Laboratory playback calibration method and equipment for global navigation satellite system recorded data

Abstract

The present invention proposes a laboratory playback calibration method and equipment for recorded data of a global navigation satellite system. The method objectively compares the GNSS signal power levels reported by the NMEA messages of a reference receiver in an actual scene within the same time period with the NMEA messages of the same receiver in the playback scene, so as to obtain the calibration data required for the playback environment when the signal levels of the two scenes are maximally close to each other; the maximum approximation degree is calculated by considering multiple factors including the distribution characteristics of C / No, maximum power, minimum power, average power and other correlation coefficients; the coefficient of the maximum approximation degree can be changed according to the focus of different scenes; through the present invention, the laboratory playback restoration of recorded data can be objectively and accurately realized, and the calibration data can be traced; the GNSS signal power level is maximally close to the desired recording scene, and it is more possible for the laboratory to replace the road test work.

Description

Technical Field

[0001] The present invention relates to the technical field of data calibration, and in particular to a method, device, equipment and storage medium for laboratory playback calibration of recorded data of a global navigation satellite system. Background Art

[0002] Generally, in the positioning accuracy performance test of GNSS receivers, the method of recording live network data and then playing it back in the laboratory has been widely used. The method of recording GNSS RF data from the live network and playing it back in the laboratory can replace large-scale and inefficient live network testing, which can greatly reduce testing costs and improve testing efficiency.

[0003] However, in order to get as close as possible to the GNSS RF scenario when the data was recorded, and taking into account objective factors such as the playback environment and antenna gain, it is necessary to calibrate the playback signal in a laboratory playback environment, so that the overall level of the GNSS playback signal can be close to the GNSS signal level during recording.

[0004] At present, the method for comparing the GNSS signal levels recorded during laboratory playback with those during actual recording is mainly to observe the consistency of the strongest satellite power levels at approximately the same time to basically determine the approximate test environment. There is no objective and unified algorithm to calibrate the overall playback GNSS signal data.

[0005] Currently, the laboratory replays GNSS signal data mainly by observing whether the power level of the strongest GNSS satellite signal at the approximate time is close to the strongest GNSS signal level at the same time of recording, and then approximating it by adjusting the signal amplifier or attenuator. As a signal calibration method for setting up a laboratory test environment, the method of observing the approximate proximity of the signal has major problems:

[0006] Laboratory test equipment and environmental calibration must be objective, accurate, and traceable, but observation methods are subjective and cannot be traced.

[0007] It can only reflect the power level calibration of the strongest signal at a moment but not the entire signal playback process;

[0008] The strongest signal can only be focused on the strongest satellite signal level of a certain frequency band constellation, which is close to the strongest satellite signal level during recording. It is impossible to provide objective feedback on the playback signal level of all recorded constellation frequency bands. Summary of the invention

[0009] The present invention provides a method, device, equipment and storage medium for laboratory playback calibration of recorded data of a global navigation satellite system, aiming to improve the measurement and statistical efficiency during the construction and calibration of a laboratory playback environment.

[0010] To this end, a first object of the present invention is to provide a global navigation satellite system recorded data laboratory playback calibration method, comprising:

[0011] Set up a full-band full-constellation reference receiver and a GNSS signal recording device to synchronize NMEA message recording;

[0012] The distribution and power level of the constellation are counted for the reference NMEA messages generated by the GNSS signal recording device and the NMEA messages of the full-band and full-constellation reference receiver in the playback environment;

[0013] Based on the constellation population distribution and power level, the lowest approximation factor is determined, and the GNSS recorded data is calibrated based on the lowest approximation factor.

[0014] Among them, in the step of performing the distribution of the number of star clusters, the distribution statistics of the number of star clusters are simultaneously performed on the reference NMEA message and the NMEA message of the same reference receiver in the playback environment, and the number of star clusters is separated according to the star cluster frequency band, and the maximum power, minimum power, and average power of the carrier-to-noise ratio C / No of each star cluster frequency band are calculated at the same time.

[0015] Among them, in the step of determining the lowest approximation coefficient, the reference message is identified as File1, the calibrated environment message is identified as File2, the statistical distribution results of the different constellation frequency bands of the two NMEA files (DIST1, DIST 2, ..., DIST(n)), and the maximum power (MAX1, MAX2, ..., MAX(n)), the minimum power (MIN1, MIN 2, ..., MIN(n)) and the average power (AVG1, AVG 2, ..., AVG(n)) of the distribution are used as algorithm output parameters to calculate the approximation coefficient N.

[0016] Wherein, based on the maximum power, the minimum power and the average power, the distribution coefficient D, the minimum power coefficient S, the maximum power coefficient M, and the average power coefficient A are determined.

