JP2019078699A - GNSS analyzer, GNSS analysis system, GNSS analysis method, and GNSS analysis program - Google Patents

Abstract

To provide a GNSS analyzer with which it is possible to sufficiently suppress the effect of diffraction and multipath, and which is usable for versatile purposes.SOLUTION: A GNSS analyzer 25 comprises a determination unit 41, a first effective period determination unit 42, a second effective period determination unit 43, and a baseline analysis unit 44. The determination unit 41 creates a determination result of whether a carrier for determination and a carrier for analysis received by GNSS receivers 24, 34 are valid or not, or acquires the determination result. The first effective period determination unit 42 determines on the basis of the determination result of the carrier for determination, a first effective period that is a period for which the determination result is estimated to be valid in a sidereal daily cycle. The second effective period determination unit 43 excludes an interval of the first effective period from a start time to after a first period and excludes an interval of the first effective period from an end time to before a second period, and thereby determines a second effective period. The baseline analysis unit 44 analyzes a baseline using the carrier for analysis that is received in the second effective period and the determination result of which is effective.SELECTED DRAWING: Figure 1

Description

  The present invention relates mainly to a GNSS analyzer. In particular, the present invention relates to a configuration for performing baseline analysis by removing errors caused by poor visibility in the sky, multipath, and the like.

  2. Description of the Related Art A displacement monitoring system is conventionally known that monitors the displacement of a monitoring station relative to a reference station using a GNSS (Global Navigation Satellite System). Each of the observation station and the reference station is provided with a GNSS antenna, receives a GNSS signal from a GNSS satellite, and transmits observation data to the arithmetic unit. The arithmetic unit performs baseline analysis based on observation data transmitted from the observation station and observation data transmitted from the reference station to determine the relative position of the observation station with respect to the reference station. Based on the change in relative position, the displacement of the observation station relative to the reference station can be monitored.

  Here, in GNSS, since positioning is performed by receiving a weak GNSS signal from a satellite, the accuracy of baseline analysis may decrease or baseline analysis itself may not be performed depending on the reception condition of GNSS signal or the like. Sometimes. Specifically, a phenomenon in which the GNSS signal is blocked by an obstacle, a phenomenon in which the GNSS signal is received after reflection from the obstacle (multipath) occurs, a phenomenon in which the GNSS signal diffracted by the obstacle is received There is something to do. Patent documents 1 and 2 and non-patent documents 1 and 2 disclose techniques for reducing the influence of obstacles on baseline analysis.

  Patent Document 1 sets the elevation angle and azimuth angle of a GNSS satellite that has successfully received a GNSS signal as a range in which the field of view is open as viewed from the reception point. Disclosed are techniques for preventing processing. Patent Document 2 discloses a technology for judging the state of a GNSS satellite based on the carrier-to-noise ratio (CN ratio) of the GNSS signal and shielding the GNSS signal from the GNSS satellite judged to be shielded.

  Non-Patent Document 1 creates an obstacle mask by measuring the position of an obstacle (specifically, the elevation angle and azimuth angle at which the obstacle is present) using a fisheye image in the air at the receiving point. The GNSS signal received from the mask is not used for baseline analysis. Non-Patent Document 2 is a value (DSS) obtained by subtracting the signal strength obtained at the reference station from the signal strength obtained at the mobile station for the carrier obtained from the same satellite, and the carrier phase change amount at the reference station and the mobile station. Disclosed is a method of detecting satellites affected by multipath using difference (DDPC).

Unexamined-Japanese-Patent No. 9-297170 Patent 5559016 gazette

"Evaluation of Multipath Reduction Method by Sky Vision Information at Stationary Point", [online], [April 15, 2017 search], Internet <URL: http://www.denshi.e.kaiyodai.ac.jp/jp /assets/files/pdf/content/20160428_IPNTJ_tokura.pdf> Takahiro Ikeda, "Verification of application effect of multipath detection method using signal strength and carrier phase change amount in satellite positioning", Monthly "surveying", Japan Surveying Association, January 2017, p. 12-15

  Here, immediately after the GNSS signal can not be received immediately after reception, a situation occurs in which signal strength of the carrier wave is high but diffraction and multipath of the GNSS signal are likely to occur. Therefore, the methods of Patent Documents 1 and 2 can not sufficiently suppress the influence of diffraction and multipath because judgment is performed based on the presence / absence of reception of the GNSS signal and the CN ratio, respectively. In addition, since the method of Non-Patent Document 1 uses an image obtained by a camera, basically the effects of diffraction and multipath can not be sufficiently suppressed, as in Patent Document 1 and the like. Further, the method of Non-Patent Document 2 is based on the premise that the conditions of the obstacle around the reference point and the observation point are similar, so there is room for improvement in terms of versatility.

