Satellite navigation receiver

Abstract

To allow one satellite navigation receiver to simultaneously acquire calculation results based on different positioning methods, calculation conditions, or calculation parameters.SOLUTION: For a satellite navigation receiver that measures its own position using satellite navigation systems, including the GPS by the United States and Japan's Quasi-Zenith Satellite System, multiple combinations of positioning methods, calculation conditions, and calculation parameters for positioning calculations will be maintained, and each of these will be applied to a set of distance measurements using a single ranging processing circuit to perform positioning calculations, and all calculation results obtained will be output, making it possible to simultaneously obtain calculation results using different positioning methods, calculation conditions, or calculation parameters by one satellite navigation receiver.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a satellite navigation receiver in the field of satellite navigation. [Background technology]

[0002] Satellite navigation systems that use satellites to measure position are collectively called GNSS (Global Navigation Satellite System), and a representative example is the US-based GPS (Global Positioning System). GNSS generally uses a satellite navigation receiver to receive positioning signals transmitted by satellites called navigation satellites, and calculates the receiver's position by measuring the distance between the navigation satellite and the receiver. The error between the calculated position and the true position is called the positioning error, and the statistical nature of the positioning error is called the positioning accuracy. Measuring position is called positioning, and the calculation process for this is called positioning calculation.

[0003] To calculate the position of a satellite navigation receiver, it is necessary to know the position of the navigation satellite that is transmitting the positioning signal, but the navigation satellite's orbital information required for this is superimposed on the positioning signal by the navigation satellite itself and transmitted. Because the orbital information is created by prediction, the position of the navigation satellite calculated in this way contains an error of up to several meters, which becomes a factor in positioning error when calculating the receiver's position as a position error of the navigation satellite.

[0004] The timing at which a navigation satellite transmits a positioning signal is predetermined, and the navigation satellite transmits the positioning signal based on the time on its own clock. Although a highly accurate atomic clock is used for this clock, slight time discrepancies are unavoidable, so the satellite navigation receiver requires information about the time indicated by the navigation satellite's clock. This clock information is superimposed on the positioning signal by the navigation satellite itself and transmitted. Because the clock information is created by prediction, the timing of transmitting the positioning signal calculated using this method contains an error equivalent to a few meters in distance, and this becomes a factor in positioning error when calculating the receiver's position as a clock error on the navigation satellite.

[0005] Before the positioning signal reaches the ground, various factors, such as propagation delays caused by the atmosphere in the sky and the contamination of reflected waves near the ground, cause errors in the distance measurement. All of these factors also contribute to positioning errors when calculating the position of a satellite navigation receiver.

[0006] To reduce positioning errors, a receiver is installed at a fixed reference station on the ground, and correction information is generated from the distance measured by this to compensate for distance measurement errors caused by various error factors. This information is then provided to the user, who then corrects the distance measured at the user station using the correction information, thereby reducing positioning errors at the user station. This method is called Differential GPS (DGPS). To distinguish it from DGPS, the method of calculating the position of a user station without applying correction information is called standalone positioning.

[0007] In both point positioning and DGPS, various methods have been developed to further reduce positioning errors, and many calculation conditions and parameters are involved when a satellite navigation receiver calculates its own position. Generally, these calculation conditions and parameters can be set in a satellite navigation receiver, and the receiver outputs the position obtained by calculation applying the set calculation conditions and parameters. The types and ranges of calculation conditions and calculation parameters that can be set in a receiver, as well as the specific setting method, are determined by the model of the receiver.

[0008] Some satellite navigation receivers that use DGPS output the position determined by DGPS if DGPS is executed correctly, and output the position determined by stand-alone positioning if DGPS is not executed. When this output is performed, it is normal to include identification information indicating whether the result is based on stand-alone positioning or DGPS.

[0009] In addition to the calculated position, the output of a satellite navigation receiver usually includes information about the positioning accuracy and a protection level. Information about the positioning accuracy is calculated based on the approximate range accuracy predicted by the position of navigation satellites in the sky and the elevation angle of the navigation satellites. The protection level is an index used to ensure the integrity of the position output by the satellite navigation receiver, and generally corresponds to a 99.99999% confidence interval of the positioning error.

