A satellite positioning receiver long code signal capture test method

Abstract

The present invention discloses a method and system for testing the capture of a long code signal of a satellite positioning receiver, the method comprising: setting a scene with a navigation signal simulation source; a host computer obtains a rough position and almanac information, and sends it to a receiver; adjusting an adjustable attenuator, and determining the test signal level; the host computer generates a random time offset, and sends it to a timing board, and controls the timing board to perform timing on the receiver; the host computer sends a capture instruction to the receiver; the receiver performs a capture process, calculates the time difference, and returns it to the host computer; the host computer determines the time difference, determines whether the capture is successful or failed, and calculates the capture time at the same time. The present invention can directly test the capture module of the receiver, and then evaluate the capture sensitivity, capture time, and dynamic adaptability, and provide an effective basis for the design, development, and performance improvement of the satellite positioning receiver.

Description

Technical Field

[0001] The invention relates to the field of satellite positioning and navigation, and in particular to a long code signal capture test method and system for a satellite positioning receiver. Background Art

[0002] Satellite navigation system signals are divided into short code signals and long code signals. The ranging code of short code signals generally adopts periodic pseudo code, while the ranging code of long code signals has no periodicity. The capture of satellite signals is essentially the capture of the ranging code modulated by them, so the capture of long code signals is the capture of their non-periodic ranging codes.

[0003] The capture performance of satellite positioning receiver mainly includes capture sensitivity, capture time, and dynamic range. Capture sensitivity refers to the capture module's ability to capture the signal level, capture time evaluates the speed of the capture module to capture the signal, and dynamic range evaluates the capture module's adaptability to dynamic signals. The capture test of satellite positioning receivers usually only tests the capture sensitivity, using a method of evaluating positioning within a limited time with a given signal level, and the capture time is no longer tested separately. The positioning of the receiver involves not only the capture of the signal, but also the observation quantity and the telegram. The telegram is divided into two parts: decoding and analysis. Therefore, the method of evaluating positioning cannot truly reflect the capture performance.

[0004] During the design and development phase or modular testing phase of the receiver, the capture time, capture signal level, and dynamic range should be fully tested to truly evaluate the receiver's capture performance. Due to the non-periodic nature of the ranging code, the capture of the long code signal requires given time information and a given time uncertainty range. Based on the characteristics of long code signal capture, it is very meaningful to design a test method to conduct a large number of repeated tests to test and evaluate the long code signal capture performance in the most direct way. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and to provide a method and system for testing the capture of long code signals of a satellite positioning receiver.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A satellite positioning receiver long code signal capture test method, comprising the following steps:

[0008] Step 1: Navigation signal simulation source setting scene;

[0009] Step 2: The host computer obtains the approximate location and almanac information;

[0010] Step 3: Adjust the adjustable attenuator to determine the test signal level;

[0011] Step 4: The host computer sends the approximate position and almanac information to the satellite positioning receiver;

[0012] Step 5: The host computer generates a random time offset and sends it to the timing board;

[0013] Step 6: The host computer controls the timing board to provide timing to the receiver;

[0014] Step 7: The host computer sends a capture command to the satellite positioning receiver;

[0015] Step 8: The satellite positioning receiver performs capture processing, calculates the time difference, and returns it to the host computer;

[0016] Step 9: The host computer determines the time difference, determines whether the capture is successful or failed, and calculates the capture time.

[0017] Furthermore, the host computer is installed with test software, and the approximate position and almanac information are obtained according to the scenario set by the navigation signal simulation source.

[0018] Furthermore, the capture instruction includes the capture satellite number, signal component and capture mode.

[0019] Furthermore, the step 8 specifically includes the following sub-steps:

[0020] Step 801: The satellite positioning receiver captures the satellite signal according to the capture instruction, and obtains the corresponding time offset after capturing the satellite signal;

[0021] Step 802: Calculate the propagation delay according to the approximate position and the almanac information, and subtract the time offset from the propagation delay to obtain the time difference;

[0022] Step 803: Return the time difference to the host computer.

[0023] Furthermore, the step 9 specifically includes the following sub-steps:

[0024] Step 901: The host computer software determines the time difference and compares it with the random time offset of this test;

[0025] Step 902: If the difference between the two is within the allowed range, it is determined that the capture is successful, and the capture time is obtained according to the time of sending the capture instruction and the time when the host computer returns;

[0026] Step 903: If it is out of range, it is determined that the capture has failed.

