Low-power sub-meter communication navigation and positioning device and method based on narrowband Internet of Things

Abstract

Disclosed is a low-power sub-meter communication navigation positioning device and method based on narrowband Internet of Things, which can achieve high-precision positioning at the sub-meter level in complex environments. The device includes a sub-meter positioning system, a cloud server, and a GNSS base station. The sub-meter positioning system includes a microprocessing unit, and a GNSS module and an NB‑IoT module connected to the microprocessing unit. The GNSS module receives satellite navigation data, and the NB‑IoT module obtains error correction data measured by the GNSS base station from the cloud server. The microprocessing unit calls a deep-tight combined pseudo-range phase adaptive differential positioning technology algorithm to process the satellite navigation data received by the GNSS module and the base station correction data received by the NB‑IoT module to obtain a high-precision positioning result. The NB‑IoT module sends the positioning result to the cloud server, so that the user can view the positioning result not only on his own device, but also on other terminals.

Description

Technical Field

[0001] The present disclosure relates to a low-power sub-meter communication navigation and positioning device and method based on narrowband Internet of Things. Background Art

[0002] At present, outdoor positioning mainly relies on the Global Navigation Satellite System (GNSS), and users achieve positioning by receiving satellite signals. However, GNSS satellite signals are easily affected by the external environment. The multipath effect is obvious in urban canyons, forests, and mountain canyons. At the same time, in places without signals such as tunnels and underground passages, the navigation and positioning results of the navigation equipment currently on the market will be greatly deviated or even unable to be positioned, which greatly limits the scope of use of navigation equipment. Summary of the invention

[0003] The present invention provides a low-power sub-meter communication navigation and positioning device based on narrowband Internet of Things. The navigation and positioning system and the communication system are integrated together to achieve high-precision and reliable remote real-time positioning, especially in complex environments, to achieve sub-meter positioning results.

[0004] At least one embodiment of the present disclosure provides a communication navigation positioning device, including a sub-meter positioning system, wherein the sub-meter positioning system includes:

[0005] Microprocessing unit;

[0006] a GNSS module, configured to receive satellite navigation data and send the processed satellite navigation data to the microprocessor unit; and

[0007] The NB-IoT module is used to receive error correction data measured by the GNSS base station and send the error correction data to the microprocessor unit;

[0008] The microprocessing unit processes the satellite navigation data received by the GNSS module and the base station correction data received by the NB-IoT module according to a tightly combined pseudo-range phase adaptive differential positioning technology algorithm to obtain a positioning result, and the NB-IoT module sends the positioning result.

[0009] In some examples, the NB-IoT module receives the error correction data from a cloud server.

[0010] In some examples, the NB-IoT module sends the positioning results to a cloud server.

[0011] In some examples, the microprocessing unit communicates with the NB-IoT module and the GNSS module via a serial port.

[0012] At least one embodiment of the present disclosure provides a communication navigation positioning method, including:

[0013] The GNSS module receives satellite observation data, processes the received satellite observation data and sends it to the microprocessor unit;

[0014] The NB-IoT module receives error correction data measured by the GNSS base station and sends the error correction data to the microprocessor unit;

[0015] The microprocessing unit processes the satellite navigation data received by the GNSS module and the base station correction data received by the NB-IoT module according to a deep and tight combined pseudo-range phase adaptive differential positioning technology algorithm to obtain a positioning result;

[0016] The NB-IoT module sends the positioning result.

[0017] In some examples, the NB-IoT module obtains the error correction data measured by the GNSS base station from a cloud server.

[0018] In some examples, the NB-IoT module sends the positioning results to a cloud server for storage. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the embodiment of the present disclosure, the drawings of the embodiment are briefly introduced below.

[0020] Figure 1 This is a block diagram of a low-power sub-meter communication navigation and positioning device based on narrowband Internet of Things.

[0021] Figure 2 This is the internal block diagram of the NB-IoT module in the sub-meter positioning system.

[0022] Figure 3 This is the internal block diagram of the microprocessor unit (MCU) module in the sub-meter positioning system.

[0023] Figure 4 This is the internal block diagram of the GNSS module in the sub-meter positioning system.

