CN-121091330-B - Novel basic mapping equipment positioning method and system based on Beidou technology

CN121091330BCN 121091330 BCN121091330 BCN 121091330BCN-121091330-B

Abstract

The invention discloses a novel basic mapping equipment positioning method and system based on the Beidou technology, and relates to the technical field of mapping and positioning, wherein the method comprises the steps of receiving radio frequency signals of Beidou satellites and preprocessing position coordinates to generate baseband signals; demodulating and resolving based on the baseband signal to generate a complex-form observation signal, calculating a signal-to-noise ratio to perform validity detection and sampling verification, and obtaining a verification result, wherein the verification result comprises undersampling of a current sample and completeness of the current sample; when the current sample is undersampled, the instantaneous frequency set is extracted based on the baseband signal, a preliminary phase coefficient vector is generated, and the preliminary phase coefficient vector is subjected to feasible-infeasible judgment by combining a polynomial phase function and a residual error judgment mechanism.

Inventors

LU QIFENG
YANG WEI
LIAO JING
SHEN XUAN
ZHOU KEQING
Li Congtian
Jin Maojie
LI DENGCHAO
MENG JUNJUN
ZHAO SHUZHI
Lei Xiuhai
HUANG GUANGHUI
XIAO PIN
HUANG CHEN
LI YANG

Assignees

湖北省地质局第一地质大队

Dates

Publication Date: 20260505
Application Date: 20250915

Claims (9)

