67 results about "Pseudorange" patented technology

The present application provides a method and an apparatus for measuring a relative position of a spacecraft based on GNSS difference. The method includes: acquiring a first long-wave observation combination and a second long-wave observation combination; performing a double-difference ambiguity of whole cycles search according to a pseudo-range double-difference linear equation and a carrier double-difference equation, and determining N first ambiguities of whole cycles to be detected of the first long-wave observation combination and M second ambiguities of whole cycles to be detected of the second long-wave observation combination; determining a first ambiguity of whole cycles and a second ambiguity of whole cycles that satisfy a preset ambiguity of whole cycles condition; and then determining a short-wave double-difference ambiguity of whole cycles to measure the relative position of the spacecraft.

This application discloses an adaptive carrier phase smoothing pseudorange method and apparatus, which smooths the pseudorange of all frequency points in a simple and practical way. As long as there is a continuous carrier without cycle slip at any frequency point, pseudorange smoothing can continue without resetting the filter, so that the pseudorange before and after the positioning frequency point switching is smoothed, improving the smoothing accuracy. Furthermore, using a carrier of any frequency point to smooth the pseudorange of all frequency points reduces the large error caused by the positioning frequency point switching.

Embodiments of the present disclosure disclose a SPP positioning model construction method and device based on factor graph optimization. The specific implementation of the method comprises: constructing a variable node set of a factor graph structure, wherein the to-be-estimated state quantity of each variable node in the variable node set at an epoch includes three-dimensional coordinates of a receiver and four parameters related to clock bias of the receiver; constructing a pseudorange factor set according to the variable node set, wherein the pseudorange factor set includes at least four pseudorange factors; correlating the position parameters between two adjacent epochs in each epoch in an observation window to construct a Doppler velocity factor, obtaining a Doppler velocity factor set, wherein the Doppler velocity factor is a binary factor; constructing a graph optimization cost function according to the pseudorange factor set and the Doppler velocity factor set, and obtaining a SPP positioning model. The implementation can improve the GNSS positioning accuracy in a complex environment.

The application discloses a single-epoch multi-frequency GNSS ambiguity precision factor refinement estimation method. The method comprises the following steps: weighting single-epoch multi-frequency pseudorange and carrier phase observation of a reference station and a rover station respectively; calculating a harmonic mean of the same satellite pseudorange observation weight and a harmonic mean of the carrier phase observation weight; calculating a weighted geometric mean of the multi-frequency carrier wavelength and a weighted geometric mean of the multi-frequency non-difference carrier phase observation standard deviation; constructing a baseline vector non-difference weighted coefficient matrix of the carrier and the pseudorange observation; and finally calculating a single-epoch multi-frequency GNSS ambiguity precision factor value according to the above parameters. The application can realize high-precision estimation when the same or different weighting models are adopted for the pseudorange and the carrier phase, and the estimation precision can reach 10 ‑6 weeks, which is about 99.98% higher than that of a traditional model, and provides a reliable prior success rate estimation for single-epoch multi-frequency GNSS rapid precise positioning.

The application relates to a GMM-assisted vehicle fusion positioning method and system, which comprises the following steps: calculating an IMU pre-integration term according to the angular velocity and acceleration measurement information of an IMU; calculating a dynamics pre-integration term according to the speed measurement information of a wheel speed sensor and the angular velocity measurement information of the IMU in combination with a two-degree-of-freedom vehicle model; constructing an IMU factor and a dynamics factor by using the IMU pre-integration term and the dynamics pre-integration term after obtaining a GNSS measurement signal; constructing a pseudorange factor according to the original observation information of a GNSS receiver in combination with system states; constructing a clock drift factor based on the clock error of the GNSS receiver; constructing a factor graph by combining the constructed factors, wherein the noise of the IMU factor, the dynamics factor and the clock drift factor is Gaussian modeling, and the noise of the pseudorange factor is GMM modeling; and optimizing the factor graph to estimate the positioning information of the vehicle. Compared with the prior art, the application can effectively suppress the influence of abnormal GNSS measurement on positioning, and realizes low-cost and robust high-precision positioning.

