Single-station three-frequency cycle slip detection and repair method, product, medium and equipment

Abstract

The invention discloses a single-station three-frequency cycle slip detection and restoration method, a product, a medium and equipment, and relates to the technical field of GNSS data processing, and the method comprises the steps: obtaining inertial data and a three-frequency carrier phase observation value; based on the three-frequency carrier phase observation value, adopting an STPIR algorithm to obtain an STPIR cycle slip decision quantity; on the basis of the inertial data and the three-frequency carrier phase observation value, determining a satellite-ground pseudo-range through Kalman filtering time updating and in combination with a precise ephemeris; constructing an ultra-wide lane phase combination observation value according to the satellite and earth pseudo-range, and obtaining an ultra-wide lane phase combination cycle slip decision quantity; constructing a cycle slip separation equation based on the STPIR cycle slip decision quantity and the ultra-wide lane phase combination cycle slip decision quantity; and solving the cycle slip separation equation to obtain a cycle slip estimation value and repairing the cycle slip estimation value. According to the single-station three-frequency cycle slip detection and repair method, the product, the medium and the equipment disclosed by the invention, the accuracy and the efficiency of single-station three-frequency cycle slip detection and repair can be effectively improved.

Description

Technical Field

[0001] The present application relates to the field of GNSS data processing technology, and in particular to a single-station triple-frequency cycle slip detection and repair method, product, medium and equipment. Background Art

[0002] At present, mainstream global navigation satellite systems (GNSS) have begun to broadcast three or more frequency signals, such as the Global Positioning System (GPS), BeiDou Navigation Satellite System (BDS) and Galileo Satellite Navigation System (Galileo). Triple-frequency carrier phase observation is gradually being used in the fields of transportation, meteorology and agriculture. GNSS is an indispensable key technology for navigation and positioning of pedestrians and vehicles, among which the application prospect of Precise Point Positioning (PPP) technology based on a single-station receiver is even broader. However, in scenarios where obstacles are severely blocked, satellite signals are interrupted due to receiver or satellite failures, and the signal-to-noise ratio of satellite signals reaching the receiver is low, the observation values ​​used by PPP often have cycle slips.

[0003] Accurate cycle slip detection and repair are conducive to PPP convergence and ensure positioning accuracy. Since the linear combination of three-frequency carrier phase observations has the characteristics of long wavelength, low noise and weak ionospheric delay, the three-frequency carrier phase observations can be used to further improve the cycle slip detection accuracy and fuzzy fixed speed. However, most of the existing cycle slip detection algorithms are suitable for dual-frequency phase observations. With the popularization of micro-electro-mechanical system (MEMS) inertial units, some geodetic GNSS receivers have built-in lightweight inertial units. Research on how to use rich inertial data to assist GNSS to achieve accurate cycle slip detection and repair is of great significance to improving the reliability of PPP positioning and promoting related industrial applications.

[0004] The existing cycle slip processing strategies have the following main problems: (1) The cycle slip processing method of only detecting but not repairing causes the single-station PPP to be constantly initialized when encountering a cycle slip, which affects the fuzzy fixed speed and fixation rate to a certain extent; (2) The accuracy of the cycle slip decision quantity of the traditional ionosphere residual (Phase Ionosphere Residual, PIR) decreases when the ionosphere is active, and the detection effect is poor; (3) Most inertial navigation system (INS)-assisted GNSS cycle slip detection methods are only for real-time dynamic carrier phase differential technology (Real-Time Kinematic, RTK), and require two GNSS receivers to work together, which is obviously not suitable for single-station PPP technology. Summary of the invention

[0005] The purpose of this application is to provide a single-station triple-frequency cycle slip detection and repair method, product, medium and equipment, which can effectively improve the accuracy and efficiency of single-station triple-frequency cycle slip detection and repair.

[0006] To achieve the above objectives, this application provides the following solutions:

[0007] In a first aspect, the present application provides a single-station triple-frequency cycle slip detection and repair method, comprising:

[0008] Acquire inertial data and triple-frequency carrier phase observation values; the triple-frequency carrier phase observation values ​​include L1 frequency carrier phase observation values, L2 frequency carrier phase observation values, and L3 frequency carrier phase observation values;

[0009] Based on the three-frequency carrier phase observations, the STPIR algorithm is used to obtain the STPIR cycle slip decision value;

[0010] Based on inertial data and triple-frequency carrier phase observations, the satellite-to-earth pseudorange is determined by Kalman filter time update and precise ephemeris.