[0024] Figure 5 This is the connection diagram of the internal modules in the sub-meter positioning system.

[0025] Figure 6 This paper introduces the deep and tight combined pseudo-range phase adaptive differential positioning technology. DETAILED DESCRIPTION

[0026] A low-power sub-meter communication navigation and positioning device based on narrowband Internet of Things includes a GNSS base station, a terminal, a cloud server, and a sub-meter positioning system. The sub-meter positioning system includes a microprocessor unit (MCU), a GNSS module, and a NB-IoT module. Figure 1 As shown, the GNSS base station searches for GNSS signals and obtains the data observed by the GNSS base station. In addition, since the three-dimensional coordinates of the GNSS base station are fixed and known, the GNSS base station can use the precise reference coordinates to obtain the error of the base station observation data. The error can be a pseudo-range correction or a position correction. The GNSS base station sends the base station observation data (error correction data) to the cloud server, and the cloud server sends the GNSS base station observation data to the sub-meter positioning system through wireless communication. In this disclosure, in order to solve the service needs of a large number of users at the same time, the cloud server adopts the MQTT Internet of Things communication protocol. GPS / Beidou satellites can also send satellite signals to the GNSS module in the sub-meter positioning system. Although the original observation data of GPS / Beidou can measure the distance from the satellite to the terminal, due to the influence of factors such as ionosphere and fading, the results measured by the original observation data of GPS / Beidou have a large error with the actual position result. The sub-meter positioning system receives the original observation data of GPS / Beidou through the GNSS module inside the system, and the MCU uses the received base station observation data and the original observation data of GPS / Beidou to perform differential calculation to obtain high-precision positioning results. The NB-IoT module then sends the positioning results to the cloud server, allowing users to view the positioning results not only on their own devices, but also on other terminals.

[0027] The sub-meter positioning system in this low-power sub-meter communication navigation and positioning device is implemented on an ARM-based embedded development platform. The ARM-based embedded development platform has stable performance, is easy to debug and communicate, and can achieve collaborative processing between platforms. The MCU using the Cortex-M7 core can simultaneously receive and process the original observation data sent by the GNSS module supporting Beidou / GPS and the base station correction data sent by the GNSS base station, and obtain sub-meter positioning results using the pseudo-range phase adaptive differential positioning algorithm based on deep tight combination.

[0028] Narrow Band Internet of Things (NB-IoT) is a major component of the Internet of Things and was defined by the 3rd Generation Partnership Project (3GPP) in the Rel-13 version released in 2016. Compared with the Cat-M1 protocol, NB-IoT consumes a narrower bandwidth and covers a longer distance, consuming only about 180KHz of bandwidth. Because the NB-IoT module has the advantages of low power consumption and insensitivity to latency, in order to make the communication navigation and positioning device better achieve low power consumption indicators as a whole, the NB-IoT module is used to send the differential positioning results processed by the MCU from the sub-meter positioning system to the cloud server, and the positioning device is powered by a unified system power management circuit to effectively regulate system energy consumption.

[0029] Compared with traditional servers, cloud servers (Elastic Compute Service, ECS) are simpler and more efficient to manage than physical servers. They can be elastically scaled in terms of processing power, reducing the difficulty of development and operation and overall IT costs. Users can quickly create or release any number of cloud servers without having to purchase hardware in advance.

[0030] Figure 2 The internal block diagram of the NB-IoT module in the sub-meter positioning system is shown. Figure 2 As shown, the NB-IoT module includes a processor submodule, a peripheral submodule, a communication submodule, and a power management circuit. The processor submodule includes a central processing unit (CPU), a cache memory, a static random access memory, and a non-volatile FLASH. The peripheral submodule includes a general I / O port, an I2C interface, a serial port, and a USIM interface. The communication submodule includes a modem, a random access memory, and a FLASH.

[0031] Figure 3 The internal block diagram of the microprocessor unit (MCU) module in the sub-meter positioning system is shown. Figure 3 As shown, the central processor of the MCU module uses the Cortex-M7 core. The central processor is connected to the bus matrix through the DCODE bus and the system bus, and is connected to the flash memory through the ICODE bus. The bus matrix is ​​equipped with static random access memory, reset and clock control circuits, USB, AHB bus, and direct memory access controller (DMA). The AHB bus connects two APB system buses in a bridging manner. The general I / O ports, serial ports, analog-to-digital converters, timers and other peripherals on the APB system bus are connected to the system bus through the bus matrix, allowing DMA access.