The application discloses a single-frequency ionospheric delay autonomous correction method and relates to the field of GNSS positioning. In view of a strong ionospheric disturbance scenario caused by magnetic storm, the method adopts a multi-ionospheric piercing point space-time decoupling algorithm, and only single-frequency pseudorange and carrier phase observation can be used to complete autonomous correction of ionospheric delay error of BDSK. The method does not need to depend on a ground reference station network and a double-frequency receiver hardware condition, and only relies on observation data of the receiver itself to autonomously complete ionospheric delay correction calculation, can be applied to a Beidou single-frequency positioning application scenario in a magnetic storm and the like strong ionospheric disturbance environment, effectively solves a technical problem that in the prior art, in a magnetic storm and the like strong ionospheric disturbance environment, ionospheric delay correction precision of a single-frequency receiver is reduced under a condition that a BDS BAS satellite-based augmentation service is invalid, and significantly improves the precision and operation robustness of Beidou single-frequency positioning in a complex space disturbance environment.

The application discloses a three-dimensional map aided GNSS positioning method based on density clustering improvement, comprising the following steps: constructing a three-dimensional building model, generating a sky mask, pre-generating a sky mask database, judging satellite visibility, scoring the satellite visibility based on a shadow matching algorithm, optimizing candidate point screening rules, introducing an OPTICS clustering algorithm to sort, clean and select candidate points, and screening high-score points; taking the score of the high-score points as a weight, optimizing the calculation formula into a weighted average formula considering cluster weight, and calculating a final position. The positioning method can solve the problem of multiple adjacent peak candidate points in three-dimensional building model aided GNSS pseudorange single point positioning under similar geometric observation conditions in the vicinity of a city area in a complex urban environment, the OPTICS clustering algorithm is adopted to sort data points according to density, small clusters are removed, and effective cleaning and selection of candidate points are realized, so that the positioning precision is effectively improved.

The invention relates to a combined clock synchronization method based on weighting condition adjustment improvement, which realizes high-precision time synchronization in a large-scale sensor node network scene. The method comprises the following steps: carrying out bidirectional ranging on bidirectional communication nodes in a sensor node network by adopting a synchronous bidirectional ranging mechanism to obtain a pseudo-range information model between the nodes; constructing an observation equation according to the pseudo-range information model, and performing estimation solution on the observation equation by adopting a least square method to obtain initial observation estimation; calculating to obtain clock offset error estimation between the nodes according to the pseudo-range information model and the initial observation estimation, and constructing to obtain a weighting condition adjustment model according to the clock offset error estimation; correcting a pseudo-range observation value in the pseudo-range information model according to a weighted condition adjustment model to obtain a de-noised observation value; and constructing a new observation equation according to the de-noised observation value, and performing estimation solution on the new observation equation by adopting a least square method to obtain optimized observation estimation.

The application discloses a GNSS spoofing detection method based on adaptive RAIM and hidden space diffusion model, and relates to the fields of satellite navigation and artificial intelligence.The method comprises the following steps: constructing an adaptive pseudo-range residual feature extractor, wherein the adaptive pseudo-range residual feature extractor is composed of a weight adaptive network and a weighted least squares RAIM; the weight adaptive network is constructed by a graph convolutional neural network, can adaptively correct the pseudo-range observation weight matrix of the weighted least squares RAIM, and can enhance the sensitivity of the pseudo-range residual to the geometric consistency destruction caused by spoofing; the weighted least squares RAIM processes the pseudo-range residual on the basis to extract the multi-scale trend features; constructing a hidden space diffusion model, wherein the hidden space diffusion model is trained by using the multi-scale trend features which are not spoofed, and performs spoofing detection through a state evaluation function.The application can effectively improve the detection performance of the receiver on the GNSS spoofing attack.

The application discloses a terminal positioning method and device, equipment and storage medium, and specifically discloses the following: receiving a ranging code decoding key issued by a core network; receiving encrypted ranging codes broadcast by at least four base stations; using the ranging code decoding key to decrypt the received encrypted ranging codes to obtain original ranging codes corresponding to the base stations; based on the original ranging codes, performing code phase alignment processing on the original ranging codes and copied ranging codes with the same structure as the original ranging codes to obtain the propagation time of signals of the encrypted ranging codes from the base stations to a terminal, and calculating the pseudo distances between the terminal and each base station according to the propagation time; obtaining high-precision geographic positions and clock correction information of the at least four base stations, and based on the pseudo distances corresponding to the at least four base stations respectively, the high-precision geographic positions and the clock correction information, constructing an equation group with the three-dimensional coordinates and clock bias of the terminal as unknowns, and determining the position coordinates of the terminal by solving the equation group.

The technology provides enhanced localization approaches using vehicle-obtained information in place of or to enhance global positioning information to localize a user's position. Such information can be shared with the user's client device in real-time prior to pickup or meeting at a selected location. This can supplement or replace inaccurate localization information available at the client device, and can be done as needed when the user is within a threshold range of one or more autonomous vehicles. A client device of a user can compute its position using the vehicle positioning information. The vehicle positioning approach may be performed when the user is within a certain range of one or more vehicles. Vehicle localization information may also be used to correct the client device's localization information. Here, using hyper-accurate vehicle positioning, one or more vehicles can compute pseudorange errors for each “visible” satellite in a global positioning service.

