Method and device for geophysical prospecting measurement navigation and positioning in region without RTK (Real-Time Kinematic) signal

Abstract

The invention discloses an RTK signal-free area geophysical prospecting measurement navigation and positioning method and device, and belongs to the technical field of satellite navigation and positioning. The method comprises the steps that S1, a reference station, a moving station and a front reference station are erected, observation data of the reference station, the moving station and the front reference station are recorded, and the distance between the front reference station and the moving station is kept to be smaller than 10 km; s2, setting conversion parameters between ITRF frames, converting pseudo-range single-point positioning coordinates into local ITRF frame coordinates, and performing geophysical prospecting navigation by using pseudo-range single-point positioning; and S3, downloading observation data of the reference station, the moving station and the front reference station, carrying out post-processing, obtaining coordinates of a moving station track at a corresponding moment, and carrying out geophysical prospecting positioning. The invention provides a novel navigation and positioning method for petroleum geophysical prospecting measurement in a region without RTK differential signals, and the construction efficiency is improved while the precision requirement of the petroleum geophysical prospecting measurement is met.

Description

Technical Field

[0001] The invention belongs to the technical field of satellite navigation and positioning, and relates to a method for navigation and positioning in an area without RTK differential signals, and specifically to a method and device for geophysical surveying navigation and positioning in an area without RTK signals. Background Art

[0002] Petroleum geophysical survey is divided into two parts: layout and measurement. Layout refers to navigating the point to the designed point in real time with sub-meter accuracy; measurement refers to accurately measuring the actual point with centimeter accuracy.

[0003] RTK technology is a real-time dynamic positioning technology, and its specific principle is dynamic carrier phase difference. RTK operation requires that the original data of the reference station be sent to the mobile station in real time through a radio or network. The mobile station receives the reference station data and performs carrier phase difference with the original data of the mobile station to obtain the real-time centimeter-level coordinates of the mobile station.

[0004] In petroleum geophysical surveying, RTK is usually used as a navigation and positioning method to meet the requirements of navigation and positioning accuracy. However, due to the obstruction of mountains, sand dunes, etc., there is no RTK differential signal in some areas, the data of the reference station cannot be transmitted to the mobile station in real time, and the RTK technology cannot be used. The usual solution is to set up a relay station or relocate the reference station, but this will reduce construction efficiency.

[0005] PPK technology is a dynamic post-processing technology, and its specific principle is dynamic carrier phase differential. Compared with RTK, PPK does not need to transmit the reference station data to the mobile station in real time, so there is no data link radio, and there is no need to wait for initialization, which provides great convenience for point measurement. And because of the use of post-processing, there are more ways to process data, which will get more accurate processing results. However, since PPK technology records observation data for post-processing, it cannot navigate in real time and cannot be used for the layout part of petroleum geophysical survey.

[0006] Pseudorange single-point positioning is a method of navigation and positioning that uses dual-frequency pseudorange to eliminate the influence of the ionosphere. It uses multi-system pseudorange positioning, and its plane navigation accuracy is less than 3 meters, which cannot meet the accuracy requirements of layout and measurement in petroleum geophysical exploration. Summary of the invention

[0007] The purpose of the present invention is to provide a method and device for geophysical survey navigation and positioning in areas without RTK signals, so as to solve the problem that oil geophysical survey cannot be accurately performed without using RTK technology in areas without RTK differential signals.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is:

[0009] A method for geophysical surveying navigation and positioning in an area without RTK signals, comprising the following steps:

[0010] S1. Set up reference stations, mobile stations and pre-reference stations, record the observation data of reference stations, mobile stations and pre-reference stations, and keep the distance between pre-reference stations and mobile stations less than 10km;

[0011] S2. Set the ITRF (International Terrestrial Reference Frame) frame conversion parameters, convert the pseudo-range single-point positioning coordinates to the local ITRF frame coordinates, and use the pseudo-range single-point positioning for geophysical navigation;

[0012] S3. Download the observation data of the reference station, mobile station and pre-reference station and perform post-processing to obtain the coordinates of the mobile station trajectory at the corresponding time and perform geophysical positioning.

