CN107957587B - A multi-channel differential multi-mode satellite navigation and positioning method and device - Google Patents

Abstract

The invention discloses a multi-channel differential multi-mode satellite navigation and positioning method and device. After receiving the difference information sent by the reference station and generating a check code, the master communication verification terminal sends the difference information and the verification code to the slave communication verification terminal. Verification terminal, the slave communication verification terminal performs integrity verification on the differential information according to the received differential information and verification code, the mobile station decides whether to send confirmation information to the master communication verification terminal according to the received verification result, the master The communication verification terminal maintains the current communication mode or switches the communication mode according to whether the confirmation information is received, and finally the mobile station calculates the positioning information and sends it to the reference station. By pre-checking the integrity of the differential information to determine which communication method to use, it can ensure that the differential information data does not leak packets, improve the positioning accuracy, and is suitable for multi-channel differential multi-mode satellite navigation positioning.

Description

A multi-channel differential multi-mode satellite navigation positioning method and device

Technical Field

The present invention relates to the field of GNSS communication technology, and in particular to a multi-path differential multi-mode satellite navigation positioning method and device.

Background Art

High-precision GNSS measurements must use carrier phase observations. RTK (Real-Time Kinematic) positioning technology is a real-time dynamic positioning technology based on carrier phase observations. It can provide real-time three-dimensional positioning results of the measuring station in the specified coordinate system and achieve centimeter-level accuracy. In RTK operation mode, the base station transmits its observations and station coordinate information to the mobile station through the data link. However, the biggest problem encountered by RTK technology in application is that the effective range is limited by the differential communication link. The spatial correlation of GNSS errors gradually loses linearity as the distance between the reference station and the mobile station increases. Therefore, at longer distances (single frequency>10km, dual frequency>30km), higher requirements are placed on the communication link for differential signal transmission.

In the prior art, communication links for differential signal transmission usually adopt two modes: radio station and mobile network communication.

Traditional differential signal transmission mostly relies on radio stations. The transmission distance limit of radio stations makes the operation distance of traditional RTK very limited. To increase the transmission distance, the power of the radio station must be increased. The increase in power will inevitably lead to an increase in the size and weight of the equipment. However, radio stations with large volume and mass are also difficult to apply to micro-UAVs. Therefore, a small and light high-precision positioning system is urgently needed.

The key to RTK technology lies in data processing technology and data transmission technology. RTK positioning requires the base station receiver to transmit observation data (pseudo-range observation values, phase observation values) and known data to the mobile station receiver in real time. The amount of data is relatively large, and generally requires a baud rate of more than 9600, which is not difficult to achieve on a radio station. However, when using a radio as a transmission data link, there must be no obvious obstacles between the reference station and the mobile station, and the effective transmission distance is limited. The effective transmission distance when using an ultra-high power radio is only about 8km, and the mass and volume are also large, which brings many problems to the location collection of large farms or large mines.

Common 2G wireless communication protocols include GSM frequency division multiple access and code division multiple access, which have slow transmission speeds. 3G network is the third generation of wireless cellular telephone communication protocol, which mainly develops high-bandwidth data communication based on 2G. The general data communication bandwidth of 3G is above 500Kb/s. At present, there are three commonly used 3G standards: WCDMA, CDMA2000, and TD-SCDMA. The transmission speed is relatively fast, which can well meet the needs of mobile Internet access. 4G network refers to the fourth generation of wireless cellular telephone communication protocol, which can download at a speed of 100Mbps and upload at a speed of 20Mbps, and can meet the requirements of almost all users for wireless services. As of January 2016, China Mobile has built a total of 1.052 million base stations in rural areas across the country, accounting for 39% of the total number of base stations in the network. Among them, the number of 2G base stations is 481,000, covering 592,000 administrative villages, and the coverage rate of administrative villages has reached 99%; the number of 4G base stations is 409,000, covering about 400,000 administrative villages, and the coverage rate of administrative villages has reached 65%. Now, using network communication as the differential data link of RTK, a high-precision positioning method, can greatly improve the working efficiency of RTK.

For example, the method, device and system for remotely controlling the RTK system through the 3G network, which is patented with application number CN201110455887.X, uses the WCDMA (3G) communication method to greatly improve the data transmission rate. However, it is reported that the 3G network has unstable connection in most areas. Using the 3G network as the differential data link of the differential GNSS will result in low positioning efficiency and positioning accuracy of the differential GNSS. In addition, in the high-speed movement of the moving carrier carrying the GNSS positioning system, especially the high-precision differential GNSS positioning, the refresh rate is low, which makes it difficult to meet the positioning refresh rate requirements of the high-speed carrier.

The two types of differential information transmission communication links have their own advantages and disadvantages. The radio station does not require additional channel usage fees, but its size and mass increase with the increase of transmission distance, making it difficult to use on micro drones; the mobile network communication method can meet the needs of long-distance communication, but it needs to pay channel usage fees, and the data transmission quality is uncertain and prone to delays. To improve the signal transmission quality and reliability of the communication link, a new differential information transmission method is needed.

In addition, the output frequency of positioning data is one of the cost-influencing factors of existing RTK-GNSS systems. RTK-GNSS positioning systems with high output frequency are usually more expensive.

Summary of the invention

In order to overcome at least one of the defects of the above-mentioned prior art, the present invention provides a multi-channel differential multi-mode satellite navigation positioning method and device, which can automatically determine the validity of differential information and select a suitable communication mode, thereby improving positioning efficiency and positioning accuracy.