[0017] Among them, the distribution coefficient D, minimum power coefficient S, maximum power coefficient M, and average power coefficient A are expressed as follows:

[0018]

[0019]

[0020]

[0021]

[0022] Among them, the formula for the minimum approximation coefficient N is expressed as:

[0023] N=f1*D+f2*S+f3*M+f4*A

[0024] Among them, f1, f2, f3, and f4 are weight coefficients, which are modified according to the focus.

[0025] Among them, a preset expected value is set, and the lowest approximation coefficient N is compared with the preset expected value. If the lowest approximation coefficient N is less than the preset expected value, it is determined that no calibration is required, otherwise it is determined that calibration is required.

[0026] A second object of the present invention is to provide a global navigation satellite system recorded data laboratory playback calibration device, comprising:

[0027] The recording module is used to set up a full-band full-constellation reference receiver and a GNSS signal recording device for synchronous NMEA message recording;

[0028] The statistics module is used to perform constellation number distribution and power level statistics for the reference NMEA messages generated by the GNSS signal recording device and the NMEA messages of the full-band and full-constellation reference receiver in the playback environment;

[0029] The calibration module is used for determining a minimum approximation coefficient based on the number distribution and power level of the constellation, and calibrating the global navigation satellite system recorded data based on the minimum approximation coefficient.

[0030] The third object of the present invention is to provide an electronic device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute each step in the method of the aforementioned technical solution.

[0031] A fourth object of the present invention is to provide a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to enable a computer to execute each step in the method according to the aforementioned technical solution.

[0032] Different from the prior art, the laboratory playback calibration method for recorded data of a global navigation satellite system provided by the present invention obtains the calibration data required for the playback environment when the signal levels of the two scenes are as close as possible by objectively comparing the GNSS signal power levels reported by the NMEA messages of the reference receiver in the actual scene within the same time period with the NMEA messages of the same receiver in the playback scene; the maximum approximation degree is calculated by considering multiple factors including the distribution characteristics of C / No, maximum power, minimum power, average power and other correlation coefficients; the coefficient of the maximum approximation degree can be changed according to the different focus of different scenes; through the present invention, the laboratory playback restoration of recorded data can be achieved objectively and accurately, and the calibration data can be traced; the GNSS signal power level is as close to the desired recording scene as possible, and it is more possible for the laboratory to replace road testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention and / or additional aspects and advantages will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0034] Figure 1 The present invention provides a flowchart of a method for laboratory playback calibration of recorded data of a global navigation satellite system.

[0035] Figure 2 It is a schematic diagram of setting thresholds for star cluster quantity distribution statistics in a global navigation satellite system recorded data laboratory playback calibration method provided by the present invention.

[0036] Figure 3 The present invention provides a logic schematic diagram of a global navigation satellite system recorded data laboratory playback calibration method.

[0037] Figure 4 It is a structural schematic diagram of a global navigation satellite system recorded data laboratory playback calibration device provided by the present invention.

[0038] Figure 5 It is a structural schematic diagram of a non-temporary computer-readable storage medium provided by the present invention. DETAILED DESCRIPTION

[0039] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0040] like Figure 1 As shown, a global navigation satellite system recorded data laboratory playback calibration method provided by an embodiment of the present invention includes:

[0041] Set up a full-band full-constellation reference receiver and a GNSS signal recording device to synchronize NMEA message recording;

[0042] The distribution and power level of the constellation are counted for the reference NMEA messages generated by the GNSS signal recording device and the NMEA messages of the full-band and full-constellation reference receiver in the playback environment;

[0043] Based on the constellation population distribution and power level, the lowest approximation factor is determined, and the GNSS recorded data is calibrated based on the lowest approximation factor.

[0044] Among them, in the step of performing the distribution of the number of star clusters, the distribution statistics of the number of star clusters are simultaneously performed on the reference NMEA message and the NMEA message of the same reference receiver in the playback environment, and the number of star clusters is separated according to the star cluster frequency band, and the maximum power, minimum power, and average power of the carrier-to-noise ratio C / No of each star cluster frequency band are calculated at the same time.

[0045] Among them, in the step of determining the lowest approximation coefficient, the reference message is identified as File1, the calibrated environment message is identified as File2, the statistical distribution results of the different constellation frequency bands of the two NMEA files (DIST1, DIST 2, ..., DIST(n)), and the maximum power (MAX1, MAX2, ..., MAX(n)), the minimum power (MIN1, MIN 2, ..., MIN(n)) and the average power (AVG1, AVG 2, ..., AVG(n)) of the distribution are used as algorithm output parameters to calculate the approximation coefficient N.

