136 results about "Correction number" patented technology

The invention discloses a BDS/GPS high-accuracy positioning method, relating to the field of satellite navigation. The method includes establishing a virtual reference station, acquiring the common-view satellite ephemeris and the satellite observation data received by a reference station Bi and a roving station M, and acquiring the geometry distance between the satellite and the reference station Bi; acquiring the pseudo range correction number of the reference station Bi; interpolating the pseudo range correction number of the virtual reference station by means of an algorithm of inverse distance to a power; interpolating the pseudo range correction number of the roving station by the roving station by means of an algorithm of inverse distance to a power; correcting the satellite pseudo range observation data received by the roving station by means of the pseudo range correction number of the roving station; and establishing a roving station satellite pseudo range observation equation to obtain the accurate coordinate of the roving station to complete the positioning. According to the invention, the safety hidden troubles of information leakage of the reference station because a multi-reference difference positioning method in the prior art must use the accurate coordinate of the reference station can prevented, and high-accuracy positioning is obtained.

A memory controller that has an error correction number correspondence table that stores an error threshold level in correspondence with an error correction number; an error threshold level storage section that stores an error threshold level for each block; an uncorrected number measurement section that measures an uncorrected number of an error correction for each block; an error threshold level modification section that, each time an uncorrected number of a certain block exceeds a predetermined number, modifies the error threshold level of the block; an encoder that performs encoding processing of data stored in memory cells belonging to each block with an error correction number that is based on an error threshold level and the error correction number correspondence table; and a decoder that performs decoding processing of data.

The invention relates to the technology of communication, and discloses a differential relay method and device for a global navigation satellite system. According to the invention, the method comprises the steps: enabling a transmission region of a server to be divided into a plurality of grid units, setting at least one differential relay in each grid unit; calculating a difference correction number of each differential relay through the server, and transmitting the position information of each relay and the difference correction numbers to a user terminal, so that the user terminal employs the position information and the difference correction number of the differential relay nearest to the user terminal for differential positioning, thereby facilitating the use of differential services. Moreover, the server can meet the demands of a large number of users only if the server calculates a fixed number of difference correction numbers, thereby improving the coverage and usability of the differential services. In addition, the user terminal does not need to upload the position information of the user terminal to the server, can carry out differential positioning through obtaining the difference correction number of the nearest differential relay according to the position information of each differential relay, and guarantees the crypticity of a user.

The invention discloses a continuous operational reference system (CORS) base station cycle slip detection and recovering method, which comprises the following steps that: firstly, an ionized layer residual method is used for carrying out cycle slip detection, a satellite with the cycle slip and the corresponding observation value are determined, then, a single-epoch dual-frequency observation equation is built according to the cycle slip detection results, the single-epoch dual-frequency observation equation is divided into two types, the first type is cycle-slip-free observation equations, the second type is cycle slip observation equations, the cycle slip generated by a non-reference satellite is used as a gross error, the cycle slip generated by a reference satellite is used as a system error, the first type observation equations are used for carrying out parameter estimation, the cycle slip of the reference satellite is determined, the estimated parameters are introduced into thesecond type observation equations, correction numbers are calculated, the cycle slip values of the reference satellite are obtained, and finally, the cycle slip base station observation data is recovered according to the relationship between the base lines in a CORS triangular net. Because the error time strong correlation of the precise coordinate, the dual-frequency convection layer, the ionized layer and the like is directly utilized, the cycle slip detection and recovery can be precisely carried out.

A motor controller of the sort having both a transformation function for transforming three-phase feedback information into two components, and then changing an error signal for each of the two components back into three-phase correction numbers is provided with an ARCTAN correction function. The ARCTAN correction function takes in the time derivative of the changing angular position of the motor rotor, and creates a correction factor that is supplied back to the transformation function for changing the two error signals back into three. By supplying this correction ARCTAN function, the control eliminates a disturbance that may have occurred in the prior art at higher frequencies wherein both of the control loops for the two components needed to come into play to correct an error on either of the two loops.