1. A novel basic mapping equipment positioning method based on Beidou technology is characterized by comprising the following steps of, Receiving radio frequency signals and position coordinates of a Beidou satellite for preprocessing, and generating baseband signals; demodulating and resolving based on the baseband signal to generate a complex-form observation signal, calculating a signal-to-noise ratio to perform validity detection and sampling verification, and obtaining a verification result, wherein the verification result comprises undersampling of a current sample and completeness of the current sample; Based on the baseband signals, respectively carrying out envelope demodulation and phase calculation to generate the amplitude and the phase of the baseband signals, taking the amplitude and the phase as observation signals, adding a time stamp, carrying out unified modeling on all the observation signals, obtaining the signal to noise ratio of the complex-form observation signals by utilizing a standard signal to noise ratio formula after generating the complex-form observation signals at different moments, carrying out validity detection, generating a detection result, and carrying out sampling verification according to the detection result; the validity detection is carried out again, a detection result is generated, namely a detection threshold value is set through related book knowledge and experiments, when the signal to noise ratio is smaller than the detection threshold value, the current signal is determined to be an invalid sample and is removed, and otherwise, the current signal is determined to be an valid sample and is reserved; The sampling verification means that the sampling number is set through the Nyquist sampling theorem, after the total number of reserved effective samples is counted, a ratio between the reserved effective samples and the sampling number is obtained through a proportion formula, the ratio is defined as a sampling ratio, a judgment threshold is set through a rule of thumb, when the sampling ratio is smaller than the judgment threshold, the current sample is considered to be undersampled, otherwise, the current sample is considered to be complete, and positioning calculation is directly carried out; when the current sample is undersampled, an instantaneous frequency set is extracted based on a baseband signal, a preliminary phase coefficient vector is generated, and the preliminary phase coefficient vector is subjected to feasible-infeasible judgment by combining a polynomial phase function and a residual error judgment mechanism; Based on a feasible result, performing correction operation to generate a final phase correction value vector, constructing a maximum likelihood criterion function, combining a hybrid optimization algorithm to update the final phase correction value vector, outputting an optimal correction vector, and performing positioning calculation according to the optimal correction vector to obtain a coordinate position and a clock difference of mapping equipment as positioning basis; the hybrid optimization algorithm refers to the mixture of a particle swarm optimization algorithm and an gravitation search algorithm.
2. The method for positioning the novel basic mapping equipment based on the Beidou technology of claim 1 is characterized in that the method is characterized in that a baseband signal is used for extracting an instantaneous frequency set, generating a preliminary phase coefficient vector, carrying out feasible-infeasible judgment on the preliminary phase coefficient vector by combining a polynomial phase function and a residual error judgment mechanism, framing the baseband signal by using a sliding window when a current sample is undersampled, carrying out time-frequency conversion on the baseband signal by using short-time Fourier transform under each frame to obtain a frequency variable under each frame of signal, carrying out maximization, generating instantaneous frequencies of each frame of signal at different moments, and recording time stamps; Integrating the instantaneous frequencies at different moments to form an instantaneous frequency set of a current baseband signal, generating random numbers by using a random number generator which is uniformly distributed, randomly selecting non-repeated instantaneous frequencies from the instantaneous frequency set according to the random numbers to generate an observation vector of the current baseband signal, integrating a timestamp corresponding to the instantaneous frequency into a regression matrix based on the selected instantaneous frequencies, and fitting the observation vector and the regression matrix by a least square method to generate a preliminary phase coefficient vector; Extracting preliminary phase coefficients in the preliminary phase coefficient vector, constructing a polynomial phase function, calculating a phase estimation value, solving a first-order time derivative according to the phase estimation value, defining the first-order time derivative as reconstruction frequency, constructing a reconstruction vector, solving a residual vector between the reconstruction vector and an observation vector by using element-by-element subtraction, and taking the Euclidean norm square value of the residual vector to carry out feasible-infeasible judgment on the preliminary phase coefficient vector.
3. The method for positioning a novel basic mapping device based on Beidou technology as set forth in claim 2, wherein the step of performing a correction operation to generate a final phase correction value vector based on a feasible result refers to performing a de-chirp operation on a baseband signal based on a feasible preliminary phase coefficient vector, generating a de-chirp signal, performing phase unwrapping to obtain unwrapped phase values, and performing stitching to generate a phase vector; Reconstructing a new regression matrix by using the time stamps of all instantaneous frequencies in the instantaneous frequency set, performing secondary regression by combining the phase vector to generate a correction vector, and summing by combining the primary phase coefficient vector to obtain a final phase correction value vector ; The total number of instantaneous frequencies in the instantaneous frequency set is counted before the secondary regression is performed And combining the total number of orders of the polynomial phase function Validating the new regression matrix when the total number When it is, it means that the verification is satisfied, a quadratic regression can be performed, otherwise the total number of orders of the polynomial phase function is calculated Adjusted to the total number And re-calculating the preliminary phase coefficient vector for re-verification.
4. The method for locating novel basic mapping equipment based on Beidou technology as set forth in claim 3, wherein updating the final phase correction value vector by combining the maximum likelihood criterion function with the hybrid optimization algorithm is based on the final phase correction value vector Extracting a final phase correction value, constructing a maximum likelihood criterion function, carrying out updating iteration, outputting candidate phase correction values after the iteration is carried out for the maximum times, and combining the candidate phase correction values to generate a candidate phase correction value vector; based on the candidate phase correction value vector, after being used as a particle individual, an initial speed and a position are randomly set for the particle individual in a uniformly distributed random mode, and a population is randomly generated for initialization; defining a modulus value of a maximum likelihood criterion function as an fitness function, calculating fitness values, and normalizing the maximum fitness values and the minimum fitness values in the calculation results of the fitness values by utilizing maximum and minimum operations to obtain the weight of each particle unit; Calculating the distance between any two particle individuals by using Euclidean distance, combining weights, calculating the gravitation between any two particle individuals by using a gravitation search algorithm, generating a uniformly distributed random number by using a random number generator, combining the gravitation, calculating the resultant force of each particle individual, and taking the ratio of the resultant force to the weights as an acceleration value; When the gravitation searching algorithm is used for calculating gravitation between any two particle individuals, selecting a maximum distance through a maximizing operation, calculating a gravitation constant initial value, and updating the gravitation constant initial value in an exponential decay mode; based on the acceleration value, the acceleration value is used as a disturbance term and added into a standard speed updating formula of the particle swarm optimization algorithm in a summation mode, updating and iterating of each particle individual position are carried out by utilizing a standard memorizing and collaborative updating mechanism, and after the iteration is carried out to the maximum number of times, the optimal correction vector is output.
5. The method for positioning a novel basic mapping device based on Beidou technology as set forth in claim 4, wherein the performing positioning calculation according to the optimal correction vector means that after extracting an optimal phase coefficient, a phase estimation value is recalculated through a polynomial phase function, a first-order time derivative is recalculated according to the phase estimation value, the first-order time derivative is defined as a new frequency, the new frequency is integrated by an integral accumulation method, a carrier phase observation value is obtained and converted, and a pseudo-range observation value of a Beidou satellite is generated; based on the position coordinates of the Beidou satellites, combining the pseudo-range observation values, generating positioning equations of all the Beidou satellites to form a positioning equation set, and carrying out iterative solution on the positioning equation set by using a least square method to obtain the coordinate position and clock difference of mapping equipment as positioning basis.
6. The method for positioning a novel basic mapping device based on Beidou technology as set forth in claim 5, wherein the receiving of radio frequency signals and position coordinates of Beidou satellites is preprocessed, and baseband signal generation means that a multi-frequency point antenna and a receiver are carried for the mapping device; The method comprises the steps of receiving radio frequency signals of the Beidou satellite through a multi-frequency point antenna, denoising, normalizing and down-converting to generate baseband signals of the Beidou satellite, receiving broadcast ephemeris of the Beidou satellite through a receiver, and acquiring position coordinates of the Beidou satellite from the broadcast ephemeris by using a GNSS Kepler orbit propagation method.
7. A novel basic surveying and mapping equipment positioning system based on the Beidou technology is characterized by comprising the following steps of, The processing verification module is used for receiving radio frequency signals and position coordinates of the Beidou satellite for preprocessing, generating baseband signals for demodulation and decoding, calculating signal-to-noise ratio for validity detection and sampling verification; The generation judging module is used for extracting an instantaneous frequency set and carrying out feasible-infeasible judgment by combining a polynomial phase function and a residual error judging mechanism; And the updating and resolving module is used for executing correction operation, constructing a maximum likelihood criterion function, combining with the hybrid optimization algorithm to update and execute positioning resolving.
8. The computer equipment comprises a memory and a processor, wherein the memory stores a computer program, and the computer equipment is characterized in that the processor realizes the steps of the novel basic mapping equipment positioning method based on the Beidou technology according to any one of claims 1-6 when executing the computer program.
9. A computer readable storage medium, on which a computer program is stored, is characterized in that the computer program, when being executed by a processor, implements the steps of the novel basic mapping device positioning method based on Beidou technology as set forth in any one of claims 1-6.