[0027] Furthermore, the scene set by the navigation signal simulation source includes various dynamic scenes; if the scene is switched to other dynamic scenes, steps 1 to 9 are repeated to test and count the capture success rate and capture time of the satellite signal receiver under the dynamic scene and the signal level.

[0028] Further, steps 1 to 9 are repeated, and the adjustable attenuator is adjusted in step 3 to output signals with different signal strengths, so as to test the capture sensitivity in this scenario.

[0029] A satellite positioning receiver long code signal capture test system, comprising a satellite positioning receiver, a navigation signal simulation source, a timing board, a host computer software and an adjustable attenuator;

[0030] The navigation signal simulation source is connected to an adjustable attenuator to output the satellite signal to the adjustable attenuator;

[0031] The host computer software obtains the approximate position and almanac information according to the scene set by the navigation signal simulation source;

[0032] The timing board is connected to the host computer software and the satellite positioning receiver, receives the random time offset generated by the host computer software, and provides timing to the satellite positioning receiver;

[0033] The adjustable attenuator is connected to the satellite positioning receiver and adjusts the signal strength according to the test level so that the signal level from the analog source to the satellite positioning receiver meets the test requirements;

[0034] The host computer software is connected to a satellite positioning receiver, and the host computer software sends the approximate position and satellite almanac to the satellite positioning receiver. After completing the timing, the host computer software sends a capture instruction to the satellite positioning receiver; the satellite positioning receiver captures and processes the specified satellite signal according to the capture instruction, and returns the time difference to the host computer; the host computer determines whether the signal capture is successful based on the time difference, and calculates the capture time.

[0035] The beneficial effects of the present invention are as follows: the present invention performs a large number of repeated tests on long code signals. Compared with the test for evaluating positioning, it can directly test the capture module of the receiver, and then evaluate the capture sensitivity, capture time and dynamic adaptability, providing an effective basis for the design, development and performance improvement of satellite positioning receivers. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0037] Figure 1 It is a capture test flow chart of the present invention.

[0038] Figure 2 It is a block diagram of the capture test system of the present invention. DETAILED DESCRIPTION

[0039] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] In this embodiment, Figure 1 As shown, a satellite positioning receiver long code signal capture test method includes the following steps:

[0042] Step 1: Navigation signal simulation source setting scene;

[0043] Step 2: The host computer obtains the approximate location and almanac information;

[0044] Step 3: Adjust the adjustable attenuator to determine the test signal level;

[0045] Step 4: The host computer sends the approximate position and almanac information to the satellite positioning receiver;

[0046] Step 5: The host computer generates a random time offset and sends it to the timing board;

[0047] Step 6: The host computer controls the timing board to provide timing to the receiver;

[0048] Step 7: The host computer sends a capture command to the satellite positioning receiver; the capture command includes the capture satellite number, signal component and capture method.

[0049] Step 8: The satellite positioning receiver performs capture processing, calculates the time difference, and returns it to the host computer;

[0050] Among them, step 8 is specifically as follows:

[0051] The satellite positioning receiver captures and processes the satellite signal according to the capture instruction, and obtains the corresponding time offset after capturing the satellite signal;

[0052] Calculate the propagation delay based on the approximate position and almanac information, and subtract the time offset from the propagation delay to obtain the time difference;

[0053] Return the time difference to the host computer.

[0054] Step 9: The host computer determines the time difference, determines whether the capture is successful or failed, and calculates the capture time;

[0055] Among them, step 9 is specifically as follows:

[0056] The host computer software determines the time difference and compares it with the random time offset of this test;

[0057] If the difference between the two is within the allowed range, the capture is considered successful. At the same time, the capture time is obtained based on the time when the capture command is sent and the time when the host computer returns.

[0058] If it exceeds the range, the capture is considered a failure;

[0059] Among them, the host computer is installed with test software, and the approximate position and almanac information are obtained according to the scenario set by the navigation signal simulation source.

[0060] Among them, the scenes set by the navigation signal simulation source include various dynamic scenes; if the scene is switched to a dynamic scene, steps 1 to 9 are repeated to test and count the capture success rate and capture time of the satellite signal receiver under the dynamic scene and the signal level.

