A method for evaluating unequal length load-to-noise ratio curve correlation

Abstract

The present application relates to a kind of not equal length carrier-to-noise ratio curve correlation evaluation method.The method includes: obtaining multiple groups of carrier-to-noise ratio curves of satellite signal, selecting any two groups of carrier-to-noise ratio curves to construct carrier-to-noise ratio correlation matrix and pitch angle correlation matrix.According to pitch angle correlation matrix, the sum of the absolute value of the difference of adjacent elements in pitch angle sequence is calculated, and the pitch angle change amplitude sequence is obtained.The time corresponding to the minimum value in pitch angle change amplitude sequence is taken as initial time, and the carrier-to-noise ratio of carrier-to-noise ratio correlation matrix is reorganized according to initial time, and the ordered carrier-to-noise ratio sequence to be evaluated is obtained.According to pitch angle change amplitude sequence, set correlation evaluation value, and according to this, align the ordered carrier-to-noise ratio sequence to be evaluated, and carry out feature evaluation with historical carrier-to-noise ratio sequence, and obtain feature comparison result.Using this method can detect satellite signal carrier-to-noise ratio anomaly in time and effectively, improve detection timeliness.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of satellite signal monitoring, in particular to a method for evaluating the correlation of unequal length carrier-to-noise ratio curves. BACKGROUND

[0002] When monitoring satellite signals, the change of the signal carrier-to-noise ratio needs to be monitored. When the relative position relationship between the satellite and the monitoring station is consistent, the change of the satellite state is determined by comparing the change of the carrier-to-noise ratio characteristics. However, the transit time of the satellite is not exactly consistent each time, and the data received by the station may be lost. Therefore, the characteristics of the unequal length carrier-to-noise ratio array need to be compared in time sequence, and after aligning the data, the result of the characteristic comparison is obtained to evaluate the correlation between the curves. SUMMARY

[0003] Therefore, it is necessary to provide a method for evaluating the correlation of unequal length carrier-to-noise ratio curves to improve the timeliness of satellite signal carrier-to-noise ratio anomaly detection.

[0004] A method for evaluating the correlation of unequal length carrier-to-noise ratio curves, the method comprising:

[0005] Obtaining multiple groups of carrier-to-noise ratio curves of satellite signals, and selecting any two groups of carrier-to-noise ratio curves to construct a carrier-to-noise ratio correlation matrix and an elevation angle correlation matrix.

[0006] According to the elevation angle correlation matrix, the sum of the absolute values of the differences between adjacent elements in the elevation angle sequence is calculated to obtain an elevation angle change amplitude sequence.

[0007] Taking the time corresponding to the minimum value in the elevation angle change amplitude sequence as the initial time, the carrier-to-noise ratio of the carrier-to-noise ratio correlation matrix is reorganized according to the initial time to obtain an ordered carrier-to-noise ratio sequence to be evaluated.

[0008] According to the elevation angle change amplitude sequence, a correlation evaluation value is set, and after aligning the ordered carrier-to-noise ratio sequence to be evaluated according to the correlation evaluation value, the characteristic evaluation is performed on the historical carrier-to-noise ratio sequence to obtain a characteristic comparison result.

[0009] The above-mentioned unequal-length carrier-to-noise ratio curve correlation evaluation method first acquires multiple groups of carrier-to-noise ratio curves and constructs a carrier-to-noise ratio and pitch angle correlation matrix, calculates the sum of absolute values of differences between adjacent elements in the pitch angle matrix to obtain a change amplitude sequence, this step breaks the sequence disorder caused by unequal transit time and packet loss, and excavates potential time correlation through the pitch angle change rule. Then, the minimum value of the amplitude sequence is selected as the initial time to reorganize the carrier-to-noise ratio, the disordered and packet loss-affected carrier-to-noise ratio data is reorganized into an ordered sequence based on the pitch angle logic, the influence of transit time difference is overcome, and the carrier-to-noise ratio sequence is returned to a comparable time reference. Finally, the ordered carrier-to-noise ratio sequence to be evaluated is evaluated according to the pitch angle change amplitude sequence, the ordered and stable sequence reorganized in the early stage is used to accurately capture the carrier-to-noise ratio characteristics, the characteristics are prevented from being misjudged due to data packet loss and unequal time, and the abnormality is quickly located. From data processing, sequence reorganization to characteristic evaluation, the steps are closely linked, timely and effective detection of satellite signal carrier-to-noise ratio anomaly is realized, and the detection timeliness is improved. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 FIG. 1 is a flowchart of an unequal-length carrier-to-noise ratio curve correlation evaluation method according to an embodiment;