In order to achieve the purpose of the present invention, the following technical solutions are adopted:

A multi-path differential multi-mode satellite navigation positioning method comprises the following steps:

S1. The base station sends the differential information to the host communication verification terminal;

S2. The host communication verification terminal receives the differential information sent by the reference station, generates a verification code, and sends the differential information and the verification code to several slave communication verification terminals;

S3. The slave communication verification terminal receives the differential information and the check code sent by the host communication verification terminal, performs a check on the integrity of the differential information to obtain the check result, and sends the check result to several mobile stations;

S4. The mobile station decides whether to send a confirmation message to the host communication verification terminal based on the received verification result;

S5. The host communication verification terminal maintains the current communication mode or switches the communication mode according to whether the confirmation information is received, wherein the communication mode includes a network communication mode and a radio station communication mode;

S6. The mobile station calculates the positioning information output according to the differential information and sends it to the host communication verification terminal of the reference station through the slave communication verification terminal. The reference station obtains the positioning information of the mobile station through the host communication verification terminal.

Different communication modes have both advantages and disadvantages and different applicability. The transmission distance of the radio station communication mode is limited; the network connection is unstable when the network communication mode is adopted. Therefore, it is necessary to select a suitable communication mode in different scenarios. A variety of communication modes are integrated in the host communication verification terminal and the slave communication verification terminal, including the network communication mode and the radio station communication mode, so that the host communication verification terminal can select the corresponding differential communication link under different communication modes according to the integrity verification result of the differential information, so as to ensure the integrity of the differential information and improve the positioning efficiency and positioning accuracy.

If the integrity check result shows that the differential information is complete, the mobile station sends a confirmation message to the host communication verification terminal, and the host communication verification terminal maintains the current communication mode; if the integrity check result shows that the differential information is incomplete, the mobile station does not send a confirmation message to the host communication verification terminal, and the host communication verification terminal switches the communication mode.

The communication mode adopted by the host communication verification terminal and the slave communication verification terminal is consistent to ensure effective communication connection between the host communication verification terminal and the slave communication verification terminal. When the host communication verification terminal switches the communication mode, the slave communication verification terminal also switches the communication mode.

The host communication verification terminal can send differential information and verification codes to multiple slave communication verification terminals, and the slave communication verification terminal can send verification results to multiple mobile stations, thereby realizing one-to-many concurrent differential information of the base station, which can reduce the investment in the base station and reduce the cost of the overall system.

Furthermore, the mobile station can select different positioning modes to calculate positioning information, and the positioning modes include differential GNSS/IMU (Global navigation satellite system/Inertial measurement unit) combined positioning mode and GNSS/IMU combined positioning mode; when the slave communication verification terminal can receive complete differential information, the GNSS positioning system calculates the differential GNSS positioning information combined with the IMU, outputs and sends it to the base station; when the slave communication verification terminal cannot receive complete differential information, the GNSS positioning system and the IMU assisted positioning system calculate the GNSS positioning information combined with the IMU, output and send it to the base station.

GNSS positioning information is used as external input, and the IMU is frequently corrected during the movement of the mobile station to control the accumulation of its error over time, thereby further improving the accuracy of the acquired positioning information. When the mobile station still cannot obtain complete differential information after switching the communication mode, it is necessary to adopt a GNSS/IMU combined positioning mode with higher accuracy than the GNSS positioning mode to meet the accuracy requirements of the acquired positioning information. In addition, high-precision IMU-assisted positioning in a short period of time can effectively solve problems such as signal loss of lock, low refresh rate and cycle slip in GNSS dynamic environments.

Furthermore, step S6 includes the following steps:

S61. The mobile station makes the X1 axis and Y1 axis of the gyroscope parallel to the X2 axis and Y2 axis of the accelerometer respectively;

S62. Move the mobile station horizontally so that only the longitude and/or latitude of the positioning information changes. The X2 axis of the accelerometer corresponds to the positive direction of longitude, the Y2 axis corresponds to the positive direction of latitude, and the microcontroller sets the value corresponding to the Z axis of the gyroscope to 0°;

f为加速度计辅助刷新频率，t为GNSS定位信息的刷新时间间隔；S63. During the horizontal movement of the mobile station, the accelerometer measures the average acceleration A _X and A _Y in the time period Δt, and the gyroscope measures the change angle of the Z axis in the time period Δt.

f is the accelerometer auxiliary refresh frequency, and t is the refresh time interval of GNSS positioning information;

并计算出加速度在纬度单一变化方向和经度单一变化方向的投影向量

S64. The microcontroller records A _X , A _Y ,

And calculate the projection vector of acceleration in the single change direction of latitude and the single change direction of longitude

S65. Calculate the displacement of a single change in longitude according to the following formula:

The displacement in the direction of a single change in latitude is calculated using the following formula:

The V _lon and V _lat are respectively the ground speed in the longitude direction and the ground speed in the latitude direction of the last positioning result;

S66. The longitude and latitude of the last output positioning information are Lon1 and Lat2 respectively. After a period of time Δt, the longitude change ΔLon ₁ and latitude change ΔLat ₂ are inferred from the displacement of the accelerometer in each direction through the following formula:

计算得出新的经度

新的纬度

And according to

Calculate the new longitude

New latitude

和纬度地速

并返回步骤S64；S67. Calculate the longitude ground speed after the time period Δt according to the following formula

and latitude ground speed

And return to step S64;

的GNSS定位信息并发送至基准站，在GNSS系统定位刷新时刻输出GNSS定位信息并转发至基准站。S68. After a period of time Δt, the output is combined

The GNSS positioning information is sent to the base station, and the GNSS positioning information is output and forwarded to the base station at the GNSS system positioning refresh time.

