CN-121995413-A - Single Beidou multi-frequency positioning error correction method, device and medium

CN121995413ACN 121995413 ACN121995413 ACN 121995413ACN-121995413-A

Abstract

The invention relates to the technical field of satellite navigation positioning, and discloses a single Beidou multi-frequency positioning error correction method, device and medium, which comprise the steps of establishing a single Beidou multi-frequency positioning observation model, wherein the single Beidou multi-frequency positioning observation model comprises a pseudo-range observation equation and a carrier wave observation equation; the method comprises the steps of carrying out double-difference processing on observed values, eliminating common errors such as satellite clock difference and receiver clock difference, respectively carrying out accurate correction on troposphere delay and ionosphere delay, wherein the ionosphere delay correction adopts improved Kalman filtering estimation parameters, carrying out self-adaptive carrier phase smoothing processing on double-difference pseudo-range observed values, adopting a multi-dimensional self-adaptive threshold cycle slip detection and restoration algorithm based on dynamic programming, carrying out multi-frequency ambiguity fixation by using an LAMBDA method, and carrying out anti-difference self-adaptive filtering by adopting an IGG weight function. Compared with the prior art, the invention has the advantages of obviously improving the positioning precision, enhancing the environmental adaptability, improving the system reliability, supporting the multi-frequency treatment and the like.

Inventors

GUO TAO
YE RUI
TAO LIMING
CHEN GONG
LI JIN
DENG KAIFENG

Assignees

贵州电网有限责任公司

Dates

Publication Date: 20260508
Application Date: 20251218

Claims (10)

1. A single Beidou multi-frequency positioning error correction method is characterized by comprising the steps of, Establishing a single Beidou multi-frequency positioning observation model which comprises a pseudo-range observation equation and a carrier wave observation equation; Performing double-difference processing on the observed value to eliminate satellite clock difference and receiver clock difference common errors; Correcting troposphere delay in the double-difference observed value by adopting a method of combining zenith delay correction and mapping function; Estimating ionospheric delay parameters by adopting Kalman filtering of a first-order Markov model, and correcting ionospheric delay in a double-difference observed value; Performing self-adaptive carrier phase smoothing on the double-difference pseudo-range observation value; Performing cycle slip detection and repair on the carrier phase observation value by adopting a multi-dimensional self-adaptive threshold cycle slip detection and repair algorithm based on dynamic programming; Performing multi-frequency ambiguity fixation on the processed carrier phase observation value, and obtaining a positioning result by adopting an LAMBDA method; and performing robust adaptive filtering on the observed values, and removing abnormal observed values by adopting an IGG weight function.
2. The method for correcting single Beidou multi-frequency positioning error of claim 1, wherein establishing a single Beidou multi-frequency positioning observation model comprises establishing a pseudo-range observation equation, Establishing a carrier observation equation: Wherein, the For a pseudorange observation of satellite s at frequency i by receiver u, As an observation of the phase of the carrier, In order to be a geometric distance, In order to achieve the light velocity, the light beam is, In order for the receiver to be clocked out, For the satellite clock-difference, In order for the tropospheric air to be retarded, In order for the ionosphere atmosphere to be delayed, For the code hardware delay at the receiver side on frequency i, For the code hardware delay at frequency i at the satellite side, As the carrier wavelength is used, As a carrier phase ambiguity parameter, For the pseudo-range observation noise, Noise is observed for the carrier phase.
3. The method for correcting single Beidou multi-frequency positioning error of claim 2, wherein double difference processing comprises establishing a double difference pseudo-range observation equation, Establishing a double-difference carrier observation equation: Wherein, the Is a double-difference pseudo-range observation, Is a double difference carrier phase observation value, Representing a double difference operator, firstly carrying out inter-station difference and then inter-planet difference, Is a geometric distance of double difference, For a dual difference tropospheric delay, For a dual differential ionospheric delay, r, b denote a reference station and a rover, a, n denote a reference satellite and a non-reference satellite, As the carrier wavelength is used, Is a dual difference carrier phase ambiguity parameter, For the double-difference pseudorange observation noise, Noise is observed for the dual differential carrier phase.
4. The method for correcting single Beidou multi-frequency positioning error of claim 3, wherein tropospheric delay in the double difference observation is corrected by a calculation formula of, Wherein, the In order for the tropospheric delay to be sufficient, For zenithal tropospheric dry delay, For zenithal tropospheric wet retardation, As a function of the dry delay mapping, Is a wet delay mapping function.
5. The method for correcting single Beidou multi-frequency positioning error of claim 4, wherein correcting ionospheric delay in double difference observations comprises adopting Kalman filtering of a first order Markov model, Establishing a state transition equation: establishing an observation equation: Wherein, the The ionospheric delay state vector for the kth epoch, The ionospheric delay state vector for the k-1 epoch, In the form of a state transition matrix, In order for the process to be noisy, In order to observe the vector of the light, In order to observe the matrix, Is observation noise; The state transition matrix adopts a first order Markov model: Wherein, the As the inverse of the time constant of interest, Is the sampling interval.
6. The method for correcting single Beidou multi-frequency positioning error of claim 5, wherein the adaptive carrier phase smoothing is performed according to a calculation formula, Wherein, the For a smoothed pseudorange for the kth epoch, For a smoothed pseudorange of the k-1 epoch, For the raw pseudorange observations, As an observation of the phase of the carrier, Is the carrier phase observation for the k-1 epoch, Is an adaptive smoothing factor.
7. The method for correcting single Beidou multi-frequency positioning error of claim 6 wherein the adaptive smoothing factor comprises, Where k is the current epoch number, And determining the ratio of the standard deviation of the pseudo-range observation noise to the standard deviation of the carrier phase observation noise for the base smoothing window length.
8. The method for correcting single Beidou multi-frequency positioning error of claim 7, wherein performing cycle slip detection and repair on the carrier phase observation value comprises establishing a state transition model based on a dynamically planned multidimensional adaptive threshold cycle slip detection and repair algorithm, Defining a cost function: the Viterbi algorithm is adopted to solve a threshold sequence for minimizing the cost function: Wherein, the Is the state vector for the kth epoch, For the carrier-to-noise ratio, For the rate of change of the doppler shift, As the standard deviation of the carrier phase, The transpose of the matrix is represented, As a function of the cost, 、、 As the weight coefficient of the light-emitting diode, In order to be able to detect the probability of missing, For the probability of a false alarm, In order to calculate the cost of the calculation, In order to minimize the threshold sequence of cost functions, Is an epoch index.
9. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that the processor, when executing the computer program, implements the steps of a single-beidou multi-frequency positioning error correction method according to any one of claims 1 to 7.
10. A computer readable storage medium having stored thereon a computer program, characterized in that the computer program when executed by a processor implements the steps of a single beidou multi-frequency positioning error correction method according to any one of claims 1 to 7.