[0011] Figure 2 FIG. 2 is a flowchart of a carrier-to-noise ratio curve correlation evaluation step according to an embodiment. DETAILED DESCRIPTION

[0012] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0013] In one embodiment, as shown in FIG. 1, an unequal-length carrier-to-noise ratio curve correlation evaluation method is provided, including the following steps: Figure 1

[0014] Step 102, multiple groups of carrier-to-noise ratio curves of satellite signals are acquired, and a carrier-to-noise ratio correlation matrix and a pitch angle correlation matrix are constructed by selecting any two groups of carrier-to-noise ratio curves.

[0015] Step 104, the sum of absolute values of differences between adjacent elements in the pitch angle sequence is calculated according to the pitch angle correlation matrix to obtain a pitch angle change amplitude sequence.

[0016] Step 106, the time corresponding to the minimum value in the pitch angle change amplitude sequence is taken as the initial time, and the carrier-to-noise ratio of the carrier-to-noise ratio correlation matrix is reorganized according to the initial time to obtain an ordered carrier-to-noise ratio sequence to be evaluated.

[0017] ​Step 108, set the correlation evaluation value according to the pitch angle change amplitude sequence, align the ordered carrier-to-noise ratio sequence to be evaluated according to the correlation evaluation value, and perform feature evaluation on the historical carrier-to-noise ratio sequence to obtain a feature comparison result.

[0018] In the above unequal length carrier-to-noise ratio curve correlation evaluation method, first, a plurality of groups of carrier-to-noise ratio curves are obtained and a carrier-to-noise ratio and pitch angle correlation matrix is constructed, the sum of the absolute values of the differences between adjacent elements is calculated using the pitch angle matrix to obtain a change amplitude sequence, this step breaks the sequence disorder caused by different transit times and packet loss, and potential time correlation is mined through the pitch angle change rule. Next, the minimum value of the amplitude sequence is selected as the initial time to reorganize the carrier-to-noise ratio, the unordered and packet loss-affected carrier-to-noise ratio data is reorganized into an ordered sequence based on the pitch angle logic, the influence of the transit time difference is overcome, and the carrier-to-noise ratio sequence is returned to a comparable time reference. Finally, the ordered carrier-to-noise ratio sequence to be evaluated is evaluated according to the pitch angle change amplitude sequence, the ordered and stable sequence reorganized in the early stage is used to accurately capture the carrier-to-noise ratio features, feature misjudgment caused by data packet loss and unequal time is avoided, and the abnormality is quickly located. From data processing, sequence reorganization to feature evaluation, it is closely linked to realize timely and effective detection of satellite signal carrier-to-noise ratio anomaly and improve the detection timeliness.

[0019] In one embodiment, as shown in Figure 2 , a carrier-to-noise ratio curve correlation evaluation step is provided, and the specific content is as follows:

[0020] Step S1, obtain the corresponding time sequence based on the satellite pitch angle change: assuming that there are two groups of carrier-to-noise ratio curves, which can be represented as:

[0021] ; ;

[0022] The satellite pitch angle corresponding to each time can be represented as , , where , respectively represent the elevation angle and the azimuth angle. Assuming , then , is constructed.

[0023] Step S2, obtain the corresponding time sequence based on the satellite pitch angle change: calculate .

[0024] Step S3, obtain the corresponding time sequence based on the satellite pitch angle change: obtain the corresponding to the minimum value in the sequence .

[0025] Step S4, obtaining corresponding time sequence based on satellite elevation angle change: sequence order can be expressed as .

[0026] Step S5, aligning carrier-to-noise ratio curve: arranging the order obtained in the previous step, the .