[0032] Figure 4The internal block diagram of the GNSS module in the sub-meter positioning system is shown. Figure 4 As shown in the figure, the GNSS module includes a radio frequency front end, an AD conversion chip, a GNSS baseband engine, a low noise amplifier, an antenna state detection and short circuit protection circuit, a central processing unit, a random access memory, FLASH, a real-time clock circuit, a power management circuit, a general I / O port, I2C, and a serial port. The antenna of the GNSS module can receive satellite data from Beidou or GPS. In order to better receive satellite signals, the antenna interface uses an active antenna. The antenna state detection and short circuit protection circuit integrated in the module can power the antenna more safely. The navigation data sent by GPS / Beidou is first processed by the GPS / Beidou radio frequency front end in the GNSS module, and then the analog intermediate frequency signal is converted into a digital intermediate frequency signal by the AD conversion chip, and then sent to the MCU through the serial port after being processed by the GNSS baseband engine.

[0033] Figure 5 The following figure shows the connection diagram of each module in the sub-meter positioning system. Figure 5 As shown, the MCU and the NB-IoT module communicate with each other through a serial port, and the MCU outputs the positioning result through an I2C interface or an I / O port. The USIM port on the NB-IoT module is used to connect the USIM chip. The NB-IoT module sends the positioning result processed by the MCU to the cloud server through wireless communication. The specific connection method of the MCU, GNSS module, and NB-IoT module is as follows: the sending end of the serial port on the GNSS module is connected to the receiving end of the MCU serial port 1, the GNSS module sends the original satellite observation data from the sending end of the serial port to the receiving end of the MCU serial port 1, and the receiving end of the serial port on the GNSS module is connected to the sending end of the MCU serial port 1; the sending end of the MCU serial port 2 is connected to the receiving end of the NB-IoT module serial port, the sending end of the MCU serial port 2 sends the positioning result obtained by the PPADA algorithm to the receiving end of the NB-IoT module serial port, the receiving end of the MCU serial port 2 is connected to the sending end of the NB-IoT module serial port, and the MCU uses the receiving end of the serial port 2 to receive the correction data of the base station.

[0034] In order to achieve sub-meter positioning in complex scenarios, the present disclosure adopts a tightly combined pseudo-range phase adaptive differential positioning technology. Figure 6As shown in the figure, this differential positioning technology can achieve positioning effects with different positioning accuracies. When the carrier phase observation or corresponding enhancement information is lost, the pseudo-range differential technology can achieve a positioning accuracy of 1-2 meters; when the carrier phase observation and the corresponding enhancement information are obtained, the sub-meter positioning accuracy can be achieved by calculating the ambiguity floating point solution differential positioning result; on this basis, if the ambiguity can be further corrected and effectively fixed, the positioning accuracy of 5 cm can be achieved. In an open environment, the three-difference solution information is used for cycle slip detection to obtain centimeter-level position change information between epochs and fix the ambiguity. In complex scenarios, the deep combination of GNSS and low-cost MEMS inertial navigation is used to improve the quality of satellite observation data and reduce the loss rate of carrier phase observations. In scenarios where GNSS signals are frequently interrupted, the GNSS / MEMS inertial navigation tight combination technology is used to obtain decimeter-level carrier relative position change information and improve the ambiguity re-convergence speed and reliability.

[0035] The working process of the above-mentioned low-power sub-meter communication navigation and positioning device based on narrowband Internet of Things includes receiving process, data processing process and sending process:

[0036] Receiving process: When a user needs positioning service, the positioning device is initialized and GNSS satellite signals are searched. The GNSS module of the sub-meter positioning system receives the original satellite observation data sent by the GPS / Beidou navigation satellite, and processes the received original GNSS satellite observation data and sends it to the MCU. The GNSS base station sends the base station correction data to the cloud server through its own GNSS device, and then the cloud server sends the correction data measured by the base station to the sub-meter positioning system through wireless communication. When the NB-IoT module of the sub-meter positioning system receives the base station correction data, it sends the data to the receiving end of the serial port of the MCU through the sending end of the serial port on the module.