Description

Single Beidou multi-frequency positioning error correction method, device and medium Technical Field The invention relates to the technical field of satellite navigation positioning, in particular to a single Beidou multi-frequency positioning error correction method, device and medium. Background The Beidou satellite navigation system (BDS) is taken as a global satellite navigation system which is independently researched and developed in China, and plays an important role in high-precision positioning application. Along with the continuous perfection of the Beidou system and the expansion of the application field, the requirements on the positioning precision are higher and higher. However, in practical applications, there are various error sources in beidou multi-frequency positioning, and these errors seriously affect positioning accuracy and reliability. The existing Beidou multi-frequency positioning technology mainly adopts a traditional error correction method, and comprises troposphere delay correction, ionosphere delay correction, carrier phase smoothing pseudo-range technology, ambiguity fixation and the like. However, these conventional methods have the following technical problems in practical applications: Firstly, modeling accuracy of tropospheric delay and ionospheric delay is not high, and particularly under the condition of a long base line, the traditional modeling method cannot accurately describe the spatial variation characteristic of atmospheric delay, so that the correction effect is not ideal. Secondly, the existing carrier phase smoothing pseudo-range technology lacks self-adaptability, fixed smoothing parameters cannot adapt to different observation environments and signal quality changes, and larger errors are easy to generate in the environments with poor signal quality or high dynamic. And in the traditional cycle slip detection and repair method, the threshold value is set in a lack of self-adaptive mechanism, so that the problem of missed detection or false alarm easily occurs in the fixed threshold value under different environment conditions, and the continuity and reliability of carrier phase observation are affected. Finally, the existing ambiguity fixing method is low in efficiency under the condition of multiple frequencies, and especially when the observation condition is poor, the ambiguity fixing success rate is low, and the improvement of positioning accuracy is affected. Therefore, a more accurate and adaptive single Beidou multi-frequency positioning error correction method is needed to solve the above technical problems and improve the positioning accuracy and reliability. Disclosure of Invention The present invention has been made in view of the above-described problems occurring in the prior art. Therefore, the invention provides a single Beidou multi-frequency positioning error correction method, which can solve the technical problems of low modeling precision of troposphere delay and ionosphere delay, lack of self-adaptability of carrier phase smoothing pseudo-range technology, lack of self-adaptive mechanism of cycle slip detection threshold setting, low multi-frequency ambiguity fixing efficiency and the like in the prior art. The technical scheme includes that a single Beidou multi-frequency positioning error correction method is established and comprises the steps of establishing a single Beidou multi-frequency positioning observation model which comprises a pseudo-range observation equation and a carrier observation equation, conducting double-difference processing on an observation value, eliminating satellite clock difference and receiver clock difference common errors, correcting troposphere delay in the double-difference observation value by adopting a method of combining zenith delay correction and mapping functions, estimating ionosphere delay parameters by adopting Kalman filtering of a first-order Markov model, correcting ionosphere delay in the double-difference observation value, conducting adaptive carrier phase smoothing on the double-difference pseudo-range observation value, conducting cycle slip detection and restoration on the carrier phase observation value by adopting a multi-dimensional adaptive threshold cycle slip detection and restoration algorithm based on dynamic programming, conducting multi-frequency ambiguity fixing on the processed carrier phase observation value, obtaining a positioning result by adopting an LAMBDA method (namely a least square ambiguity reduction related adjustment method), conducting anti-difference adaptive filtering on the observation value, and eliminating an abnormal value by adopting an IGG weight function. As a preferable scheme of the single Beidou multi-frequency positioning error correction method, the method for establishing the single Beidou multi-frequency positioning observation model comprises the steps of establishing a pseudo-range observation equation, Establishing a carrier observation equ