  The present invention has been made in view of the above circumstances, and its main object is to provide a highly versatile GNSS analyzer while sufficiently suppressing the effects of diffraction and multipath.

Means and effect for solving the problem

  The problem to be solved by the present invention is as described above, and next, means for solving the problem and its effect will be described.

  According to an aspect of the present invention, a GNSS analysis device having the following configuration is provided. That is, this GNSS analysis device includes a determination unit, a first effective period determination unit, a second effective period determination unit, and a baseline analysis unit. The determination unit creates a determination result of valid or invalid of the carrier wave including the determination carrier wave and the analysis carrier wave received by the GNSS receiver, or obtains the determination result. The first effective period determination unit determines a first effective period which is a period in which the determination result is estimated to be effective in the stellar date cycle, based on the determination result of the determination carrier. The second valid period determining unit excludes the start of the first valid period to the end of the first period, and further excludes the end of the first valid period to the second period before the second valid period. Determine the period. The base line analysis unit performs base line analysis using the analysis carrier wave received during the second valid period and whose determination result is valid. Further, according to another aspect of the present invention, there are provided a GNSS analysis method and a GNSS analysis program for performing the above-mentioned processing.

  As a result, baseline analysis is performed using carriers received in the second valid period excluding the start and end times of the first valid period, and therefore, the influence of diffraction and multipath can be suppressed. In addition, since the present technology can be applied even if the conditions of the obstacles of the reference station and the observation station are not the same, the versatility is high.

The block diagram showing the functional composition of the GNSS analysis system concerning one embodiment of the present invention. The figure which shows the schematic structure of a GNSS analysis system. The flowchart which shows the processing which the GNSS analysis device does. The figure explaining the process which determines whether the carrier wave for analysis is used for baseline analysis. The figure which shows the determination result of the carrier wave for determination, a 1st effective period, and a 2nd effective period. The figure which shows the determination result of the carrier for analysis, the 2nd effective period for determining use / non-use, and the determination result of use / non-use. The figure which shows the SN ratio of a carrier wave, and the determination result based on SN ratio.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a functional configuration of a GNSS analysis system 1 according to an embodiment of the present invention. FIG. 2 is a diagram showing a schematic configuration of the GNSS analysis system 1. As GNSS, any of GPS, QZSS, GLONASS, GALILEO, etc. can be used.

  As shown in FIGS. 1 and 2, the GNSS analysis system 1 includes a reference station measurement device 2 disposed in a reference station and an observation station measurement device 3 disposed in an observation station. Although only one observation station is illustrated in FIGS. 1 and 2, a plurality of observation stations may exist.

  For example, in the case of monitoring ground displacement at a site where there is a risk of landslide using this GNSS analysis system 1, the observation station measurement device 3 is installed at a location (observation station) where landslide is likely to occur. Further, the reference station measurement device 2 is installed at a fixed point (reference station) which is not affected by landslide. And the displacement of the ground can be detected by monitoring the position of the observation station with respect to the reference station and its change in position.

  As shown in FIG. 2, in the reference station measurement device 2, the GNSS antenna 20, the solar cell 21, and the housing 22 are integrally attached to the pole 23. Similarly, in the observation station measurement device 3, the GNSS antenna 30, the solar cell 31, and the housing 32 are integrally attached to the pole 33. As described above, since the reference station measurement device 2 and the observation station measurement device 3 are integrally and compactly configured with the pole, they can be easily carried. Also, the pole can be easily installed on the site simply by standing on the ground.

  Inside the housing 22 of the reference station measurement device 2, a GNSS receiver 24 and a GNSS analysis device 25 are provided.