[0027] Step S6, comparing carrier-to-noise ratio curve characteristics: calculating , and the average of the minimum value in the sequence as the evaluation between the curve correlations. When exceeds the threshold, it is judged that the carrier-to-noise ratio curve characteristics have changed.

[0028] In one embodiment, the change of the satellite signal elevation angle in a period of time is obtained, and a plurality of carrier-to-noise ratio curves are drawn, and any two carrier-to-noise ratio curves corresponding to different time periods are selected:

[0029] ;

[0030] ;

[0031] ;

[0032] ;

[0033] wherein, is the first carrier-to-noise ratio sequence, is the second carrier-to-noise ratio sequence, is the carrier-to-noise ratio at the moment in the first sequence, is the carrier-to-noise ratio at the moment in the second sequence, is the elevation angle sequence corresponding to the first carrier-to-noise ratio sequence, is the elevation angle sequence corresponding to the second carrier-to-noise ratio sequence, is the total number of the first carrier-to-noise ratio sequence, is the total number of the second carrier-to-noise ratio sequence. The first carrier-to-noise ratio sequence and the second carrier-to-noise ratio sequence construct a carrier-to-noise ratio correlation matrix:

[0034] ;

[0035] wherein, is the carrier-to-noise ratio correlation matrix. The elevation angle sequence corresponding to the first carrier-to-noise ratio sequence and the elevation angle sequence corresponding to the second carrier-to-noise ratio sequence construct an elevation angle correlation matrix:

[0036] ;

[0037] wherein, is the pitch angle related matrix.

[0038] In one of the embodiments, the sum of absolute values of differences between corresponding adjacent elements in the pitch angle related matrix in a preset time period is calculated to obtain a pitch angle change amplitude sequence:

[0039] ;

[0040] wherein, is the pitch angle change amplitude sequence corresponding to the time period k, is the elevation angle and azimuth angle at the i th moment, is the elevation angle and azimuth angle at the i th moment. In one of the embodiments, the moment corresponding to the minimum value in the pitch angle change amplitude sequence is taken as the initial time, and the carrier-to-noise ratio corresponding to each moment in the carrier-to-noise ratio related matrix is reorganized in ascending order of time according to the initial time to obtain an ordered carrier-to-noise ratio sequence to be evaluated:

[0041] ;

[0042] ;

[0043] wherein, is the initial time,

[0044] is the time interval from the initial time, is the ordered carrier-to-noise ratio sequence to be evaluated. In one of the embodiments, after aligning the ordered carrier-to-noise ratio sequence to be evaluated according to the correlation evaluation value, the ordered carrier-to-noise ratio sequence to be evaluated and the second group of carrier-to-noise ratio sequences are subjected to feature evaluation, and when the ordered carrier-to-noise ratio sequence to be evaluated reordered corresponds to the data of the epochs of the second group of carrier-to-noise ratio sequences

[0045] , a difference sequence is obtained by comparison:

[0046] ;

[0047] The number of quantities greater than the threshold value in the difference sequence is obtained, and the number of quantities is counted. Assuming that there are quantities exceeding the threshold value, when is greater than a preset length of time, it is considered that the carrier-to-noise ratio curve feature has changed, and otherwise it is considered that the carrier-to-noise ratio curve feature has not changed.

[0048] It should be understood that, although Figures 1-2 ​​The steps in the flowcharts of the above embodiments are shown in sequence according to the arrows, but the steps are not necessarily executed in the order shown by the arrows. Unless otherwise specified herein, the steps are not necessarily executed in strict sequence, and the steps can be executed in other sequences. Moreover, Figures 1-2 At least part of the steps in the flowcharts of the above embodiments can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of the sub-steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or sub-steps or stages of other steps.