[0061] Adjust the adjustable attenuator to output signals with different signal strengths, and repeat steps 1 to 9 to test and evaluate the capture sensitivity in this scenario.

[0062] A satellite positioning receiver long code signal capture test system, comprising a satellite positioning receiver, a navigation signal simulation source, a timing board, a host computer software and an adjustable attenuator;

[0063] The navigation signal simulation source is connected to the adjustable attenuator, and the satellite signal is output to the adjustable attenuator;

[0064] The host computer software obtains the approximate position and satellite almanac information according to the scenario set by the navigation signal simulation source;

[0065] The timing board connects the host computer software and the satellite positioning receiver, receives the random time offset generated by the host computer software, and provides timing to the satellite positioning receiver, providing the time information required for long code capture;

[0066] The adjustable attenuator is used to adjust the strength of the analog source output signal. According to the test level, the signal strength is adjusted so that the signal level of the analog source reaching the satellite positioning receiver meets the test requirements;

[0067] The upper computer software is connected to the satellite positioning receiver, and the upper computer software sends the approximate position and satellite almanac to the satellite positioning receiver. After completing the timing, the upper computer software sends a capture instruction to the satellite positioning receiver; the satellite positioning receiver captures and processes the specified satellite signal according to the capture instruction, and returns the time difference to the upper computer; the upper computer determines whether the signal capture is successful based on the time difference, and calculates the capture time.

[0068] In this embodiment, a long code signal of the Beidou global system is taken as an example for specific description, and the process is as follows:

[0069] The navigation signal simulation source sets the scene and copies the approximate position and satellite almanac information to the host computer software. Taking the horizontal circular low-dynamic scene as an example, the host computer software obtains the approximate position coordinates and the almanac information of the satellite in this scene.

[0070] Taking the input signal level to be measured as A (in dBm) as an example, the adjustable attenuator is adjusted so that the input signal level from the analog source to the receiver reaches A (in dBm).

[0071] The host computer software sends the approximate position and almanac information to the receiver, and generates a random time offset, and sends the offset to the timing board; the timing board uses the time offset to offset the output time. The host computer software controls the timing board to provide time to the receiver. Taking the time uncertainty of ±5s as an example, the time offset generated by the host computer is 2s, and the time information output by the timing board is offset by 2s relative to the accurate time.

[0072] The host computer software sends a capture command to the receiver, including the capture satellite number, signal component, and capture mode. Taking a long code signal of the Beidou global system as an example, the satellite number and signal component are set, the capture mode is direct capture, and the time uncertainty is ±5s.

[0073] The receiver captures the designated satellite signal according to the capture command, obtains the corresponding time offset after successful capture, and calculates the propagation delay according to the approximate position and almanac information, subtracts the time offset from the propagation delay to obtain the time difference, and finally returns the time difference to the host computer. Taking a long code signal of the Beidou global system as an example, after successful capture, the time offset X is obtained, and then the propagation delay Y is calculated. Assuming that the time offset after deducting the propagation delay is 1.996s, this value is returned to the host computer.

[0074] The host computer software determines the time difference and compares it with the random deviation time to determine whether the capture is successful. Taking a long code signal of the Beidou global system as an example, the allowable range of the difference between the time offset and the receiver return value is set to 5ms. If the difference between the returned 1.996s and 2s is 4ms, which is within the allowable range, the capture is determined to be successful. The host computer obtains the capture time based on the time when the capture command is sent and the time returned by the host computer. Assuming that the difference between the time offset and the receiver return value exceeds 5ms, the capture is determined to have failed.

[0075] By repeating the above process, the capture success rate of the receiver at the A level (in dBm) in a static scenario can be measured. At the same time, the host computer averages the capture time of repeated capture tests to obtain the capture time in this state.

[0076] Taking a long code signal of the BeiDou global system as an example, assuming that the capture sensitivity in a static scene needs to be tested, the signal level from the analog source to the receiver can be gradually reduced by adjusting the adjustable attenuator, and the above process is repeated until the measured capture success rate is below the index. Assuming that the capture success rate is required to be 80%, and when the signal level is reduced to B (in dBm), the capture success rate is lower than 80%, then the capture sensitivity of a long code signal of the BeiDou global system in a static scene is considered to be (B+1) (in dBm).