[0010] However, satellite navigation receivers produce different position outputs depending on the positioning method, calculation conditions, or calculation parameters, resulting in different positioning errors and accuracy. Since these are set in advance before the receiver is operated, if it is desired to simultaneously obtain calculation results using different positioning methods, calculation conditions, or calculation parameters, multiple receivers with different settings may be operated in parallel. In this case, it is common to distribute the signal received by the same antenna to the multiple receivers to ensure that the receivers' operating conditions are the same. Alternatively, a single receiver may be used to repeatedly operate with different settings. In this case, for example, an RF recorder capable of recording the positioning signals transmitted by the satellite navigation system as they are is used, and the signals are played back multiple times and input into the satellite navigation receiver.

[0011] However, the method using multiple receivers cannot avoid the influence of individual differences between receivers, and depending on the application, the increase in the total weight of the receivers can be a problem. The method of repeatedly operating one receiver cannot obtain results in real time, so it cannot be used for navigation of moving objects, and the weight of the RF recorder can be a problem. [Prior art documents] [Non-patent literature]

[0012] [Non-Patent Document 1] TrimbleAccess Help Portal, Satellite Information, May 2024 (https: / / help.trimblegeospatial.com / TrimbleAccess / latest / ja / GNSS-satellites.htm) [Non-patent document 2] Genoa Co., Ltd., Positioning methods to improve accuracy, accessed May 2024 (https: / / www.jenoba.jp / technical / gnss04 / ) [Non-patent document 3] Kiyoshi Nagase et al., A Study on Performance Evaluation Methods for GNSS Receivers in Actual Use Environments, Proceedings of the Civil Engineering Informatics Symposium, vol. 40, October 2015 Summary of the Invention [Problem to be solved by the invention]

[0013] In satellite navigation receivers, different positions are generally obtained as results depending on the positioning calculation method, calculation conditions, and calculation parameters. Since these are set in advance before operating the receiver, if you want to simultaneously obtain calculation results using different positioning methods, calculation conditions, or calculation parameters, it has been necessary to operate multiple receivers in parallel or to operate one receiver repeatedly. The objective of this invention is to It is to provide multiple calculation results using different positioning methods, calculation conditions, or calculation parameters simultaneously from one receiver. . [Means for solving the problem]

[0014] Non-Patent Document 1 describes a setting method for selecting a navigation satellite to be used in a satellite navigation receiver. As explained, the selection of a navigation satellite to be used is an item that can be set depending on the model of the receiver.

[0015] Non-Patent Document 2 explains that there are multiple methods for calculating positioning in satellite navigation receivers. Some receivers are compatible with several of these methods, allowing users to select the positioning method.

[0016] However, the technical contents described in Non-Patent Document 1 and Non-Patent Document 2 merely indicate that there are various combinations of positioning calculation methods, calculation conditions, or calculation parameters, and do not solve the problem that the present invention aims to solve.

[0017] Non-Patent Document 3 states that by using an RF recorder that can record the positioning signals transmitted by the satellite navigation system as they are, and then playing back the signals multiple times and inputting them into a satellite navigation receiver, "it is possible to compare the performance of receivers under the same conditions." As described in

[0010] , in addition to using this method, a common method for comparing and evaluating the performance of receivers with different settings under the same conditions is to distribute the signal received by the same antenna to multiple receivers and operate them in parallel.

[0018] The same situation applies when it is desired to obtain calculation results for different positioning methods, calculation conditions, or calculation parameters from a certain satellite navigation receiver. In other words, there has been no satellite navigation receiver that can simultaneously provide multiple calculation results using different positioning methods, calculation conditions, or calculation parameters from a single receiver.

[0019] The technical content described in Non-Patent Document 3 merely describes a method of repeatedly operating one satellite navigation receiver to obtain multiple calculation results based on positioning calculation methods, calculation conditions, or calculation parameters, and does not solve the problem that this invention aims to solve.

[0020] The present invention solves the above-mentioned problem by storing multiple combinations of positioning calculation methods, calculation conditions, and calculation parameters in a satellite navigation receiver, applying each of these to calculate position, and utilizing the multiple calculation results obtained.

[0021] The invention of claim 1 is a satellite navigation receiver that receives positioning signals transmitted by multiple navigation satellites, measures the distance between them, and calculates its own position using the measured distance values ​​obtained. The receiver holds multiple combinations of positioning methods, calculation conditions, and calculation parameters when calculating its own position, and stores each of these combinations as , a set of distance measurements by a single distance measurement processing circuit This satellite navigation receiver is characterized by applying the algorithm to calculate its own position and outputting all the calculation results obtained. [Effects of the Invention]

[0022] The satellite navigation receiver of the present invention holds multiple combinations of positioning calculation methods, calculation conditions, or calculation parameters, and , a set of distance measurements by a single distance measurement processing circuit It outputs all or any one of the applied calculation results, Multiple calculation results using different positioning methods, calculation conditions, or calculation parameters can be provided simultaneously by one receiver. . [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a schematic diagram illustrating an embodiment of the present invention, for explaining the operation of a satellite navigation receiver according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] Specific embodiments of the present invention will be described in detail below with reference to the drawings. [Example]

[0025] First, an embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a schematic diagram for explaining the operation of the satellite navigation receiver of this embodiment.