Description

Novel basic mapping equipment positioning method and system based on Beidou technology Technical Field The invention relates to the technical field of mapping and positioning, in particular to a novel basic mapping equipment positioning method and system based on the Beidou technology. Background With the rapid development of global satellite navigation systems (GNSS), satellite positioning and navigation techniques have been widely used in the fields of basic mapping, engineering construction, geographic information systems, unmanned measurement and control, and the like. The Beidou satellite navigation system (BDS) is taken as a global satellite navigation system autonomously constructed and operated in China, and has important value in the aspects of high-precision mapping and geographic information acquisition by virtue of the characteristics of multi-frequency points, global coverage, regional enhancement and the like. In the traditional GNSS mapping equipment positioning method, satellite orbit parameters are obtained by demodulating navigation messages through a receiver based on joint solution of code pseudo-range observation values and carrier phase observation values, and the position of the mapping equipment is solved by iteration of a pseudo-range equation. However, in a complex environment, the Beidou signal is easily affected by ionosphere, troposphere, multipath effect and shielding interference, so that the quality of the received signal is uneven, and the problems of low signal-to-noise ratio, incomplete sampling points, damaged phase continuity and the like exist. The uncertainty and noise interference severely restrict the reliability and robustness of high-precision mapping, so that the positioning precision of centimeter level and even sub-meter level is difficult to realize stably in undersampling and high-noise environment in the prior art. 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 novel basic mapping equipment positioning method and system based on the Beidou technology, which solve the problems that the reliability and robustness of high-precision mapping are severely restricted by uncertainty and noise interference in the prior art, so that the positioning precision of centimeter level or even sub-meter level is difficult to realize stably in undersampling and high-noise environment in the prior art. In order to solve the technical problems, the invention provides the following technical scheme: In a first aspect, the invention provides a novel basic mapping equipment positioning method based on Beidou technology, which comprises the steps of, Receiving radio frequency signals and position coordinates of a Beidou satellite for preprocessing, and generating baseband signals; demodulating and resolving based on the baseband signal to generate a complex-form observation signal, calculating a signal-to-noise ratio to perform validity detection and sampling verification, and obtaining a verification result, wherein the verification result comprises undersampling of a current sample and completeness of the current sample; when the current sample is undersampled, an instantaneous frequency set is extracted based on a baseband signal, a preliminary phase coefficient vector is generated, and the preliminary phase coefficient vector is subjected to feasible-infeasible judgment by combining a polynomial phase function and a residual error judgment mechanism; Based on a feasible result, performing correction operation to generate a final phase correction value vector, constructing a maximum likelihood criterion function, combining a hybrid optimization algorithm to update the final phase correction value vector, outputting an optimal correction vector, and performing positioning calculation according to the optimal correction vector to obtain a coordinate position and a clock difference of mapping equipment as positioning basis; the hybrid optimization algorithm refers to the mixture of a particle swarm optimization algorithm and an gravitation search algorithm. The invention relates to a novel basic mapping equipment positioning method based on Beidou technology, which comprises the following steps of demodulating and resolving based on a baseband signal to generate a complex-form observation signal, calculating a signal-to-noise ratio to perform validity detection and sampling verification, respectively performing envelope demodulation and phase resolving based on the baseband signal to obtain a verification result, generating the amplitude and the phase of the baseband signal, taking the amplitude and the phase as the observation signal, adding a timestamp, uniformly modeling all the observation signals, generating complex-form observation signals at different moments, acquiring the signal-to-noise ratio of the complex-form observation signal by using a standard signal-t