This invention proposes a reference station network coordinate encryption method based on single-reference-station VRS technology, belonging to the field of satellite navigation and high-precision positioning. The specific process is as follows: The reference station GNSS receiver receives non-differential pseudorange observation data and non-differential carrier phase observation data broadcast by GNSS satellites, forming non-differential observation equations for pseudorange and carrier phase; based on the non-differential pseudorange and carrier phase observation equations, the non-differential error corrections for the pseudorange and carrier phase observations of a single reference station in the reference station network are obtained; based on the principle of spatial correlation of atmospheric errors, during the generation of a single VRS, it is assumed that the atmospheric errors of the actual reference station and the VRS to be generated are consistent. Using the non-differential error corrections of the single reference station, the accurate coordinates of the VRS to be generated, and the satellite position, virtual pseudorange and carrier phase observations are generated to replace the actual reference station, thereby achieving reference station network coordinate encryption; thus protecting the real-time data of the reference station network.

The application discloses a joint correction method and system of GNSS non-tectonic deformation and a storage medium. The method obtains GNSS pseudo-range and carrier phase observation data and precise orbit, clock error and other precise products, constructs three-component displacement time series caused by non-tidal atmospheric load, non-tidal ocean load and land hydrology load and temperature-driven thermal elastic displacement time series, and unifies to a reference frame and a time system consistent with GNSS solution. The non-tectonic displacement vector is interpolated to the observation epoch by time, converted from the local coordinate system ENU to the geocentric rectangular coordinate system, and projected to the line-of-sight direction of the satellite to the reference point of the station to form an equivalent geometric distance correction term; the correction term is applied to the pseudo-range observation and the carrier phase equivalent meter domain observation in the same domain as the observation, and then GNSS daily arc segment precise solution is performed to output the coordinate time sequence, which is preferably used for precise point positioning integer ambiguity fixing technology.

This invention discloses a method for jointly determining the position and time state of a spacecraft by integrating a lunar reference, belonging to the fields of deep space exploration, autonomous navigation, and time synchronization. The method includes: constructing an augmented state vector, which simultaneously includes the spacecraft's position and inertial velocity relative to the Earth's center, its position and inertial velocity relative to the Moon's center, the spacecraft's local clock bias and drift, and the common clock bias and drift of the lunar-based navigation network; acquiring pseudorange and pseudorange rate observation data from the Earth-based and lunar-based base stations, and introducing a precise Earth-Moon ephemeris to construct Earth-Moon position and velocity constraints as virtual observations, combining physical and virtual observations into a unified observation model; constructing a global observation residual vector and configuring a weight matrix; and employing a weighted iterative least squares algorithm to jointly solve the augmented state vector, outputting the synchronization estimation results of the spacecraft's position, velocity, and time state. This invention achieves high-precision autonomous navigation and Earth-Moon time reference synchronization for Earth-Moon spacecraft.

One or more embodiments of the present disclosure provide a Beidou satellite-based positioning method, device, electronic equipment and storage medium. The method comprises: acquiring carrier phase measurement data, pseudo-range measurement data and Doppler observation values of multiple frequency bands of multiple satellites through a mobile receiver and a fixed base station; obtaining double-difference pseudo-range observations and an initial rough coordinate of the mobile receiver according to the pseudo-range measurement data and an inter-station double-difference model; calculating single-frequency ambiguity of a B1 frequency point of the satellite using a three-frequency carrier ambiguity resolution algorithm according to the carrier phase measurement data, and verifying the fixed state of the single-frequency ambiguity of each satellite; constructing a dynamic factor graph according to the single-frequency ambiguity, the carrier phase measurement data, the pseudo-range measurement data and the Doppler observation values; and obtaining a target positioning coordinate of the mobile receiver using a sliding window estimator, with the sum of all residual squares in a preset sliding window being the minimum as an objective function.