[0011] The ultra-wide lane phase combination observation value is constructed according to the satellite-to-earth pseudorange to obtain the ultra-wide lane phase combination cycle slip decision value;

[0012] The cycle slip separation equation is constructed based on the STPIR cycle slip decision quantifier and the ultra-wide lane phase combination cycle slip decision quantifier.

[0013] Solve the cycle slip separation equation to obtain the cycle slip estimate and perform repair.

[0014] Optionally, the acquiring of inertial data and triple-frequency carrier phase observation values ​​specifically includes:

[0015] The inertial navigation system and the single-station GNSS receiver are made to work simultaneously, and the angular velocity and acceleration data are collected as inertial data through the gyroscope and accelerometer in the inertial navigation system, and the triple-frequency carrier phase observation values ​​are collected through the single-station GNSS receiver.

[0016] Optionally, the step of obtaining an STPIR cycle slip decision amount based on the three-frequency carrier phase observation value by using an STPIR algorithm specifically includes:

[0017] Based on the three-frequency carrier phase observations, the expression of the three-frequency geometry-free phase combination observations is constructed. Among them, L abc (k) is the three-frequency geometry-free phase combination observation value with combination coefficients (a, b, c) at epoch k; λ m , m=1,2,3 are the wavelengths of the carrier phases of the three frequencies; m = 1, 2, 3 are the observed values ​​of the carrier phase of the three frequencies; N abc is the ambiguity of the three-frequency geometric phase-free combination observation; β abc is the ionospheric delay amplification factor of the three-frequency geometry-free phase combination; is the ionospheric delay of the L1 frequency carrier phase observation; ε abc It is the noise of the three-frequency observation value without geometric phase combination;

[0018] Divide both sides of the constructed three-frequency geometry-free phase combination observation value expression by the wavelength λ1 of the carrier phase of the L1 frequency to obtain the PIR phase combination observation value expression in, is the PIR phase combination observation value at epoch k; N m , m = 1, 2, 3 are the ambiguities of the carrier phase observations of the three frequencies; I res is the ionospheric residual of the PIR phase combination observation;

[0019] The combined observation value of PIR phase at epoch k The STPIR cycle slip decision expression is obtained by performing two time differences using the STPIR algorithm.

[0020] Among them, D STPIR (k) is the STPIR cycle slip decision quantity at epoch k; I res (k) is the ionospheric residual of the PIR phase combination observation at epoch k;

[0021] Two STPIR cycle slip decision variables are constructed using different combination coefficients.

[0022] Optionally, the determining of the satellite-to-earth pseudorange based on the inertial data and the triple-frequency carrier phase observation value by Kalman filter time update and in combination with precise ephemeris specifically includes:

[0023] After the inertial data and the three-frequency carrier phase observation values ​​are input into the positioning model as the measurement values, the Kalman filter time update formula x k|k-1 =F k|k-1 x k-1 Predict the spatial position of the mobile station at epoch k Among them, x k|k-1 is the predicted state vector; x k-1 is the state vector of k-1 epoch; F k|k-1 is the state transfer matrix;

[0024] The spatial position of satellite s at epoch k is obtained by interpolating precise ephemeris using Lagrange interpolation method

[0025]

[0026] Based on the spatial position of satellite s at epoch k and the spatial position of the mobile station at epoch k Using formula Get the satellite-earth pseudorange at epoch k

[0027] Optionally, constructing an ultra-wide lane phase combination observation value according to the satellite-to-earth pseudorange to obtain an ultra-wide lane phase combination cycle slip decision amount specifically includes:

[0028] Linearly expand the expression of the ultra-wide lane phase combination observation value at k epochs, and replace the real pseudorange in the expression of the ultra-wide lane phase combination observation value at k epochs with the satellite-earth pseudorange

[0029] The satellite with the highest elevation angle is determined as the reference satellite, and the ultra-wide lane phase combination observation values ​​of other satellites are subtracted from the ultra-wide lane phase combination observation values ​​of the reference satellite to obtain differential observation values;

[0030] The differential observations are subtracted between epochs to obtain the expression of the cycle slip decision quantity of the ultra-wide lane phase combination at epoch k: Among them, D INS-EWL is the cycle slip decision quantity of the ultra-wide lane phase combination at epoch k; is the double difference operator symbol; N ijl is the ambiguity of the ultra-wide lane phase combination observation; ε ijl is the ultra-wide lane phase combination observation noise; ε INS is the mean error predicted by the inertial navigation system; ijl is the wavelength of the ultra-wide lane phase combination observation value.

