transmission delay of the RDSS signal from the ground central station transmitting antenna surface to the corresponding GEO satellite, converted by the GEO satellite, and then from the GEO satellite antenna surface to the RDSS user terminal antenna surface.

[0242] S405: Using Beidou time as the local system time, predict the transmission time of the current RDSS signal.

[0243] S406: Perform error analysis on the predicted emission time of the RDSS signal.

[0244] S407: Correct the Doppler frequency of the RDSS signal.

[0245] S408: Use the tracking engine of the user terminal to guide and capture the RDSS signal.

[0246] Through the above steps, the capture and tracking sensitivity of Beidou RDSS signals has been greatly improved. If the Beidou RDSS and RNSS functions are integrated into a SOC chip, the hardware resources of the Beidou RDSS signal capture engine can be omitted, and the existing tracking channel resources in the RNSS receiver can be directly reused, which greatly reduces the hardware resources of the chip, reduces costs and power consumption, improves integration, and promotes the promotion and application of the Beidou RDSS system in the mass consumer field.

[0247] Based on the satellite signal processing method provided in the above embodiment, the present application also provides a specific implementation of a satellite signal processing device. Please refer to the following embodiment.

[0248] See first Figure 5 The satellite signal processing device 500 provided in the embodiment of the present application includes the following modules:

[0249] The correction module 501 is used to correct the local clock error based on the satellite signal received by the above-mentioned RNSS receiving unit to obtain the local Beidou time.

[0250] The calculation module 502 is used to calculate the total transmission delay according to the satellite transmission delay corresponding to the positioning mode of the RNSS receiving unit.

[0251] The prediction module 503 is used to predict the transmission time of the target RDSS signal based on the local Beidou time and the total transmission delay.

[0252] The analysis module 504 is used to perform error analysis on the emission time of the target RDSS signal to determine the corresponding time uncertainty.

[0253] The determination module 505 is used to perform measurement through the above-mentioned RNSS receiving unit to determine the Doppler frequency shift between the GEO satellite and the terminal device, and obtain the corresponding frequency uncertainty.

[0254] The capture module 506 is used to receive the RDSS signal through the RDSS receiving unit according to the transmission time, and the corresponding time uncertainty and frequency uncertainty.

[0255] The satellite signal processing device provided in the embodiment of the present application uses the information provided by the RNSS receiving unit, such as the corrected local Beidou time, the transmission delay in the positioning mode, etc., to accurately predict the transmission time of the RDSS signal, and perform error analysis to determine the time uncertainty and frequency uncertainty. According to this time uncertainty and frequency uncertainty, the transmission time window and transmission frequency window of the RDSS signal can be accurately estimated, which enables the RDSS receiving unit to search and capture signals within a smaller time and frequency range, thereby improving the sensitivity of signal capture. At the same time, accurate transmission time prediction and error analysis also make the tracking process more sensitive and reliable, which can improve the tracking sensitivity of the RDSS signal.

[0256] As an implementation of the present application, the analysis module 504 includes:

[0257] The determination unit is used to determine the transmission delay error from the GEO satellite transmitting the RDSS signal to the RDSS receiving unit receiving the RDSS signal according to the positioning mode of the RNSS receiving unit.

[0258] The determination unit is also used to determine the propagation delay between the above-mentioned ground central station and the GEO satellite according to the historical data broadcast by the ground central station, and obtain the uplink delay error.

[0259] The determination unit is further used to determine the corresponding time uncertainty according to the above transmission delay error and the above uplink delay error.

[0260] As an implementation of the present application, the calculation module 502 includes:

[0261] A synchronization unit is used to synchronize the time of the RNSS receiving unit and the RDSS receiving unit according to the local BeiDou time.

[0262] The determination unit is used to determine the corresponding satellite transmission delay according to the positioning mode of the above-mentioned RNSS receiving unit.

[0263] The extraction unit is used to extract the uplink delay value stored in the database.

[0264] The calculation unit is used to calculate the first transmission delay according to the satellite transmission delay and the uplink delay value.

[0265] The correction unit is used to correct the first transmission delay according to the one-way zero value of the RNSS receiving unit and the one-way reception zero value of the RDSS receiving unit to obtain the total transmission delay.

[0266] As an implementation of the present application, the satellite signal processing device 500 further includes:

[0267] The determination module is used to determine the time synchronization error between the RNSS receiving unit and the RDSS receiving unit according to the working clock frequency of the RDSS receiving unit.

[0268] The determination module is also used to determine the one-way receiving zero value error according to a preset value.

[0269] Identify units, including:

[0270] The determination subunit is used to determine the corresponding time uncertainty according to the above-mentioned time synchronization error, the above-mentioned one-way receiving zero value error, the above-mentioned transmission delay error and the above-mentioned uplink delay error.