The application provides a network RTK differential correction number generation method based on Beidou and low-orbit constellation fusion, which comprises data acquisition, receiving pseudorange observation values and carrier phase observation values of Beidou satellite navigation system satellites and low-orbit constellation satellites through a ground reference station receiver simultaneously; constructing a joint observation model of Beidou satellite navigation system and low-orbit constellation, and using an extended Kalman filtering algorithm to estimate receiver clock difference and system bias between the two systems in real time; adaptive weighted differential correction number calculation, calculating pseudorange differential correction numbers of Beidou satellites and low-orbit satellites respectively based on the estimated system bias; correction number broadcasting, dynamically determining the effective duration of the differential correction number of the low-orbit satellite according to the orbit height of the low-orbit satellite, and encoding the correction numbers of the Beidou satellites and the low-orbit satellites into RTCM text format to broadcast to the user end; the user end receives the correction numbers, corrects the local Beidou satellite and low-orbit satellite observation values, performs joint RTK solving, and verifies and confirms ambiguity fixing.

The application discloses a kind of inter-satellite microwave measurement communication link signal generation and chain building method, comprising: generating transmitting signal based on direct sequence spread spectrum mode, and transmitting signal is divided into mutually orthogonal I branch and Q branch, and the spread spectrum code sequence of different length is modulated to two branches respectively;I branch is used as measurement branch, fixed modulation long code is used and binary offset subcarrier modulation mode is used, and measurement data frame with fixed frame length and information rate is loaded on I branch;Q branch is set to pilot mode or communication mode, short spread spectrum code is modulated in pilot mode and no data is loaded, long spread spectrum code is modulated in communication mode and communication data with configurable information rate is loaded;The start bit of spread spectrum code period of I branch and Q branch is aligned with the start bit of data frame header to the local maintained second pulse, and the generation of inter-satellite microwave measurement communication link transmitting signal is completed.The application can realize acquisition complexity and pseudo-range measurement accuracy under the condition of given bandwidth.

The application provides a GNSS receiver and an energy-saving method, a static state determining method and a storage medium thereof. The method comprises the following steps: selecting four satellites and recording the pseudo distances of the satellites; for each satellite, subtracting the pseudo distance of each epoch from the pseudo distance of the previous epoch to obtain epoch difference data; subtracting the epoch difference data of the other three satellites from the epoch difference data corresponding to the satellite with the highest signal-to-noise ratio to obtain difference difference data; performing time difference between epochs on the three groups of difference difference data to obtain difference time difference data; for each group of difference time difference data, selecting 2N epochs and determining whether the change curvatures of the front and rear N epochs are consistent; if yes, the receiver is in a static state, the acquisition of other satellites is stopped, and positioning calculation is skipped. The technical scheme uses simple data processing to determine the static state of the receiver, avoids subsequent complicated calculation when the receiver is static, and saves energy consumption.

A method and apparatus for generating and distributing signal correction data for use by GNSS receivers. In embodiments, a method for performing signal processing in a radio signal receiver and a moving antenna that moves about a known, fixed location, includes: receiving radio signals from a plurality of transmitters using the moving antenna, where the antenna is moving relative to the received radio signals; performing motion compensated correlation of the signals to generate motion compensated correlation results; determining a measured pseudorange from the receiver and each of the plurality of transmitters; determining a difference between the pseudorange and an expected pseudorange for each transmitter, where the difference represents an atmospheric delay experienced by the signals as the signals propagate from each transmitter to the receiver; and transmitting the delay to a correction data server to be used to generate correction data that is distributed to at least one GNSS receiver.

This invention relates to the field of satellite navigation and positioning and multi-source information fusion technology, specifically a low-cost, high-precision GNSS navigation method for complex urban environments. The method constructs a dual-channel adaptive weighting model based on scene classification results. Pseudorange observations are weighted using a nonlinear smooth reduction based on the Sigmoid function, while carrier phase observations are weighted using a two-way reward / penalty system based on signal-to-noise ratio and environment type. This invention achieves a smooth transition of pseudorange weights through the Sigmoid nonlinear function, avoiding filter divergence caused by hard cutoff. A unique open-field carrier reward mechanism improves positioning accuracy in ideal environments. Furthermore, without increasing hardware costs, only algorithm upgrades can significantly improve the navigation performance of low-cost chips in complex urban environments, demonstrating high engineering application value.

The application discloses a kind of based on double tracking channel RAIM's fraud identification inhibition method, system and equipment, the method includes the signal of each visible satellite double peak capture, obtain the highest peak satellite signal and the secondary high peak satellite signal of captured visible satellite;For highest peak satellite signal allocation main tracking channel, and for secondary high peak satellite signal allocation vice tracking channel;After stable tracking, the pseudorange observation of all visible satellites in vice tracking channel is calculated;Global RAIM is carried out to pseudorange observation, whether global RAIM is passed, if passed, PVT is solved according to pseudorange observation, and real navigation positioning time service result is obtained.The double tracking channel receiver used in the application adopts double peak capture algorithm, and uses two channels to track a satellite.Only if there is still real signal in received signal, correct positioning time service result can be maintained;It is essentially that a set of tracking channel is added to the original structure of traditional receiver, and the difficulty of realization is lower.