[0013] As a limitation, the post-processing in step S3 specifically includes:

[0014] The coordinates of the front reference station are obtained based on the observation data of the reference station and the front reference station; the coordinates of the mobile station trajectory are obtained based on the observation data of the front reference station and the mobile station; and the coordinates of the mobile station trajectory at the corresponding time are intercepted according to the recording time of the measurement point of the mobile station.

[0015] As a further limitation, the coordinates of the front reference station are obtained based on the observation data of the reference station and the front reference station, using a static carrier relative positioning method;

[0016] The coordinates of the mobile station trajectory are obtained based on the observation data of the front reference station and the mobile station, and the dynamic carrier relative positioning method is adopted.

[0017] As another limitation, the step S2 of converting the pseudorange single point positioning coordinates into the local ITRF frame coordinates specifically includes:

[0018] S21. Convert the WGS84 reference frame (aligned with the ITRF2008 reference frame, with the epoch being the current epoch) to the ITRF2008 reference frame, epoch 2010.0, and use the point velocity obtained by interpolation after gridding the high-precision continental drift velocity field model of my country;

[0019] S22. Use the inter-frame conversion parameters published by IERS (International Earth Rotation and Reference Systems Service) to convert the ITRF2008 reference frame, 2010.0 epoch coordinates to the local ITRF reference frame, 2010.0 epoch. The conversion model is the Bursha seven-parameter model.

[0020] S23. The local ITRF reference frame and the 2010.0 epoch are converted to the local ITRF reference frame and the local reference frame epoch. The point velocity is obtained by interpolating the gridded high-precision continental drift velocity field model of my country.

[0021] As a third limitation, the observation data includes pseudorange, carrier and signal-to-noise ratio.

[0022] The present invention also discloses a device for geophysical surveying, navigation and positioning in an area without RTK signals, comprising:

[0023] Data acquisition module, used to acquire observation data from reference stations, mobile stations and front reference stations;

[0024] The geophysical exploration navigation module is used to set the conversion parameters between ITRF frames, convert the pseudo-range single-point positioning coordinates to the local ITRF frame coordinates, and use the pseudo-range single-point positioning for geophysical exploration navigation;

[0025] The geophysical positioning module is used to download the observation data of the reference station, mobile station and front reference station and perform post-processing to obtain the coordinates of the mobile station trajectory at the corresponding time and perform geophysical positioning.

[0026] Due to the adoption of the above technical solution, the present invention has the following technical advances compared with the prior art:

[0027] ① The method and device for geophysical survey navigation and positioning in an area without RTK signals provided by the present invention provide a new method for geophysical survey navigation and positioning in an area without RTK differential signals. While meeting the accuracy requirements of geophysical survey, there is no need to wait for the establishment of relay stations or the relocation of reference stations, and normal construction is carried out, thereby improving construction efficiency.

[0028] ② The method and device for geophysical surveying navigation and positioning in an area without RTK signals provided by the present invention sets up a front reference station near the mobile station, first calculates the coordinates of the front reference station using a high-precision static carrier relative positioning method, and then indirectly calculates the coordinates of the mobile station trajectory through the front reference station. Since the front reference station is close to the mobile station, the success rate of the solution is high, and the accuracy of the calculation result can reach the centimeter level;

[0029] ③ The method and device for geophysical surveying navigation and positioning in an area without RTK signals provided by the present invention can improve the navigation accuracy of the pseudo-range single-point positioning technology by setting the conversion parameters between ITRF frames to convert the pseudo-range single-point positioning coordinates into the local ITRF frame coordinates. After eliminating the differences between ITRF frames, the planar accuracy of the pseudo-range single-point positioning can reach less than 2 meters.

[0030] The present invention proposes a new navigation and positioning method for petroleum geophysical survey in an area without RTK differential signals, which improves construction efficiency while meeting the accuracy requirements of petroleum geophysical survey. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a flowchart of the method for geophysical surveying, navigation and positioning in an area without RTK signals in an embodiment. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below by specific examples. It should be understood that the described examples are only used to explain the present invention, and are not intended to limit the present invention.

