Adaptive low-power 4G dual-mode positioning terminal

Abstract

The application discloses a self-adaptive low-power-consumption 4G dual-mode positioning terminal and relates to the technical field of Internet of Things positioning. In view of the problems of the existing positioning terminal, such as power consumption control dependence on the cloud, poor charging and discharging safety, low integration degree and the like, the application provides a terminal architecture integrating motion detection, positioning communication, power management and a main control module.A main control module outputs a motion or static state signal according to a motion detection module, and dynamically switches the working mode of a positioning communication module; meanwhile, a lithium battery protection chip is used to collect battery parameters in real time, and the main control controls a charging management chip to dynamically adapt to the charging mode according to the parameters, and immediately cuts off the load power supply when an abnormality is detected.The application realizes the unification of local autonomous motion sensing and hardware-level charging and discharging safety control, significantly prolongs the endurance time, guarantees the safety of equipment, and is suitable for vehicle positioning, logistics tracking and other Internet of Things scenes.

Description

Technical Field

[0001] This invention discloses an adaptive low-power 4G dual-mode positioning terminal, which relates to the fields of positioning and Internet of Things communication technology. Background Technology

[0002] With the development of IoT technology, 4G dual-mode positioning terminals are widely used in scenarios such as vehicle positioning, logistics tracking, and asset monitoring. These terminals are usually powered by batteries and need to operate for a long time in environments where the state of movement and stillness frequently switches. They have high requirements for positioning accuracy and battery life.

[0003] Regarding power consumption management, existing technologies include solutions based on switching operating modes according to motion state. For example, an accelerometer can be used to determine whether the terminal is in motion or stationary, and the positioning module can be powered off or the positioning frequency can be reduced when the terminal is stationary to save power. However, in such solutions, the motion detection function also stops or reduces its sensitivity after the terminal enters the stationary power-saving mode. Subsequently, it is necessary to rely on the main control to wake up periodically or the software to poll to re-detect the motion state. This method has a large response delay, and the periodic wake-up itself consumes additional power.

[0004] For example, Chinese patent application CN117241353A discloses a positioning terminal control method and system, which uses a triaxial accelerometer to determine the terminal's motion or stationary state and switches to different power consumption modes based on the operating state. This solution puts the CPU to sleep and shuts off the positioning module's power supply when the terminal is stationary, but the radio frequency module still needs to maintain a network connection for periodic paging. Furthermore, the re-detection of motion still relies on periodically waking the CPU for judgment, resulting in a significant response delay. In addition, when the positioning module's power supply is turned off, its power path remains connected, leading to static leakage current in the subsequent circuitry. This prevents purely hardware-level autonomous wake-up and still results in insufficient power saving and response speed in the lowest power consumption mode.

[0005] Regarding charge / discharge protection, existing technologies include solutions that trigger hardware switches to disconnect the load via voltage detection. These solutions employ independent hardware protection circuits that automatically disconnect the load when the battery voltage exceeds a fixed threshold. However, this approach has drawbacks: the protection threshold is fixed and cannot be adjusted, and the protection circuit and power management circuit operate independently. Even when the terminal is in a low-power sleep state, the protection circuit remains in full-power standby mode. Furthermore, the two circuits have independent power disconnection paths, increasing hardware costs and system complexity.

[0006] In summary, existing positioning terminals present a contradiction between power saving at rest and motion response, and lack coordination between power consumption control and safety protection. The shortcomings of these two aspects are superimposed, limiting further improvements in battery life and user experience. Summary of the Invention

[0007] To address the aforementioned problems, this invention discloses an adaptive low-power 4G dual-mode positioning terminal, which can achieve local autonomous motion sensing and dynamic power consumption adjustment, solving the problems of existing power control relying on the cloud, poor local autonomy, and failure when the network is down. It can construct a hardware-level charging and discharging collaborative safety architecture, monitor battery parameters in real time and automatically protect them, solving the problems of poor charging and discharging safety and easy damage to components in existing terminals. It can simultaneously achieve 4G communication and GNSS high-precision positioning through a highly integrated main control, solving the problems of low integration and unbalanced performance, forming an integrated terminal system of "4G communication + high-precision positioning + local adaptive low power consumption + charging and discharging safety".