[0031] Optionally, constructing a cycle slip separation equation based on the STPIR cycle slip decision quantifier and the ultra-wide lane phase combination cycle slip decision quantifier specifically includes:

[0032] Cycle slip separation equation is constructed based on STPIR cycle slip decision quantifier and ultra-wide lane phase combination cycle slip decision quantifier Wherein, ΔN1, ΔN2 and ΔN3 are the cycle slip estimation values ​​in the carrier phase observation values ​​of L1 frequency, L2 frequency and L3 frequency respectively; D STPIR-1 and D STPIR-1 The STPIR cycle slip decision volume constructed for the combination coefficients (a1, b1, c1) and (a2, b2, c2) respectively; D INS-EWL The ultra-wide lane phase combination cycle slip decision quantity is constructed based on the ultra-wide lane phase combination coefficient (i, j, l).

[0033] Optionally, after solving the cycle slip separation equation to obtain the cycle slip estimation value and repairing it, the method further includes:

[0034] The cycle slip estimation is rounded to an integer value, and the integer value is substituted into the cycle slip repair success rate expression: Among them, P0 is the repair success rate; erfc represents the complementary error function, round(ΔN) represents the rounding operation of the cycle slip estimate ΔN; n is the number to be summed; σ is the standard deviation of the cycle slip estimate ΔN.

[0035] In a second aspect, the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the single-station triple-frequency cycle slip detection and repair method.

[0036] In a third aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the single-station triple-frequency cycle slip detection and repair method.

[0037] In a fourth aspect, the present application provides a computer device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the single-station triple-frequency cycle slip detection and repair method.

[0038] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0039] The present application provides a single-station three-frequency cycle slip detection and repair method, product, medium and equipment, and specifically relates to a single-station three-frequency cycle slip detection and repair method that combines a second-order time-difference phaseionosphere residual (STPIR) method and an INS-assisted ultra-wide lane phase combination. First, the STPIR algorithm is used to construct an STPIR cycle slip decision value for the obtained three-frequency carrier phase observation value, and then the satellite-earth pseudorange is determined based on inertial data and the three-frequency carrier phase observation value using precise ephemeris to replace the real pseudorange in the linear expansion of the ultra-wide lane phase combination observation value, thereby obtaining the ultra-wide lane phase combination cycle slip decision value, and finally the linearly independent ultra-wide lane phase combination cycle slip decision value and the STPIR cycle slip decision value are combined to detect in real time whether there is a cycle slip in the carrier phase combination observation value and repair it. Therefore, the single-station three-frequency cycle slip detection and repair method, product, medium and equipment provided by the present application can effectively improve the accuracy and efficiency of single-station three-frequency cycle slip detection and repair. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 A flow chart of the single-station triple-frequency cycle slip detection and repair method provided for this application;

[0042] Figure 2 Schematic diagram of the single-station triple-frequency cycle slip detection and repair method provided in this application. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0044] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0045] like Figure 1 and Figure 2 As shown, the present application discloses a single-station triple-frequency cycle slip detection and repair method, comprising:

[0046] Step 1: Obtain inertial data and triple-frequency carrier phase observations.

[0047] Specifically, an INS with MEMS level or higher accuracy is used to work simultaneously with a single-station GNSS receiver. The angular velocity and acceleration data are collected as inertial data through the two sensors, the gyroscope and the accelerometer in the INS. The three-frequency carrier phase observations are collected through the single-station GNSS receiver. The three-frequency carrier phase observations described in this application include L1 frequency carrier phase observations, L2 frequency carrier phase observations, and L3 frequency carrier phase observations. This application also needs to obtain precise ephemeris through precise orbit products. The inertial data, three-frequency carrier phase observations, and precise ephemeris obtained in this application are used for cycle slip detection of carrier phase combination observations in subsequent steps.

[0048] In addition, when selecting INS, the accuracy of the gyroscope and accelerometer must be fully guaranteed, the sampling frequency of the inertial data must be at least 20 Hz, and the sampling frequency of the three-frequency carrier phase observation must be at least 1 Hz. Ensure that the sampling frequency of the inertial data is higher than the sampling frequency of the three-frequency carrier phase observation, and the satellite cut-off elevation angle is between 10 and 20 degrees.

[0049] Step 2: Based on the three-frequency carrier phase observations, the STPIR algorithm is used to obtain the STPIR cycle slip decision value.