[0271] As an implementation of the present application, the synchronization unit includes:

[0272] The trigger subunit is used to use the second pulse of the above-mentioned RNSS receiving unit as a synchronization signal to trigger the external interrupt of the above-mentioned RDSS receiving unit.

[0273] The sending subunit is used to complete the time synchronization between the RNSS receiving unit and the RDSS receiving unit when sending the local BeiDou to the RDSS receiving unit through the RNSS receiving unit.

[0274] As an implementation of the present application, the calculation module 502 includes:

[0275] The determination unit is used to determine the corresponding satellite transmission delay according to the positioning mode of the above-mentioned RNSS receiving unit.

[0276] The extraction unit is used to extract the uplink delay value stored in the database.

[0277] The calculation unit is used to calculate the total transmission delay according to the satellite transmission delay and the uplink delay value.

[0278] As an implementation of the present application, the determining unit includes:

[0279] The calculation subunit is used to calculate the ionospheric transmission delay according to the positioning mode of the above-mentioned RNSS receiving unit.

[0280] The determination subunit is used to determine the corresponding satellite signal pseudorange observation quantity, satellite clock error and observation noise of the pseudorange observation quantity according to the above satellite signal.

[0281] The calculation subunit is further used to calculate the satellite transmission delay based on the above-mentioned ionospheric transmission delay, the above-mentioned satellite signal pseudorange observation, the above-mentioned satellite clock error and the observation noise of the above-mentioned pseudorange observation.

[0282] As an implementation of the present application, the computing subunit includes:

[0283] The calculation subunit is used to calculate the pseudorange of the RDSS signal according to the above-mentioned ionospheric transmission delay, the above-mentioned satellite signal pseudorange observation, the above-mentioned satellite clock error and the observation noise of the above-mentioned pseudorange observation.

[0284] The determination subunit is used to determine the satellite transmission delay according to the ratio of the pseudorange of the RDSS signal to the speed of light.

[0285] As an implementation of the present application, the computing subunit includes:

[0286] The calculation subunit is used to calculate the ionospheric transmission delay by using a preset ionospheric delay correction model when the above-mentioned RNSS receiving unit is in single-frequency positioning mode.

[0287] The measurement subunit is used to perform pseudo-range measurements on multiple signals of different frequencies of GEO satellites respectively to obtain corresponding multiple pseudo-range measurement values ​​when the RNSS receiving unit is not in single-frequency positioning mode.

[0288] The determination subunit is used to determine the ionospheric delay according to the above-mentioned multiple pseudorange measurement values.

[0289] As an implementation of the present application, determining a subunit includes:

[0290] The calculation subunit is used to calculate the difference between the first pseudorange measurement value and the second pseudorange measurement value.

[0291] The calculation subunit is further used to calculate the first carrier frequency corresponding to the first satellite signal and the second carrier frequency corresponding to the second satellite signal to obtain the ionospheric delay ratio.

[0292] A determination subunit is used to determine the ionospheric delay according to the difference and the ionospheric delay ratio.

[0293] Each module in the satellite signal processing device provided in the embodiment of the present application can implement each step in the above-mentioned satellite signal processing method and achieve corresponding effects, which will not be described in detail here for the sake of brevity.

[0294] Figure 6 A schematic diagram of the structure of the satellite signal processing hardware provided in an embodiment of the present application is shown.

[0295] The satellite signal processing device may include a processor 601 and a memory 602 storing computer program instructions.

[0296] Specifically, the processor 601 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0297] The memory 602 may include a large capacity memory for data or instructions. By way of example and not limitation, the memory 602 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. In appropriate cases, the memory 602 may include a removable or non-removable (or fixed) medium. In appropriate cases, the memory 602 may be inside or outside the integrated gateway disaster recovery device. In a specific embodiment, the memory 602 is a non-volatile solid-state memory.

[0298] The memory may include a read-only memory (ROM), a random access memory (RAM), a magnetic disk storage medium device, an optical storage medium device, a flash memory device, an electrical, optical or other physical / tangible memory storage device. Therefore, generally, the memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., a memory device) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the satellite signal processing method according to any one embodiment of the present disclosure.

[0299] The processor 601 implements any one of the satellite signal processing methods in the above embodiments by reading and executing computer program instructions stored in the memory 602 .

[0300] In one example, the satellite signal processing device may further include a communication interface 603 and a bus 610. Figure 6 As shown, the processor 601, the memory 602, and the communication interface 603 are connected via a bus 610 and communicate with each other.

[0301] The communication interface 603 is mainly used to implement communication between various modules, devices, units and / or equipment in the embodiments of the present application.