This application discloses a GPS receiver information fusion and sharing method, relating to the field of satellite navigation and positioning technology. The method includes: pre-setting a master receiver and a slave receiver to collect raw observation data respectively, forming a joint observation dataset; identifying a common-view satellite set; calculating the pseudorange difference measured by the two receivers, pre-setting a pseudorange threshold, and removing observation data with a pseudorange difference greater than the pseudorange threshold to generate a high-quality observation dataset; calculating the relative clock bias and relative clock bias change rate in the common-view satellite set to obtain a fused observation dataset; constructing a joint observation dataset through time alignment and cross-validation to achieve deep fusion at the raw data level; effectively smoothing single-machine observation noise and solving the heterogeneous clock fusion problem; accurately estimating the relative clock bias and its change rate, dynamically selecting the optimal working mode based on the real-time environmental state to prevent filter divergence, and maintaining usable positioning output through information complementarity or historical data.

This paper proposes a baseline-length-constrained high-precision relative positioning method for BeiDou, comprising the following steps: First, establishing a double-difference relative positioning model using the pseudorange and carrier phase raw observations of the reference station and the rover station; Second, obtaining a strictly baseline-length-constrained objective function based on the double-difference relative positioning model according to the least squares criterion; Third, employing an integer ambiguity search space amplification strategy to achieve effective ambiguity search, and accurately estimating the rover station's position relative to the reference station. This invention utilizes the often underutilized baseline length information of dual antennas in real-world scenarios to improve the relative positioning solution performance, exhibiting higher reliability compared to the traditional unconstrained case. The method employs an integer ambiguity search space amplification strategy, thereby extending the standard LAMBDA algorithm to baseline-length-constrained relative positioning, achieving effective integer ambiguity search.

This application provides a method, system, and device for tropospheric error correction based on BeiDou satellite signals. The method includes: deploying multiple reference stations within a preset coverage area to receive pseudorange and carrier phase observation data from BeiDou satellites, performing gross error elimination and cycle slip detection on the observation data, and constructing an ionospheric-free combined observation equation; combining real-time precise ephemeris and satellite clock bias, calculating the total zenith tropospheric delay of each reference station using precise single-point positioning technology, and obtaining the zenith wet delay using barometric pressure data and an empirical model; further summarizing the wet delay information from multiple reference stations, and establishing a regional wet delay model by combining topographic factors such as altitude, and converting the zenith delay into a tropospheric correction in the satellite line-of-sight direction using a mapping function. This invention can achieve high-precision tropospheric error modeling and correction under high-altitude and complex terrain conditions, and is applicable to power grid inspection, transmission line monitoring, and high-precision positioning services for BeiDou terminals.

This invention provides an adaptive GNSS / INS deep integrated navigation method for multipath environments based on coarse binary classification and pseudorange error prediction. This method deeply integrates GNSS and INS data. In the offline phase, it constructs training samples and pseudorange error supervision labels using raw GNSS / INS observation data and a high-precision reference system, extracting carrier-to-noise ratio, satellite elevation angle, and pseudorange residual features. These features are then used to train a coarse binary classifier to output the probability of suspicious observations, and a pseudorange error regressor to predict pseudorange errors. In the online phase, a feature vector consistent with the offline model is constructed based on receiver observations and the INS recursive state. The regressor output is used to correct the measured pseudorange, and the probability of suspicious observations, the magnitude of the prediction error, and the current residual are fused into a continuous risk quantity. The observation noise covariance matrix is ​​adaptively adjusted and time-smoothed. Finally, the corrected pseudorange observations and the updated covariance matrix are input into a deep integrated Kalman filter to complete the integrated navigation solution and feedback control.

This application discloses a method, apparatus, and computer device for determining location based on deformation monitoring, belonging to the field of positioning processing. The method includes: receiving measurement data from n satellites transmitted by a base station and a monitoring station; determining the geographical location information of the monitoring station relative to the base station based on carrier signals and pseudorange information; obtaining an ambiguity search subset corresponding to the monitoring station relative to the n satellites, provided the geographical location information meets the requirement of the monitoring station being stationary; obtaining a fixed ambiguity solution corresponding to the monitoring station based on the ambiguity search subset; and determining the geographical location coordinates of the monitoring station based on the fixed ambiguity solution. Compared to traditional ambiguity search methods, this method further improves the success probability of ambiguity search and the accuracy of the monitoring station's geographical location.