[0050] Firstly, the triple-frequency carrier phase observations obtained by a single-station GNSS receiver are used to construct the triple-frequency geometry-free phase combination observations. Then, the wavelength of the carrier phase of the L1 frequency is divided on both sides of the equation to obtain the PIR phase combination observations. The PIR phase combination observations are time-differentiated twice to obtain the STPIR cycle slip decision quantifier, and two STPIR cycle slip decision quantifiers are constructed using different combination coefficients.

[0051] The step 2 specifically includes:

[0052] Step 2.1: Construct the triple-frequency geometry-free phase combination observation expression based on the triple-frequency carrier phase observation:

[0053]

[0054] Among them, L abc (k) is the three-frequency geometry-free phase combination observation value with combination coefficients (a, b, c) at epoch k; λ m , m=1,2,3 are the wavelengths of the carrier phases of the three frequencies; m = 1, 2, 3 are the observed values ​​of the carrier phase of the three frequencies; N abc is the ambiguity of the three-frequency geometric phase-free combination observation, N abc=aλ1N1+bλ2N2+cλ3N3, N m , m = 1, 2, 3 are the ambiguities of the carrier phase observations of the three frequencies; β abc is the ionospheric delay amplification factor of the three-frequency geometry-free phase combination, is the ionospheric delay of the observed value of the carrier phase at L1 frequency; abc is the three-frequency carrier phase combination observation noise, ε abc =aλ1ξ1+bλ2ξ2+cλ3ξ3,ξ m ,m=1,2,3 is the noise of the carrier phase observation values ​​of the three frequencies.

[0055] Step 2.2: Divide both sides of the constructed three-frequency geometry-free phase combination observation value expression by the wavelength λ1 of the carrier phase of the L1 frequency to obtain the PIR phase combination observation value expression:

[0056]

[0057] in, is the PIR phase combination observation value at epoch k; I res is the ionospheric residual of the PIR phase combination observation, I res =β abc I1 / λ1 2 , I1 is the ionospheric residual of the carrier phase at L1 frequency.

[0058] Step 2.3: Combine the PIR phase observations at epoch k The sequence is time-differentiated using the STPIR algorithm to obtain the PIR phase combination observation value. The PIR cycle slip decision quantity is then time-differentiated to obtain the STPIR cycle slip decision quantity expression:

[0059]

[0060] Among them, D STPIR (k) is the STPIR cycle slip decision quantity at epoch k; I res (k) is the ionospheric residual of the PIR phase combination observation at epoch k.

[0061] Step 2.4: Construct two STPIR cycle slip decision variables using different combination coefficients.

[0062] Specifically, when selecting the combination coefficient, two factors are mainly considered: first, the ionospheric delay amplification factor β abc Approaching 0, and secondly, making the three-frequency carrier phase combination observation noise ε abc Small enough to be ignored.

[0063] In addition, after constructing two STPIR cycle slip decision quantities, the present application also analyzes the mean error of the STPIR cycle slip decision quantity by setting the corresponding STPIR cycle slip detection threshold. When the STPIR cycle slip decision quantity is greater than the STPIR cycle slip detection threshold, it is considered that the carrier phase combination observation value corresponding to the decision quantity has a cycle slip.

[0064] Specifically, after two sets of optimal combination coefficients are used to construct two STPIR cycle slip decision quantities, the error in STPIR cycle slip detection is analyzed according to the error propagation law, and the calculation formula is:

[0065]

[0066] in, Represents the mean error of the carrier phase observation value at each frequency.

[0067] If the STPIR cycle slip detection threshold is too large, small cycle slips may be missed; if it is too small, small cycle slips may be misdetected. Therefore, this application sets the STPIR cycle slip detection threshold to 3σ. STPIR , the confidence level is 99.7% when D STPIR (k)>3σ STPIR , then it is considered that the carrier phase combination observation value corresponding to the decision quantity has a cycle slip.

[0068] Step 3: Based on the inertial data and the triple-frequency carrier phase observations, the satellite-earth pseudorange is determined by Kalman filter time update and precise ephemeris.

[0069] Firstly, the inertial data and the three-frequency carrier phase observation values ​​are input into the PPP / INS tightly combined positioning model as the measurement values. The spatial position of the mobile station at epoch k is obtained by Kalman filter time update. Then, the precise ephemeris is interpolated by Lagrange interpolation method to obtain the spatial position of the satellite at any time, including the spatial position of the satellite at epoch k. Finally, the satellite-to-earth pseudorange ρ assisted by INS at epoch k is calculated by combining the spatial position of the mobile station at epoch k predicted by INS and the spatial position of the satellite at epoch k. INS .