纬度

在GNSS采样输出周期间隔t(默认1s)内辅助换算输出经度、纬度，提高定位信息输出刷新率。In the GNSS/IMU combined positioning mode, the microcontroller calculates the new longitude based on the longitude change ΔLon ₁ and latitude change ΔLat ₂ measured by the IMU within the time period Δt.

latitude

Assist in converting and outputting longitude and latitude within the GNSS sampling output period interval t (default 1s) to improve the refresh rate of positioning information output.

Furthermore, the step S2 comprises:

S21. The host communication verification terminal performs an XOR operation on the differential information and an initial value, and generates a verification code;

S22. Place the check code at the end of the differential information;

S23. Send the differential information with the check code at the end to several slave communication check terminals.

The host communication verification terminal sends the differential information and the verification code to the slave communication verification terminal so that the slave communication verification terminal verifies the integrity of the differential information.

Furthermore, step S3 includes the following steps:

S31. The slave communication verification terminal receives the differential information with a check code at the end, extracts the differential information of a fixed length, performs an XOR operation to obtain a check value, and compares it with the check code;

S32. If the check value is the same as the received check code, a confirmation message is sent to the host communication verification terminal, and the difference information except the check value is sent to the mobile station;

S33. If the check value is different from the received check code, the confirmation information and differential information are not sent. When the host communication verification terminal does not receive the confirmation information within N (N is 3 to 12) differential information update cycles (default 1s), the communication mode is switched. When the slave communication verification terminal does not receive the complete differential information within N (N is 3 to 12) differential information update cycles (default 1s), the communication mode is switched. The host communication verification terminal and the slave communication verification terminal are in the same communication mode when they are started.

The slave communication verification terminal calculates the verification value according to the received differential information, and compares whether the verification value is consistent with the received verification code. If they are consistent, the differential information is complete, otherwise the differential information is incomplete.

A multi-channel differential multi-mode satellite navigation and positioning device comprises a reference station, a host communication verification terminal, a plurality of slave communication verification terminals, and a plurality of mobile stations;

The reference station includes a differential information output interface and a positioning information input interface, the host communication verification terminal includes a host data transmission interface, a host verification controller, and a host communication module, the slave communication verification terminal includes a slave data transmission interface, a slave verification controller, and a slave communication module, and the mobile station includes a verification result input interface, a positioning information output interface, a confirmation module, and a positioning system;

The differential information output interface sends the differential information to the host data transmission interface;

The host data transmission interface receives the differential information sent by the differential information output interface, the host check controller generates a check code according to the differential information, and the host communication module sends the differential information and the check code to the slave communication module;

The slave communication module receives the differential information and the check code sent by the host communication module, the slave check controller performs integrity check of the differential information according to the differential information and the check code to obtain a check result, and the slave data transmission interface sends the check result to the check result input interface;

The verification result input interface receives the verification result sent by the slave data transmission interface, the confirmation module decides whether to send confirmation information to the host data transmission interface according to the verification result, the positioning system calculates the positioning information, and the positioning information output interface sends the positioning information to the positioning information input interface;

The host communication verification terminal is provided with a host communication module switching switch, and the slave communication verification terminal is provided with a slave communication module switching switch, the host communication module includes a host network communication module and a host radio station communication module, and the slave communication module includes a slave network communication module and a slave radio station communication module;

According to whether the host data transmission interface receives confirmation information, the host communication module block switch maintains the current host communication module or switches the host communication module, and the slave communication module switching switch maintains the current slave communication module or switches the slave communication module.

The host network communication module and the slave network communication module adopt the network communication mode; the host radio station communication module and the slave network communication module adopt the radio station communication mode. Different communication modes have both advantages and disadvantages and different applicability. The transmission distance of the radio station communication mode is limited; the network communication mode is unstable. Therefore, it is necessary to select a suitable communication mode in different scenarios. The host communication verification terminal can select the corresponding differential communication link under different communication modes according to the integrity verification result of the differential information to ensure the integrity of the differential information, thereby improving the positioning efficiency and positioning accuracy.

If the integrity check result shows that the differential information is complete, the confirmation module sends confirmation information to the host data transmission interface, and the host communication module switching switch and the slave communication module switching switch maintain the current host communication mode and slave communication mode; if the integrity check result shows that the differential information is incomplete, the confirmation module will not send confirmation information to the host data transmission interface, and the host communication module switching switch and the slave communication module switching switch will switch the host communication module and the slave communication module respectively.

The host communication mode is consistent with the slave communication mode to ensure effective communication connection between the host communication verification terminal and the slave communication verification terminal. When the host communication verification terminal switches the communication mode, the slave communication verification terminal also switches the communication mode.

The host communication verification terminal can send differential information and verification codes to multiple slave communication verification terminals, and the slave communication verification terminal can send verification results to multiple mobile stations, thereby realizing one-to-many concurrent differential information of the base station, which can reduce the investment in the base station and reduce the cost of the overall system.

Furthermore, the positioning system includes a GNSS positioning system and an IMU-assisted positioning system; when the slave communication verification terminal can receive complete differential information, the GNSS positioning system calculates differential GNSS positioning information combined with the IMU, outputs it and sends it to the base station; when the slave communication verification terminal cannot receive complete differential information, the GNSS positioning system and the IMU-assisted positioning system calculate GNSS positioning information combined with the IMU, outputs it and sends it to the base station.

The GNSS positioning information calculated by the GNSS system is used as external input, and the positioning information calculated by the IMU-assisted positioning system is frequently corrected during the movement of the mobile station to control the accumulation of its error over time, thereby further improving the accuracy of the acquired positioning information.