The invention discloses an error-separation-mode-based regional pseudo-range differential enhanced positioning method of a global navigation satellite system (GNSS). The method comprises: for regional pseudo-range differential enhanced positioning of a GNSS, n reference stations and a terminal user are employed; a receiver of any reference station r receives observation data of a satellite s, and after processing, an error vector correction number of the satellite s on the reference station r is obtained; each reference station sends the obtained error vector correction number of the satellite s to the terminal user, distance weighted mean processing is carried out on a frequency relevant item error correction number of each reference station according to a base line distance between the reference station and the terminal user, and then the processed number adds to a frequency non-relevant item error correction number of one reference number to obtain a total error correction number; and then a pseudo-range measurement value adds to the total error correction number to obtain a corrected user pseudo range and then calculation is carried out according to a standard pseudo-range single-point positioning way so as to obtain a user position after error correction. With the method, the positioning performance of the single-frequency satellite navigation can be improved.

The invention, which relates to the field of satellite positioning, provides a wide-area differential positioning method, apparatus, and terminal, and a computer-readable storage medium. The method comprises: a differential positioning request sent by a user terminal is received, wherein the differential positioning request carries initial positioning information of the user terminal and feature information corresponding to a data format that can be received by a receiver of the user terminal; a wide-area differential correction number meeting a preset condition is obtained from a database; and according to the initial positioning information and the wide-area differential correction number meeting the preset condition, a positioning correction number of the user terminal is calculated, wherein the format of the positioning correction number corresponds to the feature information. Because the positioning correction number that can be received by the receiver of the user terminal is calculated based on the initial positioning information and the wide-area differential correction number, the user terminal is able to carry out positioning accurately by using the positioning correctionnumber without any modification on the user terminal, so that the positioning accuracy of the user terminal is improved with low costs.

The invention discloses a precise positioning method through combination of a single-frequency GPS and GLONASS and a device thereof. The method includes: establishing a base station and a mobile station, wherein a positioning module includes a single-frequency GPS chip and a single-frequency GLONASS chip. The base station and the mobile station reading broadcast ephemerises output by positioning modules of the base station and the mobile station respectively; the base station and the mobile station carrying out time synchronization on a GLONASS and a GPS respectively; the base station and the mobile station calculating satellite positions of the GPS and the GLONASS respectively according to the ephemerises of the positioning modules of the base station and the mobile station; the mobile station and the base station reading original pseudo-range data respectively; the base station calculating a pseudo-range difference correction number of the base station according to the position of the base station, the acquired satellite positions of the GPS and the read GLONASS and the read original pseudo-range data output by the GPS and the GLONASS chip; and the mobile station calculating a positioning result through adoption of a Kalman filtering method according to the acquired satellite positions, read original pseudo-range phase data output by the GPS and the GLONASS chips and the pseudo-range difference correction number obtained from the base station. Therefore, calculation is stable and positioning is accurate.

Disclosed are a satellite positioning method and a satellite positioning system. The system includes satellites, a base station, and an observation station. A monitoring terminal and a correction parameter information generation device are arranged at the observation station. The monitoring terminal receives observation data transmitted from the satellites. The correction parameter information generation device generates correction parameters based on the observation data, and the correction parameters are sent to the base station. The base station is provided with a switch and a message parameter overlay, coding and broadcasting device. The switch receives basic navigation messages from the satellites. The message parameter overlay, coding and broadcasting device programs the correction parameters through protocol overlay to the basic navigation messages, and sets the broadcasting of an integrated code message that incorporates the correction parameters. The code message is sent fromthe switch to the satellites through an uplink injection link. The satellites broadcast the integrated code message received from the base station. The correction parameters include one or more of thesub-region comprehensive correction number, the satellite orbit correction number, the satellite clock correction number, and the ionosphere correction number.