[0046] Wherein, based on the maximum power, the minimum power and the average power, the distribution coefficient D, the minimum power coefficient S, the maximum power coefficient M, and the average power coefficient A are determined.

[0047] Among them, the distribution coefficient D, minimum power coefficient S, maximum power coefficient M, and average power coefficient A are expressed as follows:

[0048]

[0049]

[0050]

[0051]

[0052] Among them, the formula for the minimum approximation coefficient N is expressed as:

[0053] N=f1*D+f2*S+f3*M+f4*A

[0054] Among them, f1, f2, f3, and f4 are weight coefficients, which are modified according to the focus.

[0055] Among them, a preset expected value is set, and the lowest approximation coefficient N is compared with the preset expected value. If the lowest approximation coefficient N is less than the preset expected value, it is determined that no calibration is required, otherwise it is determined that calibration is required.

[0056] During the GNSS signal recording process, a full-band full-constellation reference receiver is required to perform NMEA message recording synchronously with the GNSS signal recording equipment. This recorded message serves as a reference for the power level of the GNSS signal recorded and played back in the laboratory. The goal of the calibration algorithm is to make the power level of the laboratory playback signal as close as possible from multiple angles to the GNSS signal power level fed back in the NMEA message recorded synchronously during the GNSS signal recording process.

[0057] The core of the algorithm includes two parts: segmented statistics of satellite C / No distribution and average power level. The calibration process adopts a closed-loop calibration method. The GNSS recording and playback data with the prerequisite of reference NMEA messages can be self-calibrated for different test environment deployments. If there is no change in the environment and equipment, it only needs to be calibrated once and saved. The calibration result is used as the calibration data dynamically loaded in the subsequent test process.

[0058] C / No quantity distribution statistics need to set the statistical threshold first, which can be set according to the actual calibration accuracy requirements. Figure 2 shown.

[0059] During the algorithm execution, the C / No distribution statistics are performed on the reference NMEA message and the NMEA message of the same reference receiver in the playback environment. The maximum power, minimum power, and average power of the C / No carrier-to-noise ratio of each constellation frequency band are calculated at the same time. (C / No represents the ratio of carrier power to noise power spectral density, in dBHz.) The calculation results are shown in Table 1:

[0060]

[0061] Table 1 Calculation results

[0062] The reference message is generally identified as File1, and the calibrated environment message is generally identified as File2. The statistical distribution results of the different constellation frequency bands of the two NMEA files (DIST1, DIST 2, ..., DIST(n)), as well as the maximum power (MAX1, MAX2, ..., MAX(n)), minimum power (MIN1, MIN 2, ..., MIN(n)) and average power (AVG1, AVG2, ..., AVG(n)) of the distribution are used as algorithm output parameters to calculate the approximation coefficient N. The process includes the calculation of the distribution coefficient D, minimum power coefficient S, maximum power coefficient M, and average power coefficient A.

[0063] The above algorithm is only the basic algorithm in the whole calibration process. The automatic calibration can adopt the following automatic calibration process to realize the automatic calibration of GNSS recorded data laboratory playback. Figure 3 The process is shown.

[0064] like Figure 4 As shown, the present invention also provides a global navigation satellite system recorded data laboratory playback calibration device, comprising:

[0065] The recording module 310 is used to set a full-band full-constellation reference receiver and a global navigation satellite system GNSS signal recording device to perform synchronous NMEA message recording;

[0066] A statistics module 320 is used to perform constellation quantity distribution and power level statistics for reference NMEA messages generated by a GNSS signal recording device and NMEA messages of a full-band full-constellation reference receiver in a playback environment;

[0067] The calibration module 330 is used to determine a minimum approximation coefficient based on the number distribution and power level of the constellation, and calibrate the global navigation satellite system recorded data based on the minimum approximation coefficient.

[0068] In order to implement the embodiment, the present invention also proposes an electronic device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute each step in the global navigation satellite system recorded data laboratory playback calibration method of the aforementioned technical solution.

[0069] like Figure 5As shown, the non-transitory computer-readable storage medium includes a memory 810 of instructions, an interface 830, and the instructions can be executed by a processor 820 for calibrating the laboratory playback of the global navigation satellite system recorded data to complete the method. Optionally, the storage medium can be a non-transitory computer-readable storage medium, for example, the non-transitory computer-readable storage medium can be a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc.

[0070] In order to implement the embodiment, the present invention further proposes a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the laboratory playback calibration of the recorded data of the global navigation satellite system as in the embodiment of the present invention.

[0071] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0072] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0073] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present invention belong.