Further, the IMU-assisted positioning system includes a gyroscope, an accelerometer, and a microcontroller;

所述加速度计用于测量时间段Δt内移动站的平均加速度A_X、A_Y，

f为加速度计辅助刷新频率，t为GNSS定位信息的刷新时间间隔；The gyroscope is used to measure the change angle of the Z axis within the time period Δt

The accelerometer is used to measure the average acceleration A _X , A _Y of the mobile station within a time period Δt.

f is the accelerometer auxiliary refresh frequency, and t is the refresh time interval of GNSS positioning information;

并计算出新的经度

新的纬度

并经过时间段Δt后发送结合

的GNSS定位信息至基准站，其余时刻发送GNSS定位信息至基准站。The microcontroller is used to record A _X , A _Y ,

and calculate the new longitude

New latitude

After a period of time Δt, the combined

The GNSS positioning information is sent to the base station at the same time, and the GNSS positioning information is sent to the base station at the rest of the time.

The mobile station has built-in gyroscopes and accelerometers. In the GNSS/IMU combined positioning mode and the differential GNSS/IMU combined positioning mode, the gyroscope can determine the single longitude and latitude change angles, and the accelerometer can calculate the displacement changes in the longitude and latitude directions through integral calculation and in conjunction with the gyroscope, and assist in converting the output longitude and latitude within the GNSS sampling output cycle interval t, thereby improving the refresh rate of the positioning information output.

Furthermore, the mobile station is also provided with a barometer, which obtains air pressure information and altitude information and forwards them to the base station, the gyroscope obtains attitude information and angle information of the mobile station and forwards them to the base station, and the accelerometer obtains acceleration information of the mobile station and forwards it to the base station.

The mobile station can obtain more information besides positioning information, so that the staff at the base station can fully understand the status information of the mobile station.

Furthermore, the base station is provided with a display for displaying positioning information, attitude information, angle information, air pressure information, altitude information, and acceleration information.

The display installed at the base station allows staff to monitor the mobile station's positioning information, attitude information, angle information, air pressure information, altitude information, and acceleration information.

Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

(1) The multi-path differential multi-mode satellite navigation positioning method and device described in the present invention simultaneously supports mobile network communication and wireless radio station dual communication, and can adaptively switch according to the data quality of the differential information communication link to improve data reliability and positioning accuracy, thereby improving adaptability to various field operation applications.

(2) The mobile station and slave communication verification terminal can automatically identify and determine the complete validity of the differential signal, selectively use the appropriate differential communication link, and effectively improve the utilization rate of the baseline length.

(3) When the differential data is abnormal, the mobile station automatically switches between the GNSS/IMU combined positioning mode and the differential GNSS/IMU combined positioning mode, effectively improving the refresh rate of GNSS positioning information.

(4) The base station and mobile station can send differential signals one-to-many and the transmission distance will be greatly improved.

(5) The same base station can support multiple mobile stations at the same time and observe the status information of the mobile stations in real time. This is a great advantage in the application of one machine with multiple controls.

(6) The IMU-assisted positioning information output method is adopted. Regardless of the data quality of the differential information, the GNSS positioning information combined with the IMU positioning information is output, and the blank segment of the GNSS positioning information output data stream is filled, thereby obtaining a higher data update rate at a lower cost.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of a mobile station according to an embodiment of the present invention;

2 is a schematic diagram of a slave communication verification terminal according to an embodiment of the present invention;

3 is a schematic diagram of a host communication verification terminal according to an embodiment of the present invention;

FIG4 is a schematic diagram of a reference station according to an embodiment of the present invention;

Description 1. Verification result input interface; 2. Positioning information output interface; 3. Confirmation module; 4. Positioning system; 5. Mobile station multi-frequency active antenna; 6. Gyroscope; 7. Accelerometer; 8. Barometer; 9. Slave data transmission interface; 10. Slave verification controller; 11. Slave communication module; 12. Slave network antenna; 13. Slave radio station antenna; 14. Slave communication module switching switch; 15. Host data transmission interface; 16. Host verification controller; 17. Host communication module; 18. Host network antenna; 19. Host radio station antenna; 20. Host communication module switching switch; 21. Differential information output interface; 22. Positioning information input interface; 23. Base station multi-frequency active antenna; 24. Display.

DETAILED DESCRIPTION

The drawings are for illustrative purposes only and are not to be construed as limiting the present patent;

In order to better illustrate the present embodiment, some parts in the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product;

It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

Example

As shown in FIGS. 1 to 4 , a multi-path differential multi-mode satellite navigation positioning method is characterized in that it includes the following steps:

S1. The base station sends the differential information to the host communication verification terminal;

S2. The host communication verification terminal receives the differential information sent by the reference station, generates a verification code, and sends the differential information and the verification code to several slave communication verification terminals;

S3. The slave communication verification terminal receives the differential information and the check code sent by the host communication verification terminal, performs a check on the integrity of the differential information to obtain the check result, and sends the check result to several mobile stations;

S4. The mobile station decides whether to send a confirmation message to the host communication verification terminal based on the received verification result;

S5. The host communication verification terminal maintains the current communication mode or switches the communication mode according to whether the confirmation information is received, wherein the communication mode includes a network communication mode and a radio station communication mode;

S6. The mobile station calculates the positioning information output according to the differential information and sends it to the host communication verification terminal of the base station through the slave communication verification terminal. The base station can obtain the positioning information of the mobile station.