[0302] Bus 610 includes hardware, software or both, and the parts of online data flow billing equipment are coupled to each other. For example, but not limitation, bus may include accelerated graphics port (AGP) or other graphics bus, enhanced industrial standard architecture (EISA) bus, front-end bus (FSB), hypertransport (HT) interconnection, industrial standard architecture (ISA) bus, infinite bandwidth interconnection, low pin count (LPC) bus, memory bus, micro channel architecture (MCA) bus, peripheral component interconnection (PCI) bus, PCI-Express (PCI-X) bus, serial advanced technology attachment (SATA) bus, video electronics standard association local (VLB) bus or other suitable bus or two or more of these combinations. In appropriate cases, bus 610 may include one or more buses. Although the present application embodiment describes and shows a specific bus, the present application considers any suitable bus or interconnection.

[0303] In addition, in combination with the satellite signal processing method in the above embodiment, the embodiment of the present application can provide a computer storage medium for implementation. The computer storage medium stores computer program instructions; when the computer program instructions are executed by the processor, any satellite signal processing method in the above embodiment is implemented.

[0304] An embodiment of the present application also provides a computer program product, including a computer program, and when the computer program is processed and executed, it implements any one of the satellite signal processing methods in the above embodiments.

[0305] It should be clear that the present application is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present application is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application.

[0306] The functional blocks shown in the above-described block diagram can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present application are programs or code segments that are used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link by a data signal carried in a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0307] It should also be noted that the exemplary embodiments mentioned in this application describe some methods or systems based on a series of steps or devices. However, this application is not limited to the order of the above steps, that is, the steps can be performed in the order mentioned in the embodiment, or in a different order from the embodiment, or several steps can be performed simultaneously.

[0308] Aspects of the present disclosure are described above with reference to the flowchart and / or block diagram of the method, device (system) and computer program product according to the embodiment of the present disclosure. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine so that these instructions executed by the processor of the computer or other programmable data processing device enable the implementation of the function / action specified in one or more boxes of the flowchart and / or block diagram. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field programmable logic circuit. It can also be understood that each box in the block diagram and / or flowchart and the combination of boxes in the block diagram and / or flowchart can also be implemented by dedicated hardware that performs a specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions.

[0309] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A satellite signal processing method, characterized in that: The method is applied to a terminal device, wherein the terminal device includes a satellite radio navigation service RNSS receiving unit and a satellite radio determination service RDSS receiving unit, wherein the RNSS receiving unit and the RDSS receiving unit use the same clock signal, and the method includes: Based on the satellite signal received by the RNSS receiving unit, correct the local clock error to obtain the local Beidou time; Calculating a total transmission delay according to the satellite transmission delay corresponding to the positioning mode of the RNSS receiving unit; Based on the local BeiDou time, according to the total transmission delay, the transmission time of the target RDSS signal is predicted; Performing error analysis on the emission time of the target RDSS signal to determine the corresponding time uncertainty; The RNSS receiving unit is used to measure and determine the Doppler frequency shift between the satellite and the terminal device, and obtain the corresponding frequency uncertainty; According to the transmission time, and the corresponding time uncertainty and frequency uncertainty, the RDSS signal is received by the RDSS receiving unit.

2. The satellite signal processing method according to claim 1, characterized in that: The performing error analysis on the emission time of the target RDSS signal to determine the corresponding time uncertainty includes: Determine, according to the positioning mode of the RNSS receiving unit, a transmission delay error from when the GEO satellite transmits the RDSS signal to when the RDSS receiving unit receives the RDSS signal; Determine the propagation delay between the ground central station and the GEO satellite according to the historical data broadcast by the ground central station, and obtain the uplink delay error; A corresponding time uncertainty is determined according to the transmission delay error and the uplink delay error.

3. The satellite signal processing method according to claim 2, characterized in that: The RNSS receiving unit and the RDSS receiving unit correspond to different modules respectively, and the total transmission delay is calculated according to the satellite transmission delay corresponding to the positioning mode of the RNSS receiving unit, including: Performing time synchronization between the RNSS receiving unit and the RDSS receiving unit according to the local BeiDou time; Determining a corresponding satellite transmission delay according to a positioning mode of the RNSS receiving unit; Extract the uplink delay value stored in the database; Calculate a first transmission delay according to the satellite transmission delay and the uplink delay value; The first transmission delay is corrected according to the one-way zero value of the RNSS receiving unit and the one-way reception zero value of the RDSS receiving unit to obtain a total transmission delay.

4. The satellite signal processing method according to claim 3, characterized in that: Before determining the corresponding time uncertainty according to the transmission delay error and the uplink delay error, the method further includes: determining a time synchronization error between the RNSS receiving unit and the RDSS receiving unit according to a working clock frequency of the RDSS receiving unit; According to the preset value, determine the one-way receiving zero value error; The determining a corresponding time uncertainty according to the transmission delay error and the uplink delay error includes: A corresponding time uncertainty is determined according to the time synchronization error, the one-way reception zero-value error, the transmission delay error and the uplink delay error.