[0008] To achieve the above objectives, the present invention provides an adaptive low-power 4G dual-mode positioning terminal. The terminal is integrated on a substrate and includes: a motion detection module integrated on the substrate for real-time acquisition of the terminal's acceleration data and outputting motion or stationary signals based on the acceleration data; a positioning communication module for acquiring the terminal's location data and transmitting it; a power supply module for supplying power to the various modules of the terminal, including a charging management chip, a lithium battery protection chip, a boost chip, and a buck regulator chip, wherein the boost chip has an enable pin and the buck regulator chip outputs an independent standby power supply; and a main control module electrically connected to the motion detection module, the positioning communication module, and the power supply module, and connected to the enable pin of the boost chip via a GPIO interface. The main control module is configured to: when the main control module receives the motion signal output by the motion detection module, control the positioning communication module to enter a high-precision positioning mode. The high-precision positioning mode includes: acquiring satellite positioning data at a first positioning frequency and uploading location information via 4G communication at a first upload frequency, ensuring that the outdoor positioning accuracy of the terminal in motion is ≤1 meter, the hot start time is <5 seconds, and the cold start time is <40 seconds; when the main control module receives the stationary signal output by the motion detection module and the stationary duration exceeds a first preset time threshold, output a shutdown level to the enable pin of the boost chip through the GPIO interface, physically cutting off the positioning communication at the hardware level. The power supply path for the communication module and subsequent circuits is provided to eliminate the static leakage current that still exists in the positioning communication module when the software is off. At the same time, the independent standby power supply output by the buck regulator chip continuously supplies power to the motion detection module, so that the motion detection module can maintain the real-time perception capability of the terminal's motion status even after the boost chip is turned off. When the motion detection module senses a new motion signal, it sends an interrupt signal to the main control module through the hardware interrupt pin. After the main control module is woken up, it restores the power supply to the boost chip through the GPIO interface. The wake-up process is autonomously triggered by the hardware logic of the motion detection module and does not depend on the main control module's timed wake-up or software polling.

[0009] Preferably, in the high-precision positioning mode, the first positioning frequency is 1Hz, the first upload frequency is once every 5 seconds, the outdoor positioning accuracy of the terminal is ≤1 meter, the hot start time is <5 seconds, and the cold start time is <40 seconds.

[0010] Preferably, when the terminal receives the stationary signal and the stationary duration is less than a first preset time threshold, the positioning frequency and data upload frequency are reduced; when the terminal's stationary duration exceeds the first preset time threshold, the boost chip is turned off and the system enters the lowest power consumption mode. In the lowest power consumption mode, the boost chip is turned off, the power supply to the positioning communication module and subsequent circuits is cut off, and only the motion detection module and the main control module are powered by the independent standby power supply output by the buck regulator chip, and the standby current of the entire device is reduced to below 50μA.

[0011] Preferably, the main control module is configured with an anti-shake judgment mechanism: the terminal is determined to be in motion only when the motion detection module outputs motion signals multiple times in a row; the terminal is determined to be in a stationary state only when the motion detection module outputs stationary signals multiple times in a row.

[0012] Preferably, the main control module obtains base station location and signal strength data through the positioning communication module, and selects a positioning strategy based on the motion detection results: in open environments, a high-precision positioning mode is enabled, and in obstructed environments, the mode is switched to base station-assisted positioning.

[0013] Preferably, the main control module also collects the electrical parameters of the lithium battery in real time through the lithium battery protection chip, and controls the charging management chip to switch charging modes based on the electrical parameters; the charging modes include trickle charging mode, constant current charging mode and constant voltage float charging mode, and the main control module switches between the three charging modes according to the battery voltage fed back by the lithium battery protection chip; when a battery abnormality is detected, the main control module outputs a shutdown level to the enable pin of the boost chip through the GPIO interface to cut off the power supply to the back-end load.

[0014] Preferably, the terminal is equipped with a screen interface to support external display devices for real-time display of location information, battery level, and device operating status.