[0074] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute the instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0075] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the described embodiment, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0076] A person skilled in the art may understand that all or part of the steps of implementing the method of the embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0077] In addition, each functional unit in each embodiment of the present invention may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0078] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present invention have been shown and described above, it can be understood that the embodiments are exemplary and cannot be construed as limiting the present invention. A person of ordinary skill in the art may change, modify, replace and modify the embodiments within the scope of the present invention.

Claims

1. A method for laboratory playback calibration of recorded data of a global navigation satellite system, characterized in that: include: Set up a full-band full-constellation reference receiver and a GNSS signal recording device to synchronize NMEA message recording; Perform constellation quantity distribution and power level statistics for the reference NMEA message generated by the GNSS signal recording device and the NMEA message of the full-band full-constellation reference receiver in the playback environment; In the step of performing the distribution of the number of star clusters, the distribution statistics of the number of star clusters are simultaneously performed on the reference NMEA message and the NMEA message of the same reference receiver in the playback environment, and the number of star clusters is separated according to the frequency band of the star clusters, and the maximum power, minimum power, and average power of the carrier-to-noise ratio C / No of each frequency band of the star cluster are calculated at the same time; Determining a minimum approximation coefficient based on the number distribution and power level of the constellation, and calibrating the global navigation satellite system recorded data based on the minimum approximation coefficient; In the step of determining the lowest approximation coefficient, the reference message is identified as File1, the calibrated environment message is identified as File2, and the statistical distribution results of the different constellation frequency bands of the two NMEA files (DIST1, DIST 2, ..., DIST(n)), as well as the maximum power (MAX1, MAX2, ..., MAX(n)), the minimum power (MIN1, MIN 2, ..., MIN(n)) and the average power (AVG1, AVG 2, ..., AVG(n)) of the distribution are used as algorithm output parameters to calculate the approximation coefficient N; The distribution coefficient D, minimum power coefficient S, maximum power coefficient M, and average power coefficient A are expressed as follows: The formula for the minimum approximation coefficient N is: N=f1*D+f2*S+f3*M+f4*A Among them, f1, f2, f3, f4 are weight coefficients; Wherein, n represents the number of statistical data in the reference NMEA message generated by the GNSS signal recording device and the NMEA message of the full-band full-constellation reference receiver in the playback environment.

2. The GNSS recorded data laboratory playback calibration method according to claim 1, characterized in that: A preset expected value is set, and the minimum approximation coefficient N is compared with the preset expected value. If the minimum approximation coefficient N is less than the preset expected value, it is determined that no calibration is required, otherwise it is determined that calibration is required.

3. A global navigation satellite system recorded data laboratory playback calibration device, characterized in that: include: The recording module is used to set up a full-band full-constellation reference receiver and a GNSS signal recording device for synchronous NMEA message recording; A statistics module, for performing constellation quantity distribution and power level statistics on the reference NMEA message generated by the GNSS signal recording device and the NMEA message of the full-band full-constellation reference receiver in the playback environment; To distribute the number of constellations, the reference NMEA message and the NMEA message of the same reference receiver in the playback environment are simultaneously used to perform distribution statistics of the number of constellations, separated by constellation frequency bands, and the maximum power, minimum power, and average power of the carrier-to-noise ratio C / No of each constellation frequency band are calculated at the same time; A calibration module, configured to determine a minimum approximation coefficient based on the number distribution and power level of the constellation, and calibrate the global navigation satellite system recorded data based on the minimum approximation coefficient; In the step of determining the lowest approximation coefficient, the reference message is identified as File1, the calibrated environment message is identified as File2, and the statistical distribution results of the different constellation frequency bands of the two NMEA files (DIST1, DIST 2, ..., DIST(n)), as well as the maximum power (MAX1, MAX2, ..., MAX(n)), the minimum power (MIN1, MIN 2, ..., MIN(n)) and the average power (AVG1, AVG 2, ..., AVG(n)) of the distribution are used as algorithm output parameters to calculate the approximation coefficient N; The distribution coefficient D, minimum power coefficient S, maximum power coefficient M, and average power coefficient A are expressed as follows: The formula for the minimum approximation coefficient N is: N=f1*D+f2*S+f3*M+f4*A Among them, f1, f2, f3, f4 are weight coefficients; Wherein, n represents the number of statistical data in the reference NMEA message generated by the GNSS signal recording device and the NMEA message of the full-band full-constellation reference receiver in the playback environment.

4. An electronic device comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can perform each step in the method described in any one of claims 1-2.

5. A non-transitory computer-readable storage medium storing computer instructions, wherein: The computer instructions are used to enable the computer to execute each step in the method according to any one of claims 1-2.

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