[0070] The step 3 specifically includes:

[0071] Step 3.1: After the inertial data and the three-frequency carrier phase observation values ​​are input into the PPP / INS tightly integrated positioning model as the measurement values, the spatial position of the mobile station at epoch k is predicted by the Kalman filter time update formula shown in formula (5):

[0072] x k|k-1 =F k|k-1 x k-1 (5)

[0073] Among them, xk|k-1 is the predicted state vector; x k-1 is the state vector of k-1 epoch; F k|k-1 is the state transfer matrix. The spatial position of the mobile station at epoch k is obtained by the components of the predicted state vector in the x, y, and z directions.

[0074] The state vector x of the PPP / INS tight combination positioning model at epoch k is k for:

[0075]

[0076] Where φ represents the attitude angle vector; v represents the velocity vector; p represents the position vector; b g is the gyro bias; b a is the accelerometer zero bias; t r,12 It indicates the receiver clock error of the L1 frequency and L2 frequency ionosphere-free combination after the original receiver clock error absorbs the pseudo-range code delay; zwd r represents the receiver quasi-zenith tropospheric delay; is the ionospheric delay of all satellite L1 frequencies in the current epoch; is the ambiguity of the three frequencies of all satellites in the current epoch.

[0077] The observation vector Z of the PPP / INS tight combination positioning model at epoch k k for:

[0078] Z k =[L INS -LP INS -P] T (7)

[0079] Where L and P represent GNSS pseudorange and carrier phase observations respectively; L INS and P INS are the pseudorange and carrier phase observations predicted by INS respectively.

[0080] Step 3.2: GNSS precise ephemeris can provide satellite orbit data with a certain time resolution. The spatial position of the satellite at any time can be obtained by interpolating the precise ephemeris using the Lagrange interpolation method, including the spatial position of satellite s at epoch k.

[0081] Step 3.3: Based on the spatial position of satellite s at epoch k Combined with the INS mechanical arrangement method, the spatial position of the mobile station at epoch k predicted by INS is obtained Get the satellite-earth pseudorange at epoch k

[0082]

[0083] Step 4: Construct the ultra-wide lane phase combination observation value according to the satellite-to-earth pseudorange and obtain the ultra-wide lane phase combination cycle slip decision value.

[0084] First, the ultra-wide lane carrier phase combination observations at epoch k are linearly expanded using the satellite-to-earth pseudorange assisted by INS. Substituting the true pseudorange in the linear expression The INS-assisted ultra-wide lane phase combination observation value is constructed, and then the satellite with the highest elevation angle is selected as the reference satellite. The k-epoch INS-assisted ultra-wide lane phase combination cycle slip decision value is obtained by making differences with the reference satellite combined observation value and between epochs.

[0085] The step 4 specifically includes:

[0086] Step 4.1: The expression of the ultra-wide lane phase combination observation value at k epochs of linear expansion is:

[0087]

[0088] Wherein, (i, j, l) is the ultra-wide lane phase combination coefficient, and satisfies i+j+l=0; is the carrier phase observation value in weeks; m' represents the wet projection function; zwd r represents the wet delay of the zenith of a single-station GNSS receiver to the process; c v is the speed of light; t r,12 represents the receiver clock error of L1 frequency and L2 frequency observations after deionospheric combination; η ijk is the ionospheric delay amplification factor of the ultra-wide lane phase combination, λ ijl and ε ijl are the wavelength and noise of the phase combination observation value, respectively,

[0089] Satellite-to-Earth Pseudorange with INS Substituting the true pseudorange in the linear expression The expression for constructing the INS-assisted ultra-wide lane phase combination observation value is:

[0090]

[0091] Among them, ε INS is the mean error predicted by the inertial navigation system.

[0092] Step 4.2: Select the satellite with the highest elevation angle as the reference satellite, and first combine the ultra-wide lane phase observations of other satellites Ultra-wide lane phase combination observations with reference satellites Make a difference and get the difference observation value

[0093] Step 4.3: Difference observations By making a difference between epochs, we can get the expression of the cycle slip decision quantity of the ultra-wide lane phase combination at epoch k:

[0094]

[0095] Among them, D INS-EWL is the cycle slip decision quantity of the ultra-wide lane phase combination at epoch k; is the double difference operator symbol; N ijl is the ambiguity of the ultra-wide lane phase combination observation; ε ijl is the ultra-wide lane phase combination observation noise; ijl is the wavelength of the ultra-wide lane phase combination observation value.