[0033] Embodiment Method and device for geophysical survey navigation and positioning in area without RTK signal

[0034] This embodiment discloses a method for geophysical survey navigation and positioning in an area without RTK signals. The method is applied in a petroleum geophysical exploration research area in the loess plateau. Since there are mountains and gullies in the research area, there are many areas without RTK differential signals. The flowchart of the method is as follows: Figure 1 As shown, the specific steps include:

[0035] S1. Set up reference stations, mobile stations and pre-reference stations. The reference station is required to be set up at a known point, and to be centered, leveled, and the instrument height measured; the pre-reference station can be set up anywhere with an open area less than 10 km from the mobile station, and only needs to be leveled. During the entire geophysical survey, the pre-reference station does not need to be moved within 10 km of the mobile station; when the distance to the mobile station exceeds 10 km, it needs to be relocated closer to the mobile station to keep the distance between the pre-reference station and the mobile station less than 10 km.

[0036] The reference station, mobile station and pre-reference station are required to record the original observation data including dual-frequency carrier, dual-frequency pseudorange and signal-to-noise ratio, and set the epoch interval to 1s.

[0037] S2. Use pseudo-range single-point positioning for geophysical exploration navigation. Set the conversion parameters from WGS84 to the local coordinate system in the handheld navigation software. The conversion method is: S21. Conversion between epochs in the same ITRF reference frame: convert the WGS84 reference frame (aligned with the ITRF2008 reference frame, the epoch is the current epoch) to the ITRF2008 reference frame, 2010.0 epoch, and the point velocity is the point velocity obtained by interpolation after gridding the high-precision continental drift velocity field model of my country;

[0038] S22. Perform ITRF reference frame conversion at the epoch where the conversion parameters are located, and convert to the target frame: use the frame conversion parameters published by IERS (International Earth Rotation and Reference Systems Service) to convert the ITRF2008 reference frame, epoch 2010.0 coordinates to the local ITRF reference frame, epoch 2010.0, and the conversion model is the Bursha seven-parameter model;

[0039] S23. The target frame and the epochs where the conversion parameters are located are converted between epochs under the same ITRF reference frame and converted to the target frame and epochs: the local ITRF reference frame and the 2010.0 epoch are converted to the local ITRF reference frame and the local reference frame epochs. The point velocity is the point velocity obtained by interpolation after gridding using my country's high-precision continental drift velocity field model.

[0040] After the above conversion, the systematic difference between ITRF reference frames is eliminated, and pseudo-range single-point positioning is used for geophysical navigation.

[0041] The conversion formula for different epochs in the same frame in step S21 is as follows:

[0042]

[0043] Among them, [V X V Y V Z ] T is the displacement velocity of the point, and the point velocity is obtained by hyperbolic interpolation after gridding of my country's high-precision continental drift velocity field model; t1 is the instantaneous epoch; t0 is the target epoch (if the conversion parameters from ITRF2014 framework to other frameworks are used, t0 here is 2010.0).

[0044] The formula of the Bursa seven-parameter model used to calculate the conversion between ITRF reference frames in step S22 is as follows:

[0045]

[0046] Where [XYZ] T is the frame coordinate; [T X T Y T Z ] T is the frame transformation translation, R X , R Y , R Z They are the rotation amounts in the X, Y, and Z directions respectively; D is the scale ratio.

[0047] S3. Download the observation data of the reference station, mobile station and front reference station and perform post-processing: the observation data of the reference station and the front reference station are applied to the static carrier relative positioning method to obtain the coordinates of the front reference station (millimeter level); the observation data of the front reference station and the mobile station are applied to the dynamic carrier relative positioning method to obtain the coordinates of the mobile station trajectory (centimeter level); according to the recording time of the measurement point of the mobile station, the coordinates of the mobile station trajectory at the corresponding time are intercepted to perform geophysical positioning.

[0048] Among them, the tropospheric correction model of the static carrier relative positioning method is VMF3_GPT3 (Vienna Mapping Function 3_Global Pressure and temperature 3, Vienna mapping function 3_global pressure and temperature model 3) model;

[0049] The dynamic carrier relative positioning method (PPK technology) uses VMF3_GPT3 as the tropospheric correction model, the parameter estimation method is Kalman filtering, and the integer ambiguity search method is LAMBDA (Leastsquare AMBiguity Decorrelation Adjustment-LAMBDA). The specific steps are as follows:

[0050] Forward Kalman filter processing, integer ambiguity back-substitution, reverse Kalman filter processing, integer ambiguity back-substitution.