A variety of communication modes are integrated in the host communication verification terminal and the slave communication verification terminal, including the network communication mode and the radio station communication mode, so that the host communication verification terminal can select the corresponding differential communication link under different communication modes according to the integrity verification result of the differential information, thereby ensuring the integrity of the differential information and improving the positioning efficiency and positioning accuracy.

If the integrity check result shows that the differential information is complete, the mobile station sends a confirmation message to the host communication verification terminal, and the host communication verification terminal maintains the current communication mode; if the integrity check result shows that the differential information is incomplete, the mobile station does not send a confirmation message to the host communication verification terminal, and the host communication verification terminal switches the communication mode.

The communication mode adopted by the host communication verification terminal and the slave communication verification terminal is consistent to ensure effective communication connection between the host communication verification terminal and the slave communication verification terminal. When the host communication verification terminal switches the communication mode, the slave communication verification terminal also switches the communication mode.

The host communication verification terminal can send differential information and verification codes to multiple slave communication verification terminals, and the slave communication verification terminal can send verification results to multiple mobile stations, thereby realizing one-to-many concurrent differential information of the base station, which can reduce the investment in the base station and reduce the cost of the overall system.

Furthermore, the mobile station can select different positioning modes to calculate positioning information, and the positioning modes include differential GNSS/IMU combined positioning mode and GNSS/IMU combined positioning mode; when the slave communication verification terminal can receive complete differential information, the GNSS positioning system calculates the differential GNSS positioning information combined with the IMU, outputs and sends it to the base station; when the slave communication verification terminal cannot receive complete differential information, the GNSS positioning system and the IMU assisted positioning system calculate the GNSS positioning information combined with the IMU, output and send it to the base station.

GNSS positioning information is used as an external input, and the IMU is frequently corrected during the movement of the mobile station to control the accumulation of its error over time, thereby further improving the accuracy of the acquired positioning information. When the mobile station still cannot obtain complete differential information after switching the communication mode, it is necessary to adopt a GNSS/IMU combined positioning mode with higher accuracy than the GNSS positioning mode to meet the accuracy requirements of the acquired positioning information. In addition, high-precision IMU-assisted positioning in a short period of time can effectively solve problems such as signal loss of lock, low refresh rate and cycle slip in GNSS dynamic environments.

Furthermore, step S6 includes the following steps:

S61. The mobile station makes the X1 axis and Y1 axis of the gyroscope 6 parallel to the X2 axis and Y2 axis of the accelerometer 7, respectively;

S62. Horizontally move the mobile station so that the positioning information changes only in longitude and/or latitude. The X2 axis of the accelerometer 7 corresponds to the positive longitude direction, the Y2 axis corresponds to the positive latitude direction, and the microcontroller sets the value corresponding to the gyroscope 6Z axis to 0°;

f为加速度计7辅助刷新频率，t为GNSS定位信息的刷新时间间隔；S63. During the horizontal movement of the mobile station, the accelerometer 7 measures the average acceleration A _X and A _Y in the time period Δt, and the gyroscope 6 measures the change angle of the Z axis in the time period Δt.

f is the auxiliary refresh frequency of the accelerometer 7, and t is the refresh time interval of the GNSS positioning information;

并计算出加速度在纬度单一变化方向和经度单一变化方向的投影向量

S64. The microcontroller records A _X , A _Y ,

And calculate the projection vector of acceleration in the single change direction of latitude and the single change direction of longitude

S65. Calculate the displacement of a single change in longitude according to the following formula:

The displacement in the direction of a single change in latitude is calculated using the following formula:

The V _lon and V _lat are respectively the longitude ground speed and latitude ground speed of the last positioning result;

S66. The longitude and latitude of the last output positioning information are Lon1 and Lat2 respectively. After a period of time Δt, the longitude change ΔLon ₁ and latitude change ΔLat ₂ are inferred from the displacement of the accelerometer 7 in each direction by the following formula:

计算得出新的经度

新的纬度

And according to

Calculate the new longitude

New latitude

和纬度地速

并返回步骤S64；S67. Calculate the longitude ground speed after the time period Δt according to the following formula

and latitude ground speed

And return to step S64;

的GNSS定位信息至基准站，在GNSS系统定位刷新时刻输出GNSS定位信息并转发至基准站。S68. After a period of time Δt, send the combined

The GNSS positioning information is sent to the base station, and the GNSS positioning information is output and forwarded to the base station at the GNSS system positioning refresh time.

纬度

在GNSS采样输出周期间隔t内辅助换算输出经度、纬度，提高定位信息输出刷新率。In the GNSS/IMU combined positioning mode, the microcontroller calculates the new longitude based on the longitude change ΔLon ₁ and latitude change ΔLat ₂ measured by the IMU within the time period Δt.

latitude

Assist in converting and outputting longitude and latitude within the GNSS sampling output period interval t to improve the refresh rate of positioning information output.

Furthermore, the step S2 comprises:

S21. The host communication verification terminal performs an XOR operation on the differential information and an initial value, and generates a verification code;

S22. Place the check code at the end of the differential information;

S23. Send the differential information with the check code at the end to several slave communication check terminals.

The host communication terminal performs an XOR operation on each byte data _Ai of the differential information string A and '0' to obtain a set of new strings _Bi . First, the length of the differential information string A is obtained, which is recorded as length:

Perform a sum operation on _Bi to obtain a check value Sum_send:

Sum_send＝∑B _i ,i∈[0,length]

Sum_send is stored as a fixed 4-digit number and added to the end of the differential information string to form string C:

C = [A1, A2, A3…Sum_send]

Send the character string C to the slave communication verification terminal.