[0096] When selecting the INS-assisted ultra-wide lane phase combination coefficient, two factors must also be considered: one is to make the ionospheric delay amplification factor approach 0, and the other is to make the combined observation noise small enough to be negligible.

[0097] In addition, after constructing the ultra-wide lane phase combination cycle slip decision quantity, the present application also analyzes the mean error of the ultra-wide lane phase combination cycle slip decision quantity, and sets the corresponding ultra-wide lane phase cycle slip detection threshold. When the ultra-wide lane phase combination cycle slip decision quantity is greater than the ultra-wide lane phase cycle slip detection threshold, it is considered that the carrier phase combination observation value corresponding to the decision quantity has a cycle slip.

[0098] Specifically, the INS-assisted ultra-wide lane phase combination cycle slip decision quantity is constructed by using the optimal ultra-wide lane phase combination coefficient. According to the error propagation law, the mean error σ of the ultra-wide lane phase combination cycle slip decision quantity is analyzed. INS-EWL , and its calculation formula is:

[0099]

[0100] Among them, σ EWL is the root mean square error of the ultra-wide lane phase combination observations, f m , m = 1, 2, 3 represents the frequency of the carrier phase observation value; σ INS is the independent navigation error of INS over time t, g represents the acceleration due to gravity.

[0101] Set the INS-assisted ultra-wide lane phase cycle slip detection threshold to 3σ INS-EWL , when D INS-EWL >3σ INS-EWL , then it is considered that the carrier phase combination observation value corresponding to the decision quantity has a cycle slip.

[0102] Step 5: Construct a cycle slip separation equation based on the STPIR cycle slip decision quantifier and the ultra-wide lane phase combination cycle slip decision quantifier.

[0103] Three equations are constructed in turn according to the combined relationship between three cycle slip decision quantities (two STPIR cycle slip decision quantities and one ultra-wide lane phase combination cycle slip decision quantity) and the three-frequency carrier phase observation values. The simultaneous equations can be used to obtain the estimated values ​​of the cycle slips in the phase observation values ​​of the three frequencies.

[0104] The three equations are combined to obtain the cycle slip separation equation:

[0105]

[0106] Where ΔN1, ΔN2 and ΔN3 are the cycle slip estimates in the phase observations of each frequency; D STPIR-1 and D STPIR-1 The STPIR cycle slip decision volume constructed for the combination coefficients (a1, b1, c1) and (a2, b2, c2) respectively; D INS-EWL The ultra-wide lane phase combination cycle slip decision quantity constructed by the combination coefficient (i, j, l).

[0107] Step 6: Solve the cycle slip separation equation to obtain the cycle slip estimate and perform repair.

[0108] The cycle slip estimation is rounded off to get an integer value, and the integer value is substituted into the cycle slip repair success rate expression:

[0109]

[0110] Among them, P0 is the repair success rate; erfc represents the complementary error function, round(ΔN) represents the rounding operation of the cycle slip estimate ΔN; n is the number to be summed; σ is the standard deviation of the cycle slip estimate ΔN.

[0111] If the confidence level ζ is given, when P0>ζ, the cycle slip repair is considered successful. Substituting the estimated values ​​of the three frequency cycle slips into the cycle slip success rate calculation formula in turn, the repair status of all cycle slips in the current epoch can be obtained.

[0112] In summary. The single-station three-frequency cycle slip detection and repair method of the present application adopts the STPIR algorithm to construct two STPIR cycle slip decision quantities for the three-frequency carrier phase observations obtained by the single-station GNSS receiver; the satellite-to-earth pseudorange is obtained by using the mobile station position predicted by INS and the satellite position calculated by the precise ephemeris, which replaces the real pseudorange in the ultra-wide lane phase combination observation to construct the third cycle slip decision quantity; the three linearly independent cycle slip decision quantities can be combined to detect in real time whether there is a cycle slip in the carrier phase combination observation; according to the combined relationship between each cycle slip decision quantity of the current epoch and the cycle slip of the three frequency observations, three unrelated equations can be established, and the estimated value of the cycle slip in the three-frequency carrier phase can be obtained by combining the equations; the integer closest to the estimated value is obtained by rounding, and substituted into the cycle slip repair success rate expression. If the success rate is greater than the given confidence level, the cycle slip repair is considered to be successful.