The invention relates to a Beidou/GPS dual-mode navigation positioning device and method, and the method comprises the steps: receiving a Beidou/GPS satellite signal, and reading satellite data; analyzing and calculating the satellite data, obtaining a first Beidou/GPS difference correction number, and storing the first Beidou/GPS difference correction number at a reference station; receiving a Beidou/GPS satellite signal and reading the satellite data; carrying out the analyzing and calculation of the satellite data, and obtaining a second Beidou/GPS difference correction number; carrying out the matching and correction of the first and second Beidou/GPS difference correction numbers, obtaining a corrected Beidou/GPS difference correction number, carrying out the position analysis, and carrying out the dual-mode positioning; and enabling an airborne moving station to carry out the continuous positioning. Compared with the prior art, the method can improve the positioning speed and precision. The method also can achieve the continuous positioning under the condition of no satellite signal, and improves the positioning precision.

The invention relates to a method for realizing positioning based on a Beidou short message transmission differential signal. The method is provided in order to improve the applicability of satellite differential positioning, and is used to perform differential positioning in an area with neither network base station nor mobile communication base station. The method comprises the following steps: a reference station terminal gets a differential correction number according to a received satellite signal and the coordinate of a reference station, and stores the differential correction number in an internal memory of the reference station terminal; a moving station terminal generates a differential data request including differential start time and differential frequency, and sends the differential data request to the reference station terminal; the reference station terminal sends corresponding differential data to a reference station coding module after receiving the differential data request sent by the moving station terminal; the reference station terminal sends a single piece of differential data information through a Beidou short message, and multiple cards send differential data information in turn to meet the requirement of the moving station terminal for positioning frequency; and the moving station terminal receives differential data of multiple epochs, uses the data to fit a pseudo-range differential correction number through Chebyshev polynomial interpolation, and uses a correction number obtained by extrapolation to perform differential positioning.

The present application relates to a positioning method and device, a computer device and a storage medium. The method includes the steps of: when signal interruption with a reference station is detected, acquiring the current observed data received by a mobile station in a current epoch, the historical observed data received by the mobile station in a neighboring historical epoch, and the correction number of a stationary orbit satellite; subjecting the neighboring historical coordinate position, the current observed data, the historical observed data, and the correction number to differential single-point positioning process to obtain the current position of the mobile station. The positioning method provided by the present application can achieve accurate positioning in the case of signal interruption.

The invention provides an analog-to-digital converter (ADC). The ADC comprises a plurality of stages connected in series, a gain error correction module, and a look-ahead module. Each of the stages derives a stage output value from a stage input signal and generates a stage output signal as the stage input signal of a subsequent stage, wherein one of the stages is selected as a target stage for estimating a gain value thereof. The gain error correction module delivers a correction number to the target stage to affect the stage output signal of the target stage and the stage output values of subsequent stages of the target stage, receives at least one auxiliary output value from a look-ahead module dedicated to the target stage, and derives an error estimate of the gain value of the target stage from the stage output values and the auxiliary output value. The look-ahead module generates the auxiliary output value according to the stage output value of the target stage, wherein the auxiliary output value is not affected by the correction number.

The invention provides an unmanned aerial vehicle multi-frame image self-adaptive positioning and correcting method based on aerial photography attitudes, and belongs to the technical field of remote sensing image processing. The method comprises the main steps that firstly, self-adaptive initialization is carried out, wherein different initialization strategies are used for different sources of multi-frame images, and different initial values are selected for different flight attitudes; secondly, the number of correspondingly required homonymy points is determined according to the number of input image frames; thirdly, an error equation is established by utilizing constraint conditions between the images by utilizing the bundle adjustment method, all the homonymy points of each image are traversed, and a normal equation is established; fourthly, a correction number is added to an approximate value to serve as a new approximate value for iteration till the correction number is smaller than a limit value, and the correction number is output. Error correction is conducted on the acquired images with the common region accurately in real time in the online aerial photography process of an unmanned aerial vehicle, and the accuracy of a positioning result is improved.