Furthermore, step S3 includes the following steps:

S31. The slave communication verification terminal receives the differential information with the check code at the end, and performs an XOR operation on the check code to obtain a check value;

S32. Compare the check code with the check value;

S33. Send the comparison result to several mobile stations.

The slave communication verification terminal will receive the string C and calculate the XOR sum verification value excluding the last 4 digits to obtain Sum_received. Sum_received is compared with Sum_send. If they are equal, the differential information string D excluding the last 4 digits is sent to the mobile station, and the confirmation code and mobile station status information are returned to the host communication verification terminal.

As shown in Fig. 1 to Fig. 4, a multi-channel differential multi-mode satellite navigation and positioning device is characterized in that it includes a reference station, a host communication verification terminal, a plurality of slave communication verification terminals, and a plurality of mobile stations;

The reference station includes a differential information output interface 21 and a positioning information input interface 22, the host communication verification terminal includes a host data transmission interface 15, a host verification controller 16, and a host communication module 17, the slave communication verification terminal includes a slave data transmission interface 9, a slave verification controller 10, and a slave communication module 11, and the mobile station includes a verification result input interface 1, a positioning information output interface 2, a confirmation module 3, and a positioning system 4;

The differential information output interface 21 sends the differential information to the host data transmission interface 15;

The host data transmission interface 15 receives the differential information sent by the differential information output interface 21, the host check controller 16 generates a check code according to the differential information, and the host communication module 17 sends the differential information and the check code to the slave communication module 11;

The slave communication module 11 receives the differential information and the check code sent by the host communication module 17, the slave check controller 10 performs integrity check of the differential information according to the differential information and the check code to obtain a check result, and the slave data transmission interface 9 sends the check result to the check result input interface 1;

The verification result input interface 1 receives the verification result sent by the slave data transmission interface 9, the confirmation module 3 decides whether to send confirmation information to the host data transmission interface 15 according to the verification result, the positioning system 4 calculates the positioning information, and the positioning information output interface 2 sends the positioning information to the positioning information input interface 22;

The host communication verification terminal is provided with a host communication module switching switch 20, the slave communication verification terminal is provided with a slave communication module switching switch 14, the host communication module 17 includes a host network communication module and a host radio station communication module, and the slave communication module 11 includes a slave network communication module and a slave radio station communication module;

According to whether the host data transmission interface 15 receives the confirmation information, the host communication module block switch 20 maintains the current host communication module 17 or switches the host communication module 17, and the slave communication module switching switch 14 maintains the current slave communication module 11 or switches the slave communication module 11.

The differential information output interface 21 is electrically connected to the host data transmission interface 15, the host communication module 17 is electrically connected to the slave communication module 11, the slave data transmission interface 9 is electrically connected to the verification result input interface 1, the confirmation module 3 is electrically connected to the host data transmission interface 15, and the positioning information output interface 2 is electrically connected to the positioning information input interface 22.

The host network communication module and the slave network communication module adopt the network communication mode; the host radio station communication module and the slave network communication module adopt the radio station communication mode. Different communication modes have both advantages and disadvantages and different applicability. The transmission distance of the radio station communication mode is limited; the network communication mode is unstable. Therefore, it is necessary to select a suitable communication mode in different scenarios. The host communication verification terminal can select the corresponding differential communication link under different communication modes according to the integrity verification result of the differential information to ensure the integrity of the differential information, thereby improving the positioning efficiency and positioning accuracy.

If the integrity check result shows that the differential information is complete, the confirmation module 3 sends the confirmation information to the host data transmission interface 15, and the host communication module switching switch 20 and the slave communication module switching switch 14 maintain the current host communication mode and slave communication mode; if the integrity check result shows that the differential information is incomplete, the confirmation module 3 will not send the confirmation information to the host data transmission interface 15, and the host communication module switching switch 20 and the slave communication module switching switch 14 will switch the host communication module 17 and the slave communication module 11 respectively.

The host communication mode is consistent with the slave communication mode to ensure effective communication connection between the host communication verification terminal and the slave communication verification terminal. When the host communication verification terminal switches the communication mode, the slave communication verification terminal also switches the communication mode.

In this embodiment, the host network communication module and the slave network communication module are respectively provided with a host network antenna 18 and a slave network antenna 12; the host radio station communication module and the slave radio station communication module are respectively provided with a host radio station antenna 19 and a slave radio station antenna 13, which enhances the communication between the slave communication verification terminal and the host communication verification terminal.

In this embodiment, the base station is provided with a base station multi-frequency active antenna 23, and the mobile station is provided with a mobile station multi-frequency active antenna 5, which can enhance the communication between the base station and the host communication verification terminal, the mobile station and the slave communication verification terminal, and the base station and the mobile station.

The host communication verification terminal can send differential information and verification codes to multiple slave communication verification terminals, and the slave communication verification terminal can send verification results to multiple mobile stations, thereby realizing one-to-many concurrent differential information of the base station, which can reduce the investment in the base station and reduce the cost of the overall system.

Furthermore, the positioning system 4 includes a GNSS positioning system and an IMU-assisted positioning system;

The GNSS positioning information calculated by the GNSS system is used as an external input. During the movement of the mobile station, the positioning information calculated by the IMU-assisted positioning system is frequently corrected to control the accumulation of errors over time, thereby further improving the accuracy of the acquired positioning information. When the slave communication verification terminal can obtain complete differential information, the differential GNSS positioning information combined with the IMU is calculated; when the host communication verification terminal still cannot obtain complete differential information after switching the host communication module and the slave communication module, it is necessary to use the GNSS system and the IMU-assisted positioning system to calculate the GNSS positioning information combined with the IMU to improve the accuracy of the positioning information.