  The GNSS receiver 24 receives radio waves (carrier waves) from GNSS satellites via the GNSS antenna 20. The GNSS receiver 24 outputs a signal based on the radio wave to the GNSS analyzer 25. The GNSS receiver 24 also determines the validity / invalidity of the carrier based on the signal strength of the carrier received from the GNSS satellite, the lock state of the synchronization circuit, the SN ratio, etc., and sends this determination result to the GNSS analyzer 25. Output. In this embodiment, the carrier wave received for baseline analysis is referred to as a carrier wave for analysis, and the carrier wave for determining whether or not the carrier wave for analysis is used for baseline analysis is referred to as a carrier wave for determination. Further, in the following description, the term carrier is treated as a term including an analysis carrier and a determination carrier. Further, the determination carrier and the analysis carrier are names used for convenience of explanation, and there is a possibility that a carrier treated as a determination carrier in one process may be treated as an analysis carrier in another process.

  The GNSS analysis device 25 includes an arithmetic device including a CPU, a ROM, a RAM, and the like, and an electronic circuit in which electronic components such as a digital filter are disposed. In the GNSS analysis device 25, the CPU reads the program stored in the ROM into the RAM and executes the program, or operates the digital filter or the like on the electronic circuit to determine the determination unit 41, the first effective period determination unit 42, and the second The functions as the valid period determination unit 43 and the baseline analysis unit 44 can be exhibited. Furthermore, a program for causing a computer such as the GNSS analysis device 25 to function as the baseline analysis unit 44 from the determination unit 41 is a GNSS analysis program. Specific processes of the determination unit 41 to the baseline analysis unit 44 will be described later. Note that at least one of electronic components such as a digital filter provided in the GNSS analysis device 25 can also be realized by software.

  A GNSS receiver 34 and a processing device 35 are provided in the housing 32 of the observation station measurement device 3.

  The GNSS receiver 34 receives radio waves (carrier waves) from GNSS satellites via the GNSS antenna 30. The GNSS receiver 34 outputs a signal based on this radio wave to the processing device 35. Further, the GNSS receiver 34 determines the validity / invalidity of the carrier wave based on the signal strength of the carrier wave received from the GNSS satellite, the lock state of the synchronization circuit, the SN ratio, etc., and outputs this judgment result to the processing unit 35. Do.

  The processing device 35 wirelessly transmits the determination result of the validity / invalidity of the signal and the carrier wave received from the GNSS receiver 34 to the GNSS analysis device 25. The processing device 35 may transmit to the GNSS analysis device 25 not by wireless but by wire.

  Next, the process of calculating the relative displacement of the observation station with respect to the reference station using the GNSS analysis system 1 will be described with reference to FIGS. 3 and 4. FIG. 3 is a flowchart showing the process performed by the GNSS analyzer 25. FIG. 4 is a diagram for explaining the process of deciding whether to use the analysis carrier wave for baseline analysis.

  First, the GNSS analysis device 25 acquires data of the reference station from the GNSS receiver 24 and acquires data of the observation station from the processing device 35 (S101). The data acquired in step S101 includes not only the carrier wave but also the determination result indicating the validity / invalidity of the carrier wave. As described above, in the present embodiment, the GNSS analysis device 25 (determination unit 41) acquires the determination result determined and output by the GNSS receiver 24 and the GNSS receiver 34. Also, the GNSS receiver 24 and the GNSS receiver 34 determine and output valid / invalid carrier waves at predetermined time intervals.

  Next, the GNSS analysis device 25 (the first valid period determination unit 42 and the second valid period determination unit 43) determines each of the analysis carrier wave acquired by the reference station and the analysis carrier wave acquired by the observation station. A process of determining whether to use for baseline analysis or not for baseline analysis is performed (S102). In the following description, the process of step S102 is referred to as use / nonuse determination process.

  In the use / nonuse determination process, the use / nonuse of the analysis carrier of the reference station is determined using the determination result of the determination carrier obtained by the reference station, and the determination result of the determination carrier acquired by the observation station. Is used to determine whether to use the analysis carrier of the observation station. Since the process performed on the carrier wave of the reference station and the process performed on the carrier wave of the observation station are the same, the process performed on the carrier wave of the reference station will be described below.

  Hereinafter, the use / nonuse determination process will be described with reference to FIG. In the use / nonuse determination process, a first effective period determination process, a second effective period determination process, and a comparison determination process are performed.