[0077] By changing the dynamic scene of the simulated source and repeating the above process, the capture sensitivity and capture time under different dynamic scenes can be evaluated.

[0078] It should be noted that, for the above-mentioned various method embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations, but those skilled in the art should be aware that this application is not limited by the order of the actions described, because according to this application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and units involved are not necessarily required by this application.

[0079] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0080] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. The storage medium can be a disk, an optical disk, a ROM, a RAM, etc.

[0081] The above disclosure is only the preferred embodiment of the present invention, which certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A satellite positioning receiver long code signal acquisition test method, characterized in that: The following steps are involved: Step 1: Navigation signal simulation source setting scene; Step 2: The host computer obtains the approximate location and almanac information; Step 3: Adjust the adjustable attenuator to determine the test signal level; Step 4: The host computer sends the approximate position and almanac information to the satellite positioning receiver; Step 5: The host computer generates a random time offset and sends it to the timing board; Step 6: The host computer controls the timing board to provide timing to the receiver; Step 7: The host computer sends a capture command to the satellite positioning receiver; Step 8: The satellite positioning receiver performs capture processing, calculates the time difference, and returns it to the host computer; Step 9: The host computer determines the time difference, determines whether the capture is successful or failed, and calculates the capture time.

2. A satellite positioning receiver long code signal acquisition test method according to claim 1, characterized in that: The host computer is installed with test software, and the approximate position and almanac information are obtained according to the scenario set by the navigation signal simulation source.

3. A satellite positioning receiver long code signal acquisition test method according to claim 1, characterized in that: The capture instruction includes the capture satellite number, signal component and capture mode.

4. A satellite positioning receiver long code signal acquisition test method according to claim 1, characterized in that: The step 8 specifically includes the following sub-steps: Step 801: The satellite positioning receiver captures the satellite signal according to the capture instruction, and obtains the corresponding time offset after capturing the satellite signal; Step 802: Calculate the propagation delay according to the approximate position and the almanac information, and subtract the time offset from the propagation delay to obtain the time difference; Step 803: Return the time difference to the host computer.

5. A satellite positioning receiver long code signal acquisition test method according to claim 1, characterized in that: The step 9 specifically includes the following sub-steps: Step 901: The host computer software determines the time difference and compares it with the random time offset of this test; Step 902: If the difference between the two is within the allowed range, it is determined that the capture is successful, and the capture time is obtained according to the time of sending the capture instruction and the time when the host computer returns; Step 903: If it is out of range, it is determined that the capture has failed.

6. A satellite positioning receiver long code signal acquisition test method according to claim 1, characterized in that: The scenarios set by the navigation signal simulation source include various dynamic scenarios; If the scene is switched to another dynamic scene, steps 1 to 9 are repeated to test and count the capture success rate and capture time of the satellite signal receiver under the dynamic scene and the signal level.

7. A satellite positioning receiver long code signal acquisition test method according to claim 1, characterized in that: Repeat steps 1 to 9, and adjust the adjustable attenuator in step 3 to output signals with different signal strengths to test the capture sensitivity in this scenario.

8. A test system using the method according to any one of claims 1 to 7, characterized in that: Includes satellite positioning receiver, navigation signal simulation source, timing board, host computer software and adjustable attenuator; The navigation signal simulation source is connected to an adjustable attenuator to output the satellite signal to the adjustable attenuator; The host computer software obtains the approximate position and almanac information according to the scene set by the navigation signal simulation source; The timing board is connected to the host computer software and the satellite positioning receiver, receives the random time offset generated by the host computer software, and provides timing to the satellite positioning receiver; The adjustable attenuator is connected to the satellite positioning receiver and adjusts the signal strength according to the test level so that the signal level from the analog source to the satellite positioning receiver meets the test requirements; The host computer software is connected to a satellite positioning receiver, and the host computer software sends the approximate position and satellite almanac to the satellite positioning receiver, and after completing the timing, sends a capture instruction to the satellite positioning receiver; The satellite positioning receiver captures the designated satellite signal according to the capture instruction and returns the time difference to the host computer; the host computer determines whether the signal capture is successful according to the time difference and calculates the capture time.

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