[0026] In FIG. 1, navigation satellites 1 (1a, 1b, etc.) each transmit a positioning signal.

[0027] The satellite navigation receiver 2 receives the positioning signals transmitted by the navigation satellites 1 (1a, 1b, . . . ) by means of an antenna 3, and measures the distance to each navigation satellite by means of a distance measurement processing circuit 4. The satellite navigation receiver 2 has only one distance measurement processing circuit 4 .

[0028] The positioning calculation processing unit 6 (6a, 6b, 6c) provided in the satellite navigation receiver 2 performs positioning calculations using distance information measured by the distance measurement processing circuit 4, based on the positioning calculation settings 5 ​​(5a, 5b, 5c) that hold combinations of positioning methods, calculation conditions, and calculation parameters that are prepared for each. Note that although an example is shown here in which there are three types of positioning calculation settings, the number of types of positioning calculation settings is not limited to three, and any number of types greater than or equal to two may be used.

[0029] The positioning calculation processing units 6 (6a, 6b, 6c) each output a position output 7 (7a, 7b, 7c). The calculation result corresponding to the positioning calculation setting 5a is output to the position output 7a, the calculation result corresponding to the positioning calculation setting 5b is output to the position output 7b, and the calculation result corresponding to the positioning calculation setting 5c ​​is output to the position output 7c. A user of the satellite navigation receiver may select and use any of the outputs, or may use all of the outputs. [Industrial Applicability]

[0030] By using the satellite navigation receiver of the present invention, Multiple calculation results using different positioning methods, calculation conditions, or calculation parameters can be obtained simultaneously with one receiver. Previously, to obtain such calculation results, it was necessary to operate multiple receivers in parallel or to operate one receiver repeatedly, but with the present invention, results can be obtained simultaneously with one receiver. [Explanation of symbols]

[0031] 1(1a,1b···) Navigation satellite 2 antennas 3 Satellite navigation receiver 4. Distance measurement processing circuit 5(5a,5b,5c) Positioning calculation settings 6(6a, 6b, 6c) Positioning calculation processing unit 7(7a,7b,7c) Position output

Claims

1. A satellite navigation receiver receives positioning signals transmitted by multiple navigation satellites, measures the distances between them, and calculates its own position using the distance measurements obtained. storing a plurality of combinations of positioning methods, calculation conditions, and calculation parameters when calculating the own position; Apply each of these to calculate your position, A satellite navigation receiver that outputs all the calculation results obtained.

2. When outputting the calculation results, 2. A satellite navigation receiver according to claim 1, wherein each calculation result is output with information attached thereto that identifies which of said combinations of positioning method, calculation conditions and calculation parameters the result corresponds to.

3. When outputting the calculation results, 3. The satellite navigation receiver according to claim 1, wherein each calculation result is output to a pre-assigned output communication line depending on which of the combinations of positioning method, calculation conditions and calculation parameters the result corresponds to.

4. 4. The satellite navigation receiver according to claim 3, wherein the output destination communication line is one that is physically one communication line but is logically distinguished as a plurality of communication paths.

5. A satellite navigation receiver receives positioning signals transmitted by multiple navigation satellites, measures the distances between them, and calculates its own position using the distance measurements obtained. storing a plurality of combinations of positioning methods, calculation conditions, and calculation parameters when calculating the own position; Apply each of these to calculate your position, A satellite navigation receiver characterized by selecting and outputting one of the valid calculation results from among all the calculation results obtained.

6. When selecting and outputting one of the above, 6. A satellite navigation receiver according to claim 5, wherein the calculation result to be output is accompanied by information identifying which of the combinations of said positioning method, calculation conditions and calculation parameters the result corresponds to.

7. When selecting and outputting one of the above, 7. The satellite navigation receiver according to claim 5, wherein the selection is made using information about the positioning accuracy included in the valid calculation result.

8. When selecting and outputting one of the above, 7. A satellite navigation receiver according to claim 5, wherein the selection is made using a protection level contained in the valid calculation result.

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