[0015] Compared with the prior art, the present invention has the following beneficial effects: This invention addresses the problems of motion detection stopping when stationary to save power and the response delay and power consumption caused by relying on timed wake-up / software polling in existing solutions. The main control module outputs motion / stationary signals in real time through the motion detection module and dynamically switches the working mode: high-precision positioning during movement; after a timeout when stationary, the main control shuts down the boost chip through GPIO and physically cuts off the power supply to the positioning communication module to eliminate static leakage current, reducing the standby current to below 50μA; at the same time, an independent standby power supply continuously powers the motion detection module. After motion is detected, the main control is woken up and power is restored through a hardware interrupt. The wake-up process is triggered autonomously by hardware logic, without relying on timed wake-up or software polling, thus resolving the contradiction between power saving and response.

[0016] In this invention, the power supply path for the terminal to cut off the load due to power saving is the same as the power supply path for the load to cut off due to battery protection. Both are controlled by the main controller through the same GPIO interface to control the same boost chip to perform the shutdown. Compared with the existing technology where power management and safety protection are set up with separate cut-off switches, the number of hardware components is reduced, and the response time of the two control outputs is consistent.

[0017] This invention uses a lithium battery protection chip to collect the battery's voltage, current, and temperature parameters in real time. The main controller dynamically switches between trickle, constant current, and constant voltage charging modes based on these parameters. Compared with existing fixed threshold hardware protection schemes, this invention offers a more refined charging strategy and greater adaptability.

[0018] This invention uses a highly integrated main control chip to simultaneously achieve 4G communication and GNSS high-precision positioning. It has a compact structure and is suitable for various IoT scenarios such as vehicle positioning and logistics tracking. Attached Figure Description

[0019] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. It should be noted that the following embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the invention. Various modifications and equivalent substitutions made by those skilled in the art without departing from the spirit and scope of the present invention should be considered within the scope of protection of the present invention.

[0020] Figure 1 This is a hardware connection block diagram of the present invention.

[0021] Figure 2 This is a schematic diagram of the power module circuit connection.

[0022] Figure 3 Flowchart for motion-adaptive low-power control.

[0023] Figure 4 Flowchart for coordinated charging and discharging safety control.

[0024] Figure 5 Flowchart for base station-assisted fusion positioning and remote interactive control.

[0025] Figure 6 This is a flowchart illustrating the switching process of the terminal's working state in a vehicle positioning scenario.

[0026] Figure 7 This is a flowchart illustrating the switching process of terminal working status in a logistics tracking scenario. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited thereto.

[0028] Figure 1 A hardware connection block diagram of the terminal of the present invention is shown. For example... Figure 1 As shown, this invention provides an adaptive low-power 4G dual-mode positioning terminal, which consists of four main hardware modules: a main control module, a positioning and communication module, a motion detection module, and a power supply module, all electrically connected to form a unified hardware platform. The main control module uses a highly integrated chip (such as the 780EGH), supporting TDD / FDD multi-band 4G communication and GNSS high-precision positioning, and has built-in Flash and RAM for firmware storage and data processing. The positioning and communication module integrates a GPS+BeiDou dual-mode positioning unit and a 50Ω impedance-matched coplanar waveguide antenna circuit, responsible for satellite navigation signal reception and location data parsing. The motion detection module includes an accelerometer and a signal processing unit, used to collect the terminal's motion / stationary state in real time and output status signals. The power supply module consists of a TP4056 charging management chip, a DW07D lithium battery protection chip, and a two-stage voltage regulator circuit composed of an SDB628 boost chip and an XC6219 buck chip, providing a safe and stable power supply for the entire device.

[0029] Based on the aforementioned hardware, the main control module is configured to implement two core control logics: motion-adaptive low-power control and charge / discharge coordinated safety control. Motion-adaptive low-power control dynamically switches the operating mode of the positioning communication module according to the motion or stationary signal output by the motion detection module: when in motion, it enters a high-precision positioning mode (outdoor accuracy ≤1 meter, hot start <5 seconds, cold start <40 seconds); when stationary, it enters a low-power positioning mode (two-stage power reduction, shutting down the boost chip in the lowest power mode, with standby current reduced to below 50μA). Charge / discharge coordinated safety control collects battery voltage, current, and temperature parameters in real time via the DW07D. The main control module dynamically adapts the TP4056 to trickle / constant current / constant voltage charging modes based on these parameters. Upon detecting overvoltage, overcurrent, over-discharge, or high-temperature anomalies, it immediately shuts down the SDB628 via GPIO, cutting off the load power supply and achieving hardware-level safety protection.