  The first validity period determination process is performed by the first validity period determination unit 42. The first validity period determination process is based on the determination result of the determination carrier at least one stellar day (ie, the determination result of at least one carrier of one stellar day, two stellar days,...) This is a process of determining a first effective period, which is a period during which the determination carrier is estimated to be effective. In the present embodiment, the first validity period determination process is performed using the determination results of the determination carrier waves of one stellar day and two stellar days before. In the first effective period determination process, a star date filter process, a forward time series filter process, and a reverse time series filter process are performed.

  The stellar day filter process is a process using a low pass filter such as an infinite impulse response (IIR) filter and a memory for storage and delay. By performing the stellar day filtering process, the determination result of the validity / invalidity of the determination carrier wave acquired one or two stellar days before is output.

  In the forward time series filtering process, a process of excluding a period in which the determination result of the determination carrier wave is invalid on at least one of the determination result of one stellar day and the determination result of the two stellar days from the first effective period. Specifically, in the forward time series filtering process, data output by the stellar day filtering process is processed. Forward time series filtering is a process using a low pass filter such as an infinite impulse response (IIR) filter and a memory for storage and delay. By performing forward time series filter processing, the judgment result of the judgment carrier one staring day ago and the judgment result of the judgment carrier two staring days ago are respectively outputted, and the time series is ordered (the order of time series Can be compared in the order from the past to the present). In this comparison, when the determination carrier wave is invalid according to at least one of the determination results, the output determination result is processed so as to be invalid. That is, a period in which the determination carrier wave is invalidated even once in the determination carrier wave of the range to be determined is excluded from the first valid period. In other words, the period in which all the determination carriers are valid in the stellar day cycle is not excluded as the first valid period. Note that, by performing forward time series filter processing, a delay occurs.

  The backward time series filtering process is substantially the same process as the above-described forward time series filtering process, but the order of comparing the determination results is different. Specifically, in reverse time series filtering, the judgment result of the judgment carrier one staring day ago and the judgment result of the judgment carrier two star days ago are in the reverse order of the time series (from the present to the past) In the order of Thereby, the direction of the delay is also opposite to that of the forward time series filtering. Therefore, the delay can be eliminated by performing both the forward time series filtering process and the backward time series filtering process.

  The stabilization process excludes, from the first valid period, a period during which the determination result of the determination carrier wave is not valid for a predetermined period. In other words, in the stabilization process, the first valid period is included only when the determination result of the determination carrier wave continues to be valid for a predetermined period. Specifically, the stabilization processing acquires the determination result for a predetermined period toward the past and the future with respect to the determination result of one stellar day, and if at least one invalid result is included in the acquired determination result , That point is excluded from the first validity period. By performing the stabilization process, it is possible to temporarily exclude the portion in which the determination carrier wave is valid from the first valid period.

  The period not excluded from the first effective period in the above process corresponds to the first effective period. In the first valid period determination process, a period in which the analysis carrier is highly likely to be valid is extracted based on the determination result of the determination carrier. Here, in the case of fixed point observation such as landslide as in the present embodiment, it is assumed that the position of the obstacle around does not change so much, so the judgment result of the judgment carrier is also the same at each stellar day. There is a high possibility that the judgment result will be. Therefore, by performing time-series filter processing, the tendency can be output as a numerical value. Furthermore, by performing the stabilization process, it is possible to remove the period in which the carrier wave suddenly becomes effective due to some cause, so the period with higher reliability of data can be made the first effective period.

  The GNSS analysis device 25 performs a first validity period determination process every one or more stellar days. Therefore, for example, even if the situation of surrounding obstacles changes, such as heavy trees and logging, construction and dismantling of buildings, etc., the period for which the analysis carrier wave becomes invalid or is likely to become invalid due to the influence of obstacles The first effective period avoided can be determined.