[0113] Compared with the prior art, the single-station triple-frequency cycle slip detection and repair method of the present application has the following beneficial effects:

[0114] (1) The single-station three-frequency cycle slip detection and repair method of the present application not only detects the three-frequency cycle slip but also repairs it, and uses a cycle slip repair success rate calculation formula to evaluate the reliability of the cycle slip repair. This method reduces the single-station PPP filter initialization frequency to a certain extent.

[0115] (2) Based on the traditional PIR algorithm, the single-station three-frequency cycle slip detection and repair method of this application takes into account the impact of the active ionosphere on cycle slip detection and introduces the STPIR algorithm, which can effectively weaken the interference of the ionospheric delay trend quantity on the cycle slip decision quantity.

[0116] (3) The single-station three-frequency cycle slip detection and repair method proposed in this application constructs an INS-assisted ultra-wide lane phase combination cycle slip decision quantity suitable for single-station PPP, providing a new idea for PPP data preprocessing.

[0117] In some embodiments, the present application also provides a computer program product, including a computer program, which implements the single-station triple-frequency cycle slip detection and repair method when executed by a processor.

[0118] In some embodiments, the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the single-station triple-frequency cycle slip detection and repair method.

[0119] In some embodiments, the present application also provides a computer device, including a processor, a memory, an input / output interface (Input / Output, referred to as I / O), a communication interface, and a computer program stored in the memory and executable on the processor, and the processor executes the computer program to implement the single-station three-frequency cycle slip detection and repair method.

[0120] The processor, memory and input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store pending transactions. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, the single-station three-frequency cycle slip detection and repair method is implemented.

[0121] It should be noted that the object information (including but not limited to object device information, object personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the object or fully authorized by all parties, and the collection, use and processing of relevant data need to comply with relevant laws, regulations and standards of relevant countries and regions.

[0122] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ReadOnlyMemory, ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0123] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0124] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A single-station triple-frequency cycle slip detection and repair method, characterized in that: include: Acquire inertial data and triple-frequency carrier phase observation values; the triple-frequency carrier phase observation values ​​include L1 frequency carrier phase observation values, L2 frequency carrier phase observation values, and L3 frequency carrier phase observation values; Based on the three-frequency carrier phase observations, the STPIR algorithm is used to obtain the STPIR cycle slip decision value; Based on inertial data and triple-frequency carrier phase observations, the satellite-to-earth pseudorange is determined by Kalman filter time update and precise ephemeris. The ultra-wide lane phase combination observation value is constructed according to the satellite-to-earth pseudorange to obtain the ultra-wide lane phase combination cycle slip decision value; The cycle slip separation equation is constructed based on the STPIR cycle slip decision quantifier and the ultra-wide lane phase combination cycle slip decision quantifier. Solve the cycle slip separation equation to obtain the cycle slip estimate and perform repair.

2. The single-station triple-frequency cycle slip detection and repair method according to claim 1, characterized in that: The obtaining of inertial data and triple-frequency carrier phase observation values ​​specifically includes: The inertial navigation system and the single-station GNSS receiver are made to work simultaneously, and the angular velocity and acceleration data are collected as inertial data through the gyroscope and accelerometer in the inertial navigation system, and the triple-frequency carrier phase observation values ​​are collected through the single-station GNSS receiver.

3. The single-station triple-frequency cycle slip detection and repair method according to claim 1, characterized in that: The STPIR cycle slip decision amount is obtained by using the STPIR algorithm based on the three-frequency carrier phase observation value, specifically including: Based on the three-frequency carrier phase observations, the expression of the three-frequency geometry-free phase combination observations is constructed. Among them, L abc (k) is the three-frequency geometry-free phase combination observation value with combination coefficients (a, b, c) at epoch k; λ m , m=1,2,3 are the wavelengths of the carrier phases of the three frequencies; is the observed value of the carrier phase of the three frequencies; N abc is the ambiguity of the three-frequency geometric phase-free combination observation; β abc is the ionospheric delay amplification factor of the three-frequency geometry-free phase combination; is the ionospheric delay of the L1 frequency carrier phase observation; ε abc It is the noise of the three-frequency observation value without geometric phase combination; Divide both sides of the constructed three-frequency geometry-free phase combination observation value expression by the wavelength λ1 of the carrier phase of the L1 frequency to obtain the PIR phase combination observation value expression in, is the PIR phase combination observation value at epoch k; N m , m = 1, 2, 3 are the ambiguities of the carrier phase observations of the three frequencies; I res is the ionospheric residual of the PIR phase combination observation; The combined observation value of PIR phase at epoch k The STPIR algorithm is used to perform two time differences to obtain the STPIR cycle slip decision expression. Among them, D STPIR (k) is the STPIR cycle slip decision quantity at epoch k; I res (k) is the ionospheric residual of the PIR phase combination observation at epoch k; Two STPIR cycle slip decision variables are constructed using different combination coefficients.