[0030] In this invention, the high-precision positioning mode refers to the following: the main control module controls the positioning communication module to acquire GPS + BeiDou satellite positioning data at a first positioning frequency (e.g., 1Hz), and uploads the location information to the cloud via the 4G communication module at a first upload frequency (e.g., once every 5 seconds). At this time, the positioning accuracy is ≤1 meter, the hot start time is <5 seconds, and the cold start time is <40 seconds. The low-power positioning mode includes a tiered low-power mode and a minimum power mode. In the tiered low-power mode, the positioning frequency is reduced from 1Hz to 0.1Hz (once every 10 seconds), and the upload frequency is reduced from once every 5 seconds to once every 1 minute. In the minimum power mode, the main control module shuts down the boost chip via GPIO, completely cutting off the power supply to the positioning communication module and subsequent circuits, retaining only the standby power supply for the motion detection module and the main control module. The standby current can be reduced to below 50μA.

[0031] In addition, the terminal also integrates auxiliary functions such as base station-assisted fusion positioning, remote policy updates and interaction, anti-shake judgment, hierarchical shutdown and wake-up recovery, which further improves environmental adaptability, battery life and ease of use.

[0032] The coordination between the various parts of this terminal is as follows: the main control module controls the boost chip's shutdown and startup via the GPIO interface; after the boost chip is shut down, the positioning communication module and subsequent circuits are completely powered off, but the motion detection module is continuously powered by the independent standby power supply output from the buck regulator chip; when the motion detection module senses motion, it directly wakes up the main control module via a hardware interrupt pin, without relying on the main control module's timed wake-up or software polling; after being woken up, the main control module restores the boost chip's power supply via GPIO. Furthermore, the power supply path for the terminal to cut off the load due to power saving is the same as the power supply path for cutting off the load due to battery protection; both are controlled by the main control module through the same GPIO interface to shut down the same boost chip.

[0033] The following combination Figures 1 to 7 The technical solution of the present invention will be described in detail below, along with specific embodiments.

[0034] Example 1 This embodiment provides an adaptive low-power 4G dual-mode positioning terminal. This terminal can adaptively switch positioning modes according to motion status and achieve coordinated charging and discharging safety control. The following describes... Figures 1 to 5 The workflow of this terminal is described in detail, including the following steps: S1. Terminal power-on and initialization, including the following process: Step S11: The main control module 110 is powered on and the firmware program is loaded from the built-in Flash memory to the RAM (Random Access Memory), completing the initialization of peripherals such as system clock, GPIO (General Purpose Input / Output Interface), serial port, and I2C (Internal Integrated Circuit Bus).

[0035] At this point, the GPIO (General Purpose Input / Output Interface) of the main control module has been configured in output mode to control the enable pin of the boost chip; the interrupt pin has been enabled, enabling it to respond to the interrupt signal of the motion detection module; the I2C (Internal Integrated Circuit Bus) has been configured, and the acceleration data of the motion detection module and the electrical parameters of the lithium battery protection chip can be read through this bus.

[0036] Step S12: The main control module 110 sequentially detects and initializes each peripheral module, specifically including: detecting the positioning and communication module 120, confirming that the GPS+BeiDou dual-mode positioning unit and the 50Ω coplanar waveguide antenna are working normally, and setting the initial positioning mode to low-power standby mode; detecting the motion detection module 130, configuring the sampling rate (e.g., 10Hz) and interrupt threshold of the MPU6050 accelerometer, and enabling motion detection interruption; detecting the power module 140, reading the battery voltage, current, temperature and state of charge (SOC) fed back by the DW07D lithium battery protection chip 142, and confirming that the battery power is normal; and setting the charging mode of the TP4056 charging management chip 143 to standby mode.

[0037] Step S13: The main control module 110 establishes an MQTT long connection with the cloud server through the positioning communication module and registers the terminal ID, preparing to receive remote policies. At the same time, the main control module 110 reports its current working status (initially in static low-power mode) to the cloud.