  The second validity period determination process is performed by the second validity period determination unit 43. The second effective period determination process is performed on the first effective period. The second effective period determination process excludes the start of the first effective period to the end of the first period and further excludes the end of the first effective period to the end of the second period to obtain the second effective period. Is a process of determining Here, the determination of the validity / invalidity of the determination carrier is highly likely to be determined by the signal strength of the determination carrier, the lock state of the synchronization circuit, the SN ratio, and the like. However, even when radio waves from GNSS satellites are diffracted or multipaths occur, the signal strength of the determination carrier may be high or the SN ratio may be good, so the result of the determination of the carrier can be reliably trusted. Not necessarily. In addition, when the radio wave from the GNSS satellite is diffracted or multipath occurs, the carrier synchronization circuit is often maintained since the phase of the carrier wave changes slowly. For this reason, since the determination result of the carrier wave is not invalidated, a slowly varying error occurs in the baseline analysis result. Such diffraction and multipath often appear before and after the period in which the carrier synchronization state is continued. In consideration of the above, in the present embodiment, the second effective period with higher reliability is determined by excluding the beginning and end of the first effective period in which diffraction and multipath are likely to occur.

  The lengths of the first period and the second period excluded from the first effective period may be the same or different. Moreover, in the present embodiment, as described later, the first period and the second period may change depending on the situation, but the same value may be used continuously.

  FIG. 5 is a diagram showing a determination result of two stellar days before, a determination result of one stellar day before, a first effective period, and a second effective period in order from the top. In addition, each data is arranged up and down so that the timing in each staring day may be equal. As described above, the determination result of the determination carrier is substantially the same between one stellar day and two stellar days. In addition, portions that are valid one sterility day but are invalid two sterility days are excluded from the first valid period by time series filtering. Furthermore, the portion where the validity / invalidity frequently changes between one and two stellar days (that is, the portion where the validity is discontinuous) is excluded from the first validity period by the stabilization process. Further, in the second valid period, the first period and the second period described above are excluded from the first valid period.

  The comparison determination process is a process of comparing the second valid period and the determination result of the analysis carrier wave. FIG. 6 is a diagram showing the determination result of the analysis carrier, the second valid period, and the determination result of use / nonuse in order from the top. In the comparison determination process, when the determination result of the analysis carrier wave is valid and is included in the second validity period, as shown in FIG. 6, it is determined to use as a carrier wave used for baseline analysis. . When the determination result of the analysis carrier wave is invalid or when the time when the analysis carrier wave is received is not included in the second valid period, it is determined not to use as the analysis carrier wave used for the baseline analysis.

  Next, the GNSS analysis device 25 (baseline analysis unit 44) performs baseline analysis using the analysis carrier determined to be used for baseline analysis in step S102 (specifically, using the phase of the analysis carrier) (S103). ). In the GNSS analysis system 1 of this embodiment, an interference positioning method (specifically, static analysis, real-time kinematic analysis, etc.) is adopted as a method of obtaining a base line vector of the observation station. Although this interference positioning method is known, detailed description will be omitted, but it is a method of obtaining a baseline vector based on the phase difference of the analysis carrier of GNSS radio waves received by the reference station measurement device 2 and the observation station measurement device 3. . Then, the GNSS analysis device 25 calculates the relative displacement of the observation station with respect to the reference station based on the baseline vector (S104).

  Next, the GNSS analysis device 25 calculates error information (S105). The error information is information on an error included in the calculated relative displacement. For example, when diffraction of radio waves from GNSS satellites and multipath occur, the result of baseline analysis changes significantly, so it can be determined that an error has occurred. Furthermore, since the large change is returned to the original state by the elimination of the diffraction, the multipath, and the like after that, it can be determined more surely that the error has occurred.

  The GNSS analysis device 25 calculates a first period and a second period for further reducing the error based on the calculated error information (S106). There are various methods of calculating the first period and the second period. For example, baseline analysis is performed by lengthening or shortening the first period and the second period, and the state of the error is confirmed. Then, the first period and the second period when the error is most reduced are stored as values to be used in the next baseline analysis. As a result, even if the situation where diffraction and multi-pass or the like occur changes due to a change in the situation of the surrounding obstacle, it is possible to calculate the optimal first period and second period following it, so diffraction And multi-path can be suppressed.

  Next, modifications of the above embodiment will be described. FIG. 7 is a diagram showing the SN ratio of the carrier and the determination result based on the SN ratio. In the description of this modification, the same or similar members as or to those of the above-described embodiment may be denoted by the same reference numerals as those of the embodiment and the description thereof may be omitted.