[0049] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing related hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when executed, can include the processes of the above-mentioned embodiments of the methods. Any reference to memory, storage, database or other medium used in the embodiments provided by the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0050] The technical features of the above embodiments can be combined in any way. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described, but as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0051] The above-described embodiments only express several implementation ways of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation to the scope of the application. It should be pointed out that, for ordinary skilled in the art, without departing from the concept of the present application, various modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method for evaluating the correlation of unequal-length carrier-to-noise ratio curves, characterized in that, The method includes: Multiple sets of carrier-to-noise ratio (CNR) curves of satellite signals are obtained, and any two sets of CNR curves are selected to construct a CNR correlation matrix and an elevation angle correlation matrix. Obtain the elevation angle change of the satellite signal over a period of time, plot multiple sets of carrier-to-noise ratio (CNR) curves, and select any two sets of CNR curves corresponding to different time periods: in, This is the first set of carrier-to-noise ratio sequences. This is the second set of carrier-to-noise ratio sequences. The first in the first group Carrier-to-noise ratio at any given moment The second set of carrier-to-noise ratio sequences Carrier-to-noise ratio at any given moment This is the elevation angle sequence corresponding to the first set of carrier-to-noise ratio sequences. This is the elevation angle sequence corresponding to the second set of carrier-to-noise ratio sequences. The total number of carrier-to-noise ratios in the first group. This represents the total number of carrier-to-noise ratios in the second group; The pitch angle change amplitude sequence is obtained by calculating the sum of the absolute values ​​of the differences between adjacent elements in the pitch angle sequence based on the pitch angle correlation matrix. The time corresponding to the minimum value in the pitch angle change amplitude sequence is taken as the initial time. The carrier noise ratio of the carrier noise ratio correlation matrix is ​​reorganized according to the initial time to obtain the ordered carrier noise ratio sequence to be evaluated. Based on the pitch angle change amplitude sequence, a correlation evaluation value is set. After aligning the ordered carrier-to-noise ratio sequence to be evaluated based on the correlation evaluation value, feature evaluation is performed with the historical carrier-to-noise ratio sequence to obtain the feature comparison result. After aligning the ordered carrier-to-noise ratio (CNR) sequence to be evaluated according to the correlation evaluation value, feature evaluation is performed on the ordered CNR sequence to be evaluated and the second set of CNR sequences. When the reordered ordered CNR sequence to be evaluated... With the second set of carrier-to-noise ratio sequences By comparing data from corresponding epochs, a difference sequence is obtained: Obtain the difference sequence The quantities that exceed the threshold are counted, and the number of such quantities is recorded. Assume there are... If any value exceeds the threshold, then when If the duration exceeds the preset time, it is considered that the characteristics of the carrier-to-noise ratio curve have changed; otherwise, they have not.

2. The method according to claim 1, characterized in that, Multiple sets of carrier-to-noise ratio (CNR) curves of satellite signals are acquired, and any two sets of CNR curves are selected to construct a CNR correlation matrix and an elevation angle correlation matrix, including: The first set of carrier-to-noise ratio (CNR) sequences and the second set of CNR sequences are used to construct a CNR correlation matrix: in, The carrier-to-noise ratio correlation matrix; Construct an elevation angle correlation matrix using the elevation angle sequences corresponding to the first set of carrier-to-noise ratio sequences and the second set of carrier-to-noise ratio sequences: in, This is the pitch angle correlation matrix.

3. The method according to claim 2, characterized in that, The pitch angle change amplitude sequence is obtained by summing the absolute values ​​of the differences between adjacent elements in the pitch angle sequence based on the pitch angle correlation matrix, including: Based on the pitch angle correlation matrix, the sum of the absolute values ​​of the differences between adjacent elements within a preset time period is calculated to obtain the pitch angle change amplitude sequence: in, This is a sequence of pitch angle variation amplitudes corresponding to time period k. For the first The elevation and azimuth angles at each moment. For the first The elevation and azimuth angles at each moment.

4. The method according to claim 3, characterized in that, Taking the moment corresponding to the minimum value in the pitch angle change amplitude sequence as the initial time, the carrier-to-noise ratio (CNR) of the carrier-to-noise ratio correlation matrix is ​​reconstructed based on the initial time to obtain the ordered CNR sequence to be evaluated, including: The time corresponding to the minimum value in the pitch angle change amplitude sequence is taken as the initial time. Based on the initial time, the carrier-to-noise ratio (CNR) of each time point in the carrier-to-noise ratio (CNR) correlation matrix is ​​reorganized in ascending order of time, resulting in an ordered CNR sequence to be evaluated. in, The initial time, The time interval from the initial time, The sequence is an ordered carrier-to-noise ratio sequence to be evaluated.

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