[0038] After initialization, the main control module enters a low-power standby state, does not actively execute any business processes, but waits for external events such as motion detection interruption, charging power supply insertion, or timer timeout to trigger before entering the corresponding processing flow.

[0039] S2. Motion state detection and image stabilization determination, including the following process: Step S21: The motion detection module 130 collects the acceleration data of the terminal in real time, filters out high-frequency noise through an internal low-pass filter, obtains the original motion / stationary signal, and outputs it to the main control module 110.

[0040] Step S22: The main control module 110 executes the anti-shake judgment mechanism, determining that the terminal has entered a motion state only when the motion detection module outputs motion signals multiple times consecutively; and determining that the terminal has entered a stationary state only when the motion detection module outputs stationary signals multiple times consecutively. Specifically, this includes: Set two counters, Cnt_motion and Cnt_static, with an initial value of 0 for both.

[0041] The main control module reads the output signal of the motion detection module every 100ms. Specifically, if the current signal is a motion signal, Cnt_motion is incremented by 1 and Cnt_static is cleared to zero. When Cnt_motion ≥ 3 (3 consecutive motion signals), the terminal is determined to be in motion. If the current signal is a stationary signal, Cnt_static is incremented by 1 and Cnt_motion is cleared to zero. When Cnt_static ≥ 3 (3 consecutive stationary signals), the terminal is determined to be in stationary state.

[0042] If the counter does not reach the threshold, the state remains unchanged and monitoring continues; once the judgment result changes, the main control module immediately records the state switching timestamp and enters the corresponding control process.

[0043] S3, motion-adaptive low-power control Figure 3 The motion-adaptive low-power control flow is shown, which specifically includes the following process: Step S31: When it is determined to be a motion state (e.g.) Figure 3 (Left branch), perform the following steps: The main control module 110 enables the SDB628 boost chip 144 via GPIO (if it has been previously turned off) and waits for the voltage to stabilize in 1ms.

[0044] The main control module 110 starts the GPS+BeiDou dual-mode positioning and communication module via serial port command, sets the positioning frequency to 1Hz (high-precision continuous positioning), and opens the data upload channel of the 4G communication module.

[0045] The main control module 110 receives NMEA data output by the positioning and communication module in real time, analyzes latitude, longitude, speed, and azimuth, and uploads it to the cloud server every 5 seconds via the 4G communication module.

[0046] In motion mode, the main control module continuously monitors the output of the motion detection module. If a stationary signal is detected three times in a row, the process proceeds to step S32.

[0047] Step S32, when the state is determined to be stationary (e.g.) Figure 3 (Right branch), execute a tiered low-power strategy: 1) Level 1 Low Power Mode (Graded Low Power), specifically: The main control module 110 reduces the positioning frequency of the positioning communication module from 1Hz to 0.1Hz (positioning once every 10 seconds); reduces the 4G data upload frequency from once every 5 seconds to once every 1 minute (or adopts batch upload method); starts the static timer Timer_static to record the static duration; keeps the SDB628 boost chip working normally, only reducing the operating frequency of peripherals.

[0048] 2) Second-level low-power mode (lowest power mode), specifically: When the Timer_static time exceeds the first preset time threshold (5 minutes in this embodiment), the main control module 110 further shuts off the power supply to the GPS+BeiDou dual-mode positioning communication module; it only enables base station assisted positioning (by obtaining Cell ID and RSRP through the 4G module to estimate the location), or completely disables the positioning function; Figure 2 The circuit connection of the power supply module is shown. The main control module outputs a low level through GPIO to turn off the enable pin of the SDB628 boost chip 144, thereby cutting off the power supply to the positioning module, the 4G communication module, and their subsequent circuits (see [link]). Figure 2 (Power module connection); only the 3.3V standby power output from the XC6219 low-dropout regulator 145 is retained to power the RTC and wake-up interrupt logic of the motion detection module 130 and the main control module 110. Actual measurements show that the standby current of the entire device can be reduced to below 50μA in this mode.