  In the above embodiment, the GNSS analysis device 25 (determination unit 41) is configured to obtain the determination results of the GNSS receiver 24 and the GNSS receiver 34. Instead of this, in the present modification, the GNSS analysis device 25 (determination unit 41) performs this determination. Specifically, for the determination carrier or analysis carrier received from the GNSS receiver 24 and the GNSS receiver 34, a portion where the SN ratio exceeds the threshold is determined as valid, and a portion where the SN ratio is less than the threshold is invalidated. judge. The method of using the determination carrier wave or the analysis carrier wave is the same as that of the above embodiment.

  As described above, the GNSS analysis device 25 according to the embodiment includes the determination unit 41, the first valid period determination unit 42, the second valid period determination unit 43, and the baseline analysis unit 44. The determination unit 41 creates a determination result of validity / invalidity of a carrier wave including the determination carrier wave and the analysis carrier wave received by the GNSS receivers 24 and 34 or obtains the determination result. The first effective period determination unit 42 determines a first effective period which is a period in which the determination result is estimated to be effective in the stellar date cycle, based on the determination result of the determination carrier. The second valid period determination unit 43 excludes from the start time of the first valid period to after the first period, and further excludes the end time of the first valid period to the second period before the second valid period. Decide. The baseline analysis unit 44 performs baseline analysis using the analysis carrier wave received during the second valid period and for which the determination result is valid. In addition, the GNSS analysis device 25 executes the GNSS analysis program to perform the above-described processing, whereby the GNSS analysis method is performed.

  Moreover, the GNSS analysis system 1 of the above-mentioned embodiment is provided with the GNSS analysis device 25, the GNSS antenna 20 arrange | positioned at a reference station, and the GNSS antenna 30 arrange | positioned at an observation station. The GNSS analysis device 25 calculates the relative displacement of the observation station with respect to the reference station based on the baseline vector obtained by performing the baseline analysis.

  As a result, baseline analysis is performed using the analysis carrier wave received in the second valid period excluding the start and end times of the first valid period, and therefore the influence of diffraction and multipath can be suppressed. it can. In addition, since the present technology can be applied even if the conditions of the obstacles of the reference station and the observation station are not the same, the versatility is high.

  In the GNSS analysis device 25 of the above embodiment, the first effective period determination unit 42 determines the first effective period based on the determination result of the determination carrier at least one stellar day before the stellar date when the analysis carrier is received. Decide.

  As a result, since the determination carrier wave can be determined before the analysis carrier wave is analyzed, baseline analysis can be performed at an early timing.

  Further, in the GNSS analysis device 25 of the above embodiment, the determination unit 41 acquires the determination result output from the GNSS receivers 24 and 34 for determination.

  Thereby, the processing amount of the processing performed on the GNSS analysis device 25 side can be reduced.

  Further, in the GNSS analysis device 25 of the above-described modified example, the determination unit 41 creates the determination result of the validity / invalidity of the carrier based on the SN ratio of the carrier (the determination carrier or the analysis carrier).

  Thereby, even if the GNSS receivers 24 and 34 do not have the function of determining the validity / invalidity of the carrier wave, the present technology can be applied.

  Further, in the GNSS analysis device 25 of the above-described embodiment, the first effective period determination unit 42 excludes, from the first effective period, a period in which the determination result of the determination carrier wave is invalid at least one staring day.

  In the GNSS analysis device 25 of the above embodiment, the first validity period determination unit 42 determines that the determination result of the determination carrier wave is invalid in at least one of the determination result of at least one stellar day and the determination result of two stellar days before. Is excluded from the first validity period.

  As a result, on each stellar day, the influence of the obstacle often occurs at the same timing, so that by performing the above processing, it is possible to extract a highly reliable analysis carrier.

  Further, the GNSS analysis device 25 of the above embodiment has the following configuration. That is, processing for comparing the determination result of one stellar day before and the determination result of the two stellar day before is performed using a digital filter. The first validity period determination unit 42 processes forward the time series filtering process of processing the determination result of one stellar day and the determination result of the two stellar day according to time series, the determination result of one stellar day and two stellar days Both of the determination result and the reverse time series filtering process of processing in the reverse order of the time series are performed.