4. The single-station triple-frequency cycle slip detection and repair method according to claim 1, characterized in that: The method of determining the satellite-to-earth pseudorange based on the inertial data and the three-frequency carrier phase observation value by updating the Kalman filter time and combining the precise ephemeris specifically includes: After the inertial data and the three-frequency carrier phase observation values ​​are input into the positioning model as the measurement values, the Kalman filter time update formula x k|k-1 =F k|k-1 x k-1 Predict the spatial position of the mobile station at epoch k Among them, x k|k-1 is the predicted state vector; x k-1 is the state vector of k-1 epoch; F k|k-1 is the state transfer matrix; The spatial position of satellite s at epoch k is obtained by interpolating precise ephemeris using Lagrange interpolation method Based on the spatial position of satellite s at epoch k and the spatial position of the mobile station at epoch k Using formula Get the satellite-earth pseudorange at epoch k 5. The single-station triple-frequency cycle slip detection and repair method according to claim 1, characterized in that: The step of constructing an ultra-wide lane phase combination observation value according to the satellite-to-earth pseudorange to obtain an ultra-wide lane phase combination cycle slip decision amount specifically includes: Linearly expand the expression of the ultra-wide lane phase combination observation value at k epochs, and replace the real pseudorange in the expression of the ultra-wide lane phase combination observation value at k epochs with the satellite-earth pseudorange The satellite with the highest elevation angle is determined as the reference satellite, and the ultra-wide lane phase combination observation values ​​of other satellites are subtracted from the ultra-wide lane phase combination observation values ​​of the reference satellite to obtain differential observation values; The differential observations are subtracted between epochs to obtain the expression of the cycle slip decision quantity of the ultra-wide lane phase combination at epoch k: Among them, D INS-EWL is the cycle slip decision quantity of the ultra-wide lane phase combination at epoch k; is the double difference operator symbol; N ijl is the ambiguity of the ultra-wide lane phase combination observation; ε ijl is the ultra-wide lane phase combination observation noise; ε INS is the mean error predicted by the inertial navigation system; ijl is the wavelength of the ultra-wide lane phase combination observation value.

6. The single-station triple-frequency cycle slip detection and repair method according to claim 1, characterized in that: The cycle slip separation equation is constructed based on the STPIR cycle slip decision quantity and the ultra-wide lane phase combination cycle slip decision quantity, specifically including: Cycle slip separation equation is constructed based on STPIR cycle slip decision quantifier and ultra-wide lane phase combination cycle slip decision quantifier Wherein, ΔN1, ΔN2 and ΔN3 are the cycle slip estimation values ​​in the carrier phase observation values ​​of L1 frequency, L2 frequency and L3 frequency respectively; D STPIR-1 and D STPIR-1 The STPIR cycle slip decision volume constructed for the combination coefficients (a1, b1, c1) and (a2, b2, c2) respectively; D INS-EWL The ultra-wide lane phase combination cycle slip decision quantity is constructed based on the ultra-wide lane phase combination coefficient (i, j, l).

7. The single-station triple-frequency cycle slip detection and repair method according to claim 1, characterized in that: After solving the cycle slip separation equation to obtain the cycle slip estimation value and repairing it, the method further includes: The cycle slip estimation is rounded to an integer value, and the integer value is substituted into the cycle slip repair success rate expression: Among them, P0 is the repair success rate; erfc represents the complementary error function, round(ΔN) represents the rounding operation of the cycle slip estimate ΔN; n is the number to be summed; σ is the standard deviation of the cycle slip estimate ΔN.

8. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the single-station triple-frequency cycle slip detection and repair method described in any one of claims 1 to 7 is implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the single-station triple-frequency cycle slip detection and repair method described in any one of claims 1 to 7 is implemented.

10. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the single-station triple-frequency cycle slip detection and repair method according to any one of claims 1 to 7.

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