[0049] Step S33, Wake-up and recovery from a resting state: When the terminal is in the lowest power consumption mode (SDB628 is off), the motion detection module 130 still operates under standby power. Once the motion detection module detects that the acceleration amplitude exceeds the preset motion threshold (e.g., 0.5g), it immediately wakes up the main control module 110 by outputting a high level through the interrupt pin. After the main control module is woken up, it first enables SDB628 by outputting a high level through GPIO, waits for the voltage to stabilize (about 1-2ms), then reinitializes the positioning module and the 4G communication module, and jumps to step S31.

[0050] S4. Charge and discharge coordinated safety control Figure 4 The charging and discharging coordinated safety control process is illustrated. In this step, the GPIO interface of the boost chip and the boost chip are shut down due to battery abnormality, which is the same interface and the same chip as the GPIO interface of the boost chip and the boost chip are shut down due to the terminal being stationary in step S322. That is, the power supply path of the terminal cutting off the load due to power saving and the power supply path of the load cutting off due to battery protection are the same path. In existing solutions, power saving control and safety protection are executed through different switches, and the two functions are independent of each other; in this application, the two control logics share the same execution path, which is more streamlined in hardware implementation, and the response time of the two control outputs is consistent. Figure 4 As shown, it specifically includes: Step S41: Real-time acquisition of battery parameters: The DW07D lithium battery protection chip 142 monitors the voltage, current, and temperature of the lithium battery 141 in real time and transmits the data to the main control module 110 via the I2C interface. The main control module reads the data every second and updates the SOC estimate.

[0051] Step S42, Dynamic Adaptation of Charging Mode: When USB power is detected, the main control module 110 enables the TP4056 charging management chip 143 via GPIO; the main control module controls the TP4056 to switch charging modes based on the battery voltage and SOC fed back by DW07D, specifically: 1) If the battery voltage is <3.0V (over-discharge state), use trickle charging and set the charging current to 100mA.

[0052] 2) If the battery voltage is between 3.0V and 4.1V, use constant current fast charging and set the charging current to 1A.

[0053] 3) If the battery voltage is ≥4.1V, switch to constant voltage float charging. The voltage will stabilize at 4.2V and the current will gradually decrease.

[0054] During charging, the main control module continuously monitors the battery temperature. If the temperature exceeds 45°C, it automatically reduces the charging current to 500mA.

[0055] Step S43, Abnormal Protection and Load Disconnection: The main control module 110 compares the parameters fed back by DW07D with the preset thresholds in real time (overvoltage ≥ 4.3V, overcurrent ≥ 1.5A, over-discharge ≤ 2.8V, high temperature ≥ 60℃). When any anomaly is detected, the main control module immediately performs the following actions: The GPIO output of a shutdown signal to the enable pin of the SDB628 stops the boost output and cuts off power to all loads. The location communication module reports the anomaly type (e.g., "overvoltage protection") and current battery parameters to the cloud. The terminal enters a fault sleep state, awaiting manual intervention or automatic recovery after the anomaly is resolved.

[0056] S5, base station-assisted fusion positioning control Figure 5 The process of base station-assisted fusion positioning and remote interactive control is illustrated. For example... Figure 5 As shown, step S5 specifically includes the following process: Step S51: The main control module 110 obtains the Cell ID, frequency point, signal strength (RSRP / RSRQ) and list of neighboring cells of the serving cell in real time through the 4G communication module.

[0057] Step S52: Based on the current motion state and satellite signal quality, dynamically select a positioning strategy (e.g., Figure 5 (as shown) If the terminal is in motion and there are ≥4 visible satellites, and RSRP > -95dBm, then GPS + BeiDou high-precision positioning will be used first, with a positioning accuracy of ≤1 meter. If the terminal is in an indoor or underground parking garage or other obstructed environment with weak satellite signals (<3 visible satellites), then it will automatically switch to base station-assisted positioning. Specifically, the main control module will look up the cell ID in a table (locally pre-stored or cloud-downloaded cell location database) to estimate the terminal's location. If there are multiple cell signals, a triangulation algorithm (based on RSRP value) will be used to calculate a more accurate location, with a positioning accuracy of approximately 50-200 meters.

[0058] If the terminal is in the lowest power consumption mode (SDB628 is off), it will rely on base station-assisted positioning throughout the process and will not activate satellite positioning.