  A delay may occur only by performing forward time series filtering, and it may be difficult to estimate the amount of delay. In this regard, the delay can be canceled by further performing backward time-series filtering in addition to forward time-series filtering.

  Further, in the GNSS analysis device 25 of the above-described embodiment, the first validity period determination unit 42 excludes, from the first validity period, a period in which the determination result of the determination carrier wave continues for a predetermined period continuously at least one staring day.

  As a result, since only the period in which the determination carrier wave is effective can be set as the first effective period continuously for a predetermined period, it is possible to extract a more reliable analysis carrier wave.

  Although the preferred embodiment and modification of the present invention have been described above, the above configuration can be modified as follows, for example.

  In the above embodiment, the determination results of one stellar day and two stellar days are used, but the determination results of three stellar days may also be used. In this case, it is preferable to exclude from the first validity period the period invalidated by any one determination result from one stellar day to three stellar days. In addition, since the situation of the obstacle may change, it is preferable to use the latest determination result, but the determination result before three stellar days (for example, one month ago) may be used.

  In the above embodiment, as the first effective period determination process, a star date filter process, a forward time series filter process, a reverse time series filter process, and a stabilization process It is the composition which does all of. Instead of this, a method of combining one or more methods of the above processing may be used. For example, the operation amount can be reduced by omitting the two time series filter processes. In this case, by using the stellar day filter processing, it is possible to compare the determination carrier and the analysis carrier one day before the stellar, so that the analysis carrier received during a period invalid before one stellar day should not be used. it can.

  In the above embodiment, the present technique is used in both the reference station and the observation station because the positions of the observation station as well as the reference station do not change so much. For example, the observation station has high speed. In the case of moving at, since it is difficult to use the present technology in the observation station because the conditions of obstacles on a stellar day will not be the same, the present technology will be used only in the reference station.

  <Use of two types of determination results> In the above embodiment, the GNSS analysis apparatus 25 uses the determination result in which the GNSS receiver determines the validity / invalidity of the carrier wave and the S / N ratio, and the GNSS analysis device 25 performs the carrier wave validity / invalidity The modification using the determined determination result has been described. By combining these determination results, for example, only the period in which the carrier is valid in both determination results may be treated as being valid. As a result, baseline analysis can be performed using a more reliable analysis carrier.

  <Real-Time Analysis and Re-analysis> The GNSS analysis system 1 of the above embodiment performs real-time analysis in which the analysis carrier is received and analyzed at the same timing. Therefore, the determination result of the determination carrier wave received before the measurement target stellar date is used to determine the first effective period. Instead of this, the GNSS analysis system 1 may be configured to re-analyze the analysis carrier waves after receiving the analysis carrier waves for a predetermined period (for example, one stellar day). Even in this case, the effects of diffraction and multipath can be suppressed by deleting the first period and the second period. In this case, when determining the first effective period, it is possible to use the determination result of the determination carrier wave received (that is, received on the same day) as the measurement target star day.

  When using the above reanalysis, it is possible to use the determination result of the stellar day after the stellar day on which the analysis carrier was received. That is, the first effective period determination unit 42 can determine the first effective period based on the determination result of the determination carrier wave at least one stellar day after the star date when the analysis carrier wave is received. As a result, determination carriers for various periods become available, which may make it possible to determine a more appropriate first effective period. Thus, in the present invention, the determination result before or after the stellar diurnal cycle with respect to the analysis time (in other words, the determination result of N sterility day, M stellar day, or the same day). It can be used.

  In the above embodiment, although the GNSS analysis device 25 is disposed inside the reference station measurement device 2, it may be disposed inside the observation station measurement device 3. In this case, data such as a carrier wave acquired by the reference station measurement device 2 is transmitted to the observation station measurement device 3. Further, the GNSS analysis device 25 may be disposed outside the reference station measurement device 2 and the observation station measurement device 3. In this case, the GNSS analysis device 25 may be able to communicate with the reference station measurement device 2 and the observation station measurement device 3, and when performing the above reanalysis, measurement is performed by the reference station measurement device 2 and the observation station measurement device 3 The data such as the carrier wave may be stored in a recording medium or the like, and this recording medium may be set in the GNSS analyzer 25 by a person.