[0037] Data processing process: After the MCU in the sub-meter positioning system uses two serial ports to receive the original GNSS observation data sent by the GNSS module serial port and the base station correction data sent by the NB-IoT module, the MCU uses a pseudo-range phase adaptive differential positioning algorithm based on deep tight combination to process the received data, and performs differential decomposition to obtain sub-meter positioning results in complex environments.

[0038] Sending process: The MCU of the sub-meter positioning system sends the positioning result obtained based on the deep and tight combined pseudo-range phase adaptive differential positioning technology algorithm to the NB-IoT module through the serial port. The NB-IoT module sends the differential positioning result to the cloud server through the antenna on the module. The positioning result is saved on the server and can be viewed by the terminal at any time.

Claims

1. A communication navigation positioning device, It is characterized in that A sub-meter positioning system is included, wherein the sub-meter positioning system includes: Microprocessing unit; a GNSS module, configured to receive satellite navigation data and send the processed satellite navigation data to the microprocessing unit; and The NB-IoT module is used to receive error correction data measured by the GNSS base station from the cloud server and send the error correction data to the microprocessing unit; The microprocessing unit processes the satellite navigation data received by the GNSS module and the error correction data received by the NB-IoT module according to a tightly combined pseudo-range phase adaptive differential positioning technology algorithm to obtain a positioning result, and the NB-IoT module sends the positioning result to the cloud server. The deep and tight combined pseudo-range phase adaptive differential positioning technology algorithm includes: When the carrier phase observation or corresponding enhancement information is lost, pseudo-range differential technology is used to achieve positioning with an accuracy of 1-2 meters; When obtaining carrier phase observations and corresponding enhancement information, the differential positioning results of the ambiguity floating-point solution are calculated to achieve sub-meter precision positioning. On this basis, the ambiguity is further correctly and effectively fixed to achieve centimeter-level precision positioning. Among them, in open environments, the three-difference solution information is used for cycle slip detection to obtain centimeter-level position change information between epochs, and the ambiguity is fixed. In complex scenarios, the deep combination of GNSS and MEMS inertial navigation is first used to improve the quality of satellite observation data and reduce the loss rate of carrier phase observations. The three-difference solution information is then used for cycle slip detection to obtain centimeter-level position change information between epochs, and the ambiguity is fixed.

2. The communication navigation positioning device according to claim 1, It is characterized in that The microprocessing unit communicates with the NB-IoT module and the GNSS module via a serial port.

3. A communication navigation positioning method, It is characterized in that include: The GNSS module receives satellite observation data, processes the received satellite observation data and sends it to the microprocessing unit; The NB-IoT module receives error correction data measured by the GNSS base station from the cloud server, and sends the error correction data to the microprocessing unit; The microprocessing unit processes the satellite observation data received by the GNSS module and the error correction data received by the NB-IoT module according to the deep and tight combined pseudo-range phase adaptive differential positioning technology algorithm to obtain a positioning result; The NB-IoT module sends the positioning result to the cloud server, The deep and tight combined pseudo-range phase adaptive differential positioning technology algorithm includes: When the carrier phase observation or corresponding enhancement information is lost, pseudo-range differential technology is used to achieve positioning with an accuracy of 1-2 meters; When obtaining carrier phase observations and corresponding enhancement information, the differential positioning results of the ambiguity floating-point solution are calculated to achieve sub-meter precision positioning. On this basis, the ambiguity is further correctly and effectively fixed to achieve centimeter-level precision positioning. Among them, in open environments, the three-difference solution information is used for cycle slip detection to obtain centimeter-level position change information between epochs, and the ambiguity is fixed. In complex scenarios, the deep combination of GNSS and MEMS inertial navigation is first used to improve the quality of satellite observation data and reduce the loss rate of carrier phase observations. The three-difference solution information is then used for cycle slip detection to obtain centimeter-level position change information between epochs, and the ambiguity is fixed.

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