[0059] S6. Human-computer interaction and status display, specifically: The terminal is equipped with a 2.8-inch screen interface, supporting external SPI serial screens. The main control module outputs the following information to the screen display in real time: Current positioning mode (high precision / low power / base station assisted), real-time latitude and longitude, speed, battery percentage and charging status, 4G signal strength, and device runtime.

[0060] Figure 6 This illustrates the complete workflow for switching the working state of the aforementioned positioning terminal in a vehicle-mounted positioning scenario. For example... Figure 6 As shown, taking a vehicle-mounted positioning application scenario as an example, the collaborative working process of steps S1-S6 above is explained. The specific steps are as follows: When the vehicle is stationary (off): After the terminal is powered on, the motion detection module outputs a stationary signal three times consecutively. The main controller determines that the vehicle is stationary and enters the first-level low-power mode (positioning frequency 0.1Hz, upload cycle 1 minute). After 5 minutes, it enters the second-level lowest power mode: the main controller shuts down the SDB628, the positioning and 4G modules are powered off, and only the motion sensor is in standby mode with a standby current of 50μA.

[0061] Vehicle Start-up (Motion Detection Wake-up): The motion sensor detects an acceleration exceeding 0.5g, and the interrupt pin wakes up the main controller. The main controller enables the SDB628, restores power, reinitializes the positioning and communication module, initiates GPS+BeiDou high-precision positioning, and achieves positioning within 8ms. Positioning accuracy is ≤1 meter, and the warm-up time is approximately 3 seconds. 4G upload resumes every 5 seconds.

[0062] Upon entering an underground parking garage (obstructed environment): Satellite signal is lost. The main controller automatically switches to base station-assisted positioning, estimates the location using Cell ID and RSRP, and continues to report location information to avoid positioning interruption.

[0063] The vehicle returns to the ground: satellite signal is restored (visibility count ≥ 4), and the main control immediately switches back to GPS + Beidou high-precision positioning.

[0064] Vehicle off and then stationary again: Repeat the process of vehicle off and stationary (stationary state) and enter low-power sleep mode.

[0065] The above process fully demonstrates the multiple advantages of this invention, such as motion-adaptive low power consumption, safe charging and discharging, base station integration, and remote interaction, and can achieve the unity of ultra-long standby time and high-precision positioning.

[0066] Example 2 This embodiment provides another adaptive low-power 4G dual-mode positioning terminal, highlighting the functions of dynamic remote strategy updates and adaptive adjustment of anti-shake parameters. This embodiment uses cargo logistics tracking as an application scenario; the terminal is installed on goods or pallets to achieve full-process tracking during warehousing, transportation, and transshipment.

[0067] Step 1, Terminal Deployment and Initial Configuration, including: Installing the terminal on the goods or pallet, and synchronizing strategy parameters from the cloud after initialization: continuous anti-shake count N=3, static grading time threshold T1=5 minutes (level 1), T2=30 minutes (level 2), and positioning and upload frequency are the same as in Example 1.

[0068] Step 2, Long-term inactivity and remote policy update, the specific steps are as follows: 1) After the goods remain stationary in the warehouse for more than T2, they enter the lowest power consumption mode: the main controller shuts down the SDB628 boost chip through GPIO, the positioning and 4G modules are powered off, and only the motion detection module and the main controller RTC are powered by the XC6219 standby power supply, and the overall current drops to below 50μA.

[0069] 2) The logistics management platform needs to adjust the static grading thresholds to T1=10 minutes and T2=45 minutes (to accommodate longer transit waiting times). The platform sends paging commands to the terminal via the 4G network (the terminal's 4G module supports periodic paging monitoring in PSM power-saving mode). After the 4G module detects the paging, it wakes up the main controller via the interrupt pin.

[0070] 3) After the main controller is woken up, it first enables the SDB628 through GPIO to restore the boost power supply, waits for the voltage to stabilize (about 1-2ms), and then reinitializes the 4G communication module to establish a connection with the cloud.

[0071] 4) The terminal receives the new policy parameters, stores them in Flash, updates the local control variables, and then re-enters the lowest power mode.