Reference Signs List 1 GNSS analysis system 2 reference station measurement device 3 observation station measurement device 24 GNSS receiver 25 GNSS analysis device 26 storage unit 41 determination unit 42 first effective period determination unit 43 second effective period determination unit 44 baseline analysis unit

Claims (12)

A determination unit that creates a determination result of validity or invalidity of a carrier wave including a determination carrier and an analysis carrier received by the GNSS receiver, or obtains the determination result;
A first effective period determination unit that determines a first effective period, which is a period in which the determination result is estimated to be effective in a stellar date cycle, based on the determination result of the determination carrier;
The second effective period is determined by excluding the time from the start of the first effective period to the time after the first period and further excluding the time from the end of the first effective period to the time before the second period Department,
A baseline analysis unit that performs baseline analysis using the analysis carrier wave that is received during the second valid period and that is valid for the determination result;
A GNSS analysis apparatus comprising: The GNSS analysis device according to claim 1, wherein
The first effective period determination unit determines the first effective period based on the determination result of the determination carrier at least one star before the staring date when the analysis carrier is received. apparatus. The GNSS analysis device according to claim 1, wherein
The first effective period determination unit determines the first effective period based on the determination result of the determination carrier wave on the same day as the stellar day on which the analysis carrier wave is received, or at least one stellar day. Analysis device. The GNSS analysis device according to any one of claims 1 to 3, wherein
The said determination part acquires the determination result which the said GNSS receiver determines and outputs, The GNSS analysis apparatus characterized by the above-mentioned. The GNSS analysis device according to any one of claims 1 to 3, wherein
The GNSS analysis apparatus, wherein the determination unit creates a determination result of valid or invalid of the carrier based on an SN ratio of the carrier. The GNSS analyzer according to claim 2, wherein
The GNSS analysis device according to claim 1, wherein the first validity period determination unit excludes, from the first validity period, a period in which the determination result of the determination carrier wave is invalid at least one star before a star. The GNSS analyzer according to claim 6, wherein
The first validity period determination unit is characterized by excluding from the first validity period a period during which the determination result of the determination carrier wave is invalid at least one of the determination result of at least one stellar day and the determination result of the two stellar days before. GNSS analysis device to be. The GNSS analysis device according to claim 7, wherein
The first effective period determining unit
Perform processing using a digital filter to compare the determination result of one stellar day and the determination result of two stellar days,
The first validity period determination unit processes forward time series filter processing that processes the determination result of one stellar day and the determination result of two stellar days according to time series, the determination result of one stellar day, and the two stellar days before A GNSS analysis apparatus characterized in that it performs both of a determination result and an inverse time series filter process that processes the order in a reverse order to the time series. The GNSS analysis device according to claim 8, wherein
The GNSS analysis device according to claim 1, wherein the first valid period determination unit excludes a period during which the determination result of the determination carrier wave continues for a predetermined period and which is not valid at least one star before the star period. The GNSS analysis device according to any one of claims 1 to 9,
GNSS antenna located at the reference station,
GNSS antenna located at the observation station,
Equipped with
The GNSS analysis system, wherein the GNSS analysis device calculates relative displacement of the observation station with respect to the reference station based on a baseline vector obtained by performing the baseline analysis. Create a determination result of valid or invalid of the determination carrier and the analysis carrier received by the GNSS receiver, or obtain the determination result;
Based on the determination result of the determination carrier, a first effective period which is a period in which the determination result is estimated to be effective in the stellar date cycle is determined;
A second effective period is determined by excluding the time from the start of the first effective period to the time after the first period, and further excluding the time from the end of the first effective period to the time before the second period,
A GNSS analysis method comprising: performing a baseline analysis using the analysis carrier wave that is received during the second valid period and whose determination result is valid. Create a determination result of valid or invalid of the determination carrier and the analysis carrier received by the GNSS receiver, or obtain the determination result;
Based on the determination result of the determination carrier, a first effective period which is a period in which the determination result is estimated to be effective in the stellar date cycle is determined;
A second effective period is determined by excluding the time from the start of the first effective period to the time after the first period, and further excluding the time from the end of the first effective period to the time before the second period,
A GNSS analysis program comprising a process of performing a baseline analysis using the analysis carrier wave which is the analysis carrier wave received during the second valid period and whose determination result is valid.

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