[0051] PPK, like RTK, requires initialization (floating-point solution of integer ambiguities), but PPK technology allows that after the integer ambiguities are fixed (integer ambiguity fixed solution), it can be substituted back to the epoch where the fixed solution was not obtained before, calculate the uninitialized coordinates, and accurately obtain the fixed solution before initialization.

[0052] The geophysical navigation and positioning method provided in this embodiment complies with the requirements of "SY / T 5171-2020 Specification for Onshore Petroleum Geophysical Survey".

[0053] The present invention also discloses a device for geophysical surveying, navigation and positioning in an area without RTK signals, comprising:

[0054] Data acquisition module, used to acquire observation data from reference stations, mobile stations and front reference stations;

[0055] The geophysical exploration navigation module is used to set the conversion parameters between ITRF frames, convert the pseudo-range single-point positioning coordinates to the local ITRF frame coordinates, and use the pseudo-range single-point positioning for geophysical exploration navigation;

[0056] The geophysical positioning module is used to download the observation data of the reference station, mobile station and front reference station and perform dynamic post-processing to obtain the coordinates of the mobile station trajectory at the corresponding time and perform geophysical positioning.

Claims

1. A method for geophysical surveying navigation and positioning in an area without RTK signals, characterized in that: The following steps are involved: S1. Set up reference stations, mobile stations and pre-reference stations, record the observation data of reference stations, mobile stations and pre-reference stations, and keep the distance between pre-reference stations and mobile stations less than 10km; S2. Set the conversion parameters between ITRF frames, convert the pseudo-range single point positioning coordinates to the local ITRF frame coordinates, and use the pseudo-range single point positioning for geophysical navigation; S3. Download the observation data of the reference station, mobile station and pre-reference station and perform post-processing to obtain the coordinates of the mobile station trajectory at the corresponding time and perform geophysical positioning.

2. The method for geophysical surveying, navigation and positioning in an area without RTK signals according to claim 1, characterized in that: The post-processing in step S3 specifically includes: The coordinates of the front reference station are obtained based on the observation data of the reference station and the front reference station; the coordinates of the mobile station trajectory are obtained based on the observation data of the front reference station and the mobile station; and the coordinates of the mobile station trajectory at the corresponding time are intercepted according to the recording time of the measurement point of the mobile station.

3. The method for geophysical surveying, navigation and positioning in an area without RTK signals according to claim 2, characterized in that: The coordinates of the front reference station are obtained based on the observation data of the reference station and the front reference station, and a static carrier relative positioning method is adopted; The coordinates of the mobile station trajectory are obtained based on the observation data of the front reference station and the mobile station, and the dynamic carrier relative positioning method is adopted.

4. The method for geophysical surveying, navigation and positioning in an area without RTK signals according to any one of claims 1 to 3, characterized in that: The step S2 of converting the pseudorange single point positioning coordinates into the local ITRF frame coordinates specifically includes: S21. The WGS84 reference frame is converted to the ITRF2008 reference frame and the 2010.0 epoch. The point velocity is obtained by interpolation after gridding using the high-precision continental drift velocity field model of my country. S22. Using the inter-frame conversion parameters published by IERS, the ITRF2008 reference frame, 2010.0 epoch coordinates are converted to the local ITRF reference frame, 2010.0 epoch, and the conversion model is the Bursha seven-parameter model; S23. The local ITRF reference frame and the 2010.0 epoch are converted to the local ITRF reference frame and the local reference frame epoch. The point velocity is obtained by interpolating the gridded high-precision continental drift velocity field model of my country.

5. The method for geophysical surveying, navigation and positioning in an area without RTK signals according to any one of claims 1 to 3, characterized in that: The observation data includes pseudorange, carrier and signal-to-noise ratio.

6. A device for geophysical surveying, navigation and positioning in areas without RTK signals, characterized in that: include: Data acquisition module, used to acquire observation data from reference stations, mobile stations and front reference stations; The geophysical exploration navigation module is used to set the conversion parameters between ITRF frames, convert the pseudo-range single-point positioning coordinates to the local ITRF frame coordinates, and use the pseudo-range single-point positioning for geophysical exploration navigation; The geophysical positioning module is used to download the observation data of the reference station, mobile station and front reference station and perform post-processing to obtain the coordinates of the mobile station trajectory at the corresponding time and perform geophysical positioning.

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