5. The satellite signal processing method according to claim 3, characterized in that: The step of performing time synchronization between the RNSS receiving unit and the RDSS receiving unit according to the local BeiDou time comprises: Using the second pulse of the RNSS receiving unit as a synchronization signal to trigger an external interrupt of the RDSS receiving unit; When the local BeiDou is sent to the RDSS receiving unit by the RNSS receiving unit, time synchronization between the RNSS receiving unit and the RDSS receiving unit is completed.

6. The satellite signal processing method according to claim 1, characterized in that: The RNSS receiving unit and the RDSS receiving unit are integrated into the same module, and the total transmission delay is calculated according to the satellite transmission delay corresponding to the positioning mode of the RNSS receiving unit, including: Determining a corresponding satellite transmission delay according to a positioning mode of the RNSS receiving unit; Extract the uplink delay value stored in the database; The total transmission delay is calculated based on the satellite transmission delay and the uplink delay value.

7. The satellite signal processing method according to any one of claims 3 to 6, characterized in that: The determining, according to the positioning mode of the RNSS receiving unit, the corresponding satellite transmission delay comprises: Calculating the ionospheric transmission delay according to the positioning mode of the RNSS receiving unit; According to the satellite signal, determining the corresponding satellite signal pseudorange observation, satellite clock error and observation noise of the pseudorange observation; The satellite transmission delay is calculated based on the ionospheric transmission delay, the satellite signal pseudorange observation, the satellite clock error and the observation noise of the pseudorange observation.

8. The satellite signal processing method according to claim 7, characterized in that: The calculating the satellite transmission delay based on the ionospheric transmission delay, the satellite signal pseudorange observation, the satellite clock error and the observation noise of the pseudorange observation comprises: Calculating the pseudorange of the RDSS signal according to the ionospheric transmission delay, the satellite signal pseudorange observation, the satellite clock error and the observation noise of the pseudorange observation; The satellite transmission delay is determined according to the ratio of the pseudorange of the RDSS signal to the speed of light.

9. The satellite signal processing method according to claim 7, characterized in that: The calculating the ionospheric transmission delay according to the positioning mode of the RNSS receiving unit includes: When the RNSS receiving unit is in single-frequency positioning mode, the ionospheric transmission delay is calculated by presetting an ionospheric delay correction model; When the RNSS receiving unit is not in the single-frequency positioning mode, pseudo-range measurements are performed for signals of multiple frequencies of the GEO satellite to obtain corresponding multiple pseudo-range measurement values; An ionospheric delay is determined based on the plurality of pseudorange measurements.

10. The satellite signal processing method according to claim 9, characterized in that: The RNSS receiving unit is in dual-frequency mode, the multiple pseudo-range measurement values ​​include a first pseudo-range measurement value corresponding to a first satellite signal and a second pseudo-range measurement value corresponding to a second satellite signal, and determining the ionospheric delay according to the multiple pseudo-range measurement values ​​includes: Calculating a difference between the first pseudorange measurement value and the second pseudorange measurement value; The ionospheric delay ratio is calculated using a first carrier frequency corresponding to the first satellite signal and a second carrier frequency corresponding to the second satellite signal; The ionospheric delay is determined according to the difference and the ionospheric delay ratio.

11. A satellite signal processing device, characterized in that: The device comprises: A correction module is used to correct the local clock error based on the satellite signal received by the RNSS receiving unit to obtain the local Beidou time; A calculation module, configured to calculate a total transmission delay according to a satellite transmission delay corresponding to a positioning mode of the RNSS receiving unit; A prediction module, configured to predict the transmission time of the target RDSS signal based on the local BeiDou time and the total transmission delay; An analysis module, used to perform error analysis on the emission time of the target RDSS signal to determine the corresponding time uncertainty; A determination module, configured to measure through the RNSS receiving unit, determine the Doppler frequency shift between the satellite and the terminal device, and obtain a corresponding frequency uncertainty; The capture module is used to receive the RDSS signal through the RDSS receiving unit according to the transmission time and the corresponding time uncertainty and frequency uncertainty.

12. A satellite signal processing device, characterized in that: The device comprises: a processor and a memory storing computer program instructions; the processor reads and executes the computer program instructions to implement the satellite signal processing method according to any one of claims 1-10.

13. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed by a processor, the satellite signal processing method according to any one of claims 1 to 10 is implemented.

14. A computer program product, characterized in that When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device executes the satellite signal processing method as described in any one of claims 1 to 10.

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