Further, the IMU-assisted positioning system includes a gyroscope 6, an accelerometer 7, and a microcontroller;

所述加速度计7用于测量时间段Δt内移动站的平均加速度A_X、A_Y，

f为加速度计7辅助刷新频率，t为GNSS定位信息的刷新时间间隔；The gyroscope 6 is used to measure the change angle of the Z axis within the time period Δt

The accelerometer 7 is used to measure the average acceleration A _X , A _Y of the mobile station within a time period Δt.

f is the auxiliary refresh frequency of the accelerometer 7, and t is the refresh time interval of the GNSS positioning information;

并计算出新的经度

新的纬度

并经过时间段Δt后发送结合

的GNSS定位信息至基准站，其余时刻发送GNSS定位信息至基准站。The microcontroller is used to record A _X , A _Y ,

and calculate the new longitude

New latitude

After a period of time Δt, the combined

The GNSS positioning information is sent to the base station at the same time, and the GNSS positioning information is sent to the base station at the rest of the time.

The mobile station has a built-in gyroscope 6 and an accelerometer 7. In the GNSS/IMU combined positioning mode or the differential GNSS/IMU combined positioning mode, the gyroscope 6 can determine a single longitude and latitude change angle, and the accelerometer 7 can calculate the displacement changes in the longitude and latitude directions through integral calculation and in cooperation with the gyroscope 6, and assist in converting and outputting the longitude and latitude within the GNSS sampling output cycle interval t, thereby improving the refresh rate of the positioning information output.

Furthermore, the mobile station is also provided with a barometer, which obtains air pressure information and altitude information and forwards them to the base station, the gyroscope 6 obtains attitude information and angle information of the mobile station and forwards them to the base station, and the accelerometer 7 obtains acceleration information of the mobile station and forwards it to the base station.

The mobile station can obtain more information besides positioning information, so that the staff at the base station can fully understand the status information of the mobile station.

Furthermore, the base station is provided with a display 24 for displaying the positioning information, attitude information, angle information, air pressure information, altitude information, and acceleration information of the mobile station.

The display 24 provided at the base station facilitates the staff to monitor the positioning information, attitude information, angle information, air pressure information, altitude information, and acceleration information of the mobile station.

The same or similar reference numerals correspond to the same or similar components;

The positional relationships described in the drawings are only for illustrative purposes and should not be construed as limiting the present patent.

Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims (8)

1. The multipath differential multimode satellite navigation positioning method is characterized by comprising the following steps of:

s1, a reference station sends differential information to a host communication verification terminal;

s2, the host communication check terminal receives the differential information sent by the reference station, generates a check code, and sends the differential information and the check code to a plurality of slave communication check terminals;

S3, the slave communication check terminal receives the differential information and the check code sent by the host communication check terminal, performs integrity check on the differential information to obtain a check result, and sends the check result to the mobile station;

s4, the mobile station decides whether to send the confirmation information to the host communication check terminal according to the received check result;

s5, the host communication verification terminal keeps a current communication mode or switches the communication mode according to whether acknowledgement information is received, wherein the communication mode comprises a network communication mode and a radio station communication mode;

s6, the mobile station calculates positioning information according to the differential information, outputs the positioning information, and forwards the positioning information to a host communication check terminal of the reference station through a slave communication check terminal, and the reference station acquires the positioning information of the mobile station through the host communication check terminal;

the mobile station can select different positioning modes to calculate positioning information, wherein the positioning modes comprise a differential GNSS/IMU combined positioning mode and a GNSS/IMU combined positioning mode;

when the slave communication verification terminal can receive complete differential information, the mobile station selects a differential GNSS/IMU combined positioning mode, outputs differential GNSS positioning information combined with the IMU positioning information and sends the differential GNSS positioning information to the reference station; when the slave communication verification terminal cannot receive complete differential information, the mobile station selects a GNSS/IMU combined positioning mode, outputs GNSS positioning information combined with the IMU positioning information and sends the GNSS positioning information to the reference station;

The step S6 includes the steps of:

s61, the mobile station respectively parallels an X1 axis and a Y1 axis of the gyroscope with an X2 axis and a Y2 axis of the accelerometer;

s62, horizontally moving the mobile station to enable the positioning information to change only in longitude and/or latitude, enabling an X2 axis of the accelerometer to correspond to the longitude positive direction, enabling a Y2 axis to correspond to the latitude positive direction, and enabling a microcontroller to set a value corresponding to a Z axis of the gyroscope to be 0 degrees;

s63, in the horizontal movement process of the mobile station, the accelerometer measures the average acceleration A in the time period delta t _X 、A _Y The gyroscope measures the change angle of the Z axis in the time period delta t

f is the auxiliary refresh frequency of the accelerometer, and t is the refresh time interval of the GNSS positioning information;

s64 microcontroller records A _X 、A _Y 、

And calculate the projection vector of acceleration in the latitude single change direction and longitude single change direction +.>

S65, calculating displacement of the single-change longitudinal movement direction according to the following formula,

the displacement in the direction of movement of the single change in latitude is calculated according to the following,

the V is _lon 、V _lat The longitudinal ground speed and the latitudinal ground speed of the last positioning result are respectively;

s66, the longitude and latitude of the last output positioning information are Lon1 and Lat2 respectively, and after the time period delta t, the longitude change delta Lon is reversely pushed according to the displacement of the accelerometer in each direction ₁ Latitude variation ΔLat ₂ ，

And according to

Calculating to obtain new longitude->

New latitude

S67, calculating the longitude ground speed after the time period delta t according to the following formula

And latitude ground speed->

And returns to step S64;

s68, after the time period delta t, outputting the combination

And transmitting the GNSS positioning information to the reference station, and outputting the GNSS positioning information at the GNSS system positioning refreshing time and forwarding the GNSS positioning information to the reference station.