The invention discloses a compensation elevation plane or mean elevation plane-based 3-degree zoning coordinate conversion system. By research on a geodetic coordinate change law of a control point ona reference ellipsoid, a compensation elevation plane or a testing zone and a mean elevation plane of a city, a calculation method for a semi-major axis of a new ellipsoid after adoption of the compensation elevation plane or the testing zone and the mean elevation plane of the city, a calculation method for a geodetic latitude correction number and new geodetic latitude of the ground control point, and a calculation method for calculating direct and inverse computation parameters by taking the compensation elevation plane or the testing zone, the mean elevation plane of the city, the semi-major axis of the ellipsoid and first eccentricity as arguments are derived. Compared with the prior art, the control point is transferred to the compensation elevation plane or the testing zone and themean elevation plane of the city from the CGCS2000 ellipsoid according to calculation formulae for the direct and inverse computation parameters; high-precision coordinate conversion of geodetic coordinates and plane coordinates can be realized; and a conversion mode is also suitable for a 1980 Xi an coordinate system, a 1954 Beijing coordinate system and local independent coordinate systems.

The present invention discloses a position correction method based on a CORS (Continuously Operating Reference Station), a positioning terminal and a positioning system. The position correction methodcomprises the following steps of: the step 1: establishing an irregular grid model: performing mutual connection of each three nearest CORSs to form one triangle, and forming an irregular grid modelby employing the plurality of triangles; and the step 2: matching a corresponding triangle according to outline coordinates (x, y, z) provided by a position service request terminal, namely determining that which three CORSs form the triangle where the position service request terminal is located, calculating coordinate correction numbers ([Alpha]m, [Beta]m, [Gamma]m) according to the coordinate difference of the three CORSs at a corresponding moment, and finally obtaining a corrected position coordinate value (x+[Alpha]m, y+[Beta]m, z+[Gamma]m) of the position service request terminal. The position correction method based on CORS, the positioning terminal and the positioning system can substantially improve the positioning precision and are easy to carry out.

The invention provides a free station setting method based on overall disc position measurement, aiming at effectively improving the elevation station setting precision and meeting free station setting requirements so as to improve the station setting efficiency and the station setting stability. The free station setting method comprises the following steps: (1) selecting a proper position; erecting a total station and then leveling; (2) manually aiming at two back-sight points and then carrying out the overall disc position measurement on the back-sight points needing to be observed; (3) calculating a direction value, a distance, a vertical angle and a vertical disc index error; then carrying out three-dimensional compensating computation to obtain coordinates, precision and coordinate azimuth angles of station setting points; (4) carrying out constant weight iterative computation again according to a correction number until weight is not changed any more; outputting the coordinates,the precision and the coordinate azimuth angles of the station setting points, which are obtained by the three-dimensional compensating computation, of the station setting points; and (5) after the station setting is finished, carrying out vertical disc index error correction when a front-sight point is measured through a single disc position and then calculating a three-dimensional coordinate ofthe point.

The invention discloses an orthorectification method based on geometric model of linear array push-scan asynchronous-sampling satellite image, which adopts a projective mode of double centre line projection to describe the geometrical deformation law of a linear array push-scan asynchronous-sampling satellite image; by recovering all parameters of the double centre line projection, the relationship between pixel coordinates of the satellite image and corresponding ground coordinates is established, thus realizing the orthorectification based on geometric model of linear array push-scan asynchronous-sampling satellite image; the method comprises the following steps of: (1) determining initial value of model parameters of the double centre line projection; (2) calculating error equation coefficients and resolving correction numbers of model parameters; (3) calculating a range outputting orthorectific image; (4) calculating the interpolating calculation of the gray value of grid points of the orthorectific image.

The invention discloses a high-frequency epoch-by-epoch phase difference method for single-frequency GNSS phase stability monitoring, comprising the following steps: using a single-frequency GNSS receiver to perform high-frequency observation on a station point, and calculating the phase difference between adjacent epochs; using the least squares method to detect a station 3D (NEU) coordinate correction number time series within the interval of adjacent epochs under continuous epochs; getting the mean and standard deviation of the NEU coordinate through statistical analysis of the time series; and calculating the anomaly ratio. The phase observation stability of the single-frequency GNSS receiver is evaluated by calculating the continuous observation anomaly ratio using the method. Single-point real-time high-frequency GNSS phase data quality monitoring is carried out based on single-frequency GNSS data. The GNSS phase stability can be evaluated without the need for high-precision clock difference or model correction.