2. The multi-channel differential multimode satellite navigation positioning method according to claim 1, wherein the step S2 comprises:

s21, the host communication verification terminal performs exclusive OR operation on the differential information and an initial value once, and generates a verification code;

s22, placing a check code at the tail part of the differential information;

s23, differential information with check codes at the tail parts is sent to a plurality of slave communication check terminals.

3. The multi-channel differential multimode satellite navigation positioning method according to claim 2, wherein the step S3 comprises the steps of:

s31, the slave communication verification terminal receives differential information with the verification code at the tail, extracts the differential information with the fixed length, performs exclusive or and sum operation to obtain a verification value, and compares the verification value with the verification code;

s32, if the check value is the same as the received check code, sending confirmation information to the host communication check terminal, and sending differential information without the check value to the mobile station;

S33, if the check value is different from the received check code, no confirmation information and no difference information are sent; the host communication verification terminal switches the communication mode when the confirmation information is not received in N differential information updating periods; the slave communication verification terminal switches the communication mode when the complete differential information is not received in N differential information updating periods; the master communication check terminal and the slave communication check terminal are in the same communication mode when started.

4. A multi-path differential multimode satellite navigation positioning device applying the multi-path differential multimode satellite navigation positioning method according to any one of claims 1 to 3, which is characterized by comprising a reference station, a master communication check terminal, a plurality of slave communication check terminals and a plurality of mobile stations;

the reference station comprises a differential information output interface (21) and a positioning information input interface (22), the host communication check terminal comprises a host data transmission interface (15), a host check controller (16) and a host communication module (17), the slave communication check terminal comprises a slave data transmission interface (9), a slave check controller (10) and a slave communication module (11), and the mobile station comprises a check result input interface (1), a positioning information output interface (2), a confirmation module (3) and a positioning system (4);

The differential information output interface (21) sends differential information to the host data transmission interface (15);

the host data transmission interface (15) receives the differential information sent by the differential information output interface (21), the host verification controller (16) generates a verification code according to the differential information, and the host communication module (17) sends the differential information and the verification code to the slave communication module (11);

the slave communication module (11) receives the differential information and the check code sent by the host communication module (17), the slave check controller (10) performs integrity check of the differential information according to the differential information and the check code to obtain a check result, and the slave data transmission interface (9) sends the check result to the check result input interface (1);

the verification result input interface (1) receives the verification result sent by the slave data transmission interface (9), the confirmation module (3) determines whether to send confirmation information to the host data transmission interface (15) according to the verification result, the positioning system (4) calculates positioning information, and the positioning information output interface (2) sends the positioning information to the positioning information input interface (22);

the host communication verification terminal is provided with a host communication module change-over switch (20), the slave communication verification terminal is provided with a slave communication module change-over switch (14), the host communication module (17) comprises a host network communication module and a host radio station communication module, and the slave communication module (11) comprises a slave network communication module and a slave radio station communication module;

According to whether the host data transmission interface (15) receives the confirmation information, the host communication module cut switch (20) keeps the current host communication module (17) or switches the host communication module (17), and the slave communication module switch (14) keeps the current slave communication module (11) or switches the slave communication module (11).

5. The multi-channel differential multimode satellite navigation positioning device of claim 4, wherein the positioning system (4) comprises a GNSS positioning system, an IMU assisted positioning system;

when the slave communication verification terminal can receive complete differential information, the GNSS positioning system calculates differential GNSS positioning information combined with the IMU, outputs and sends the differential GNSS positioning information to the reference station; when the slave communication verification terminal can not receive complete differential information, the GNSS positioning system and the IMU auxiliary positioning system calculate GNSS positioning information combined with the IMU, output the GNSS positioning information and send the GNSS positioning information to the reference station.

6. The multi-channel differential multimode satellite navigation positioning device of claim 5, wherein the IMU assisted positioning system comprises a gyroscope (6), an accelerometer (7), a microcontroller;

the gyroscope (6) is used for measuring the change angle of the Z axis in the time period delta t

The accelerometer (7) is used for measuring the average acceleration A of the mobile station in a time period delta t _X 、A _Y ，

f is the auxiliary refresh frequency of the accelerometer, and t is the refresh time interval of the GNSS positioning information;

the microcontroller is used for recording A _X 、A _Y 、

And calculates a new longitude +>

New latitude->

And outputting the combination +.after the time period delta t>

And forwarding the GNSS positioning information to the reference station, and outputting the GNSS positioning information at the GNSS system positioning refreshing time and forwarding the GNSS positioning information to the reference station.

7. The multi-path differential multimode satellite navigation positioning device according to claim 6, wherein the mobile station is further provided with a barometer, the barometer acquires barometer information, altitude information and forwards the barometer information to a reference station, the gyroscope (6) acquires attitude information, angle information and forwards the mobile station to the reference station, and the accelerometer (7) acquires acceleration information of the mobile station and forwards the mobile station to the reference station.

8. The multi-channel differential multimode satellite navigation positioning device of claim 7, wherein the reference station is provided with a display (24) for displaying positioning information, attitude information, angle information, barometric pressure information, altitude information, acceleration information of the mobile station.

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