[0072] Step 3: Adaptive adjustment of anti-shake parameters, including: brief vibrations caused by forklifts passing through the warehouse or the movement of adjacent goods may lead to false motion signals output by the motion detection module, causing false wake-ups of the terminal; the main control module counts the number of false wake-ups over 30 consecutive days. If the number of false wake-ups exceeds 10, the consecutive anti-shake count N is automatically increased from 3 to 4 and recorded in the local log; when the terminal actively wakes up again (or reports periodically), the adjusted N value is reported to the cloud, and the cloud can update the strategy synchronously to achieve self-learning optimization of the terminal.

[0073] Step 4: Positioning strategy in obstructed environments, including situations where GPS signals are weak inside warehouses or freight vehicles, and the terminal cannot receive satellite signals while in motion (e.g., goods being moved or transported). The main controller obtains the serving cell CellID and neighboring cell RSRP values ​​through the 4G module and uses base station triangulation to estimate the location (accuracy approximately 50-200 meters). When the goods are moved to an open outdoor area and satellite signals are restored (visibility ≥ 4), the main controller automatically switches back to GPS + BeiDou high-precision positioning (accuracy ≤ 1 meter), as detailed in Example 1, S5.

[0074] Figure 7 This illustrates the terminal's working state switching process in a logistics tracking scenario. The following example uses another specific use case, a complete logistics tracking scenario, as an example. Figure 7 The diagram illustrates the collaborative working process of the above steps, which includes the following specific steps: 1) If goods remain stationary in the warehouse for more than 30 minutes, the terminal enters the lowest power consumption mode, with a standby voltage of 50μA.

[0075] 2) The logistics management platform remotely modifies the static threshold (T1 is changed to 10 minutes, T2 is changed to 45 minutes), wakes up the terminal through 4G paging response, and the terminal returns to sleep after receiving the parameters.

[0076] 3) When the forklift is moving goods, the motion sensor detects an acceleration exceeding 0.5g, triggering an interrupt and waking up the main controller. The main controller enables the SDB628 and starts base station-assisted positioning (there is no GPS in the warehouse), reporting the location trajectory at a motion frequency (5 seconds / time).

[0077] 4) Once the goods are loaded onto the transport vehicle and driven out of the warehouse to the outdoors, the satellite signal is restored, and the terminal automatically switches to GPS+BeiDou high-precision positioning with an accuracy of ≤1 meter, and continues to report, achieving high-precision tracking during transportation.

[0078] 5) When the goods arrive at the transit station and are unloaded into another warehouse (indoors), the satellite signal is lost, and the terminal switches back to the base station for assisted positioning.

[0079] 6) If the goods remain stationary for more than 10 minutes (new T1), they will enter the first-level low-power mode (positioning frequency 0.1Hz, upload cycle 1 minute); if they remain stationary for more than 45 minutes (new T2), they will enter the lowest power mode, shut down SDB628, and standby 50μA.

[0080] The above process demonstrates the complete collaborative capabilities of this invention in logistics tracking scenarios, including remote strategy dynamic updates, anti-shake adaptive operation, seamless switching between base station and satellite positioning, and hierarchical deep energy saving.

[0081] Example 3 Based on Embodiments 1 and 2 above, this embodiment further elaborates on another implementation method of motion detection in step S2, including the following steps: S21. Motion trajectory generation and smooth transition method, the specific steps are as follows: S211, the main control module 110 records the terminal's location coordinates (longitude, latitude, and altitude) at each sampling moment based on the location data output by the positioning and communication module (whether it is GPS+BeiDou high-precision positioning or base station assisted positioning results), forming the original trajectory point set.

[0082] S212. When the terminal switches from a moving state to a stationary state (e.g., the vehicle is turned off and parked), the motion detection module 130 outputs a stationary signal three times consecutively, and the main controller determines that it has entered a stationary state. At this time, the main control module marks the current position as the stationary starting point and stops updating the position (keeping the last position coordinates), and sets the speed and direction to zero.

[0083] S213. When the terminal switches from a stationary state back to a moving state (e.g., the vehicle restarts), the motion detection module detects that the acceleration exceeds a threshold, the main control module wakes up, and reacquires positioning data. To avoid discontinuous jumps in the trajectory (e.g., jumping directly from the last stationary position to a newly acquired distant position), the main control module uses linear interpolation to smooth the trajectory points during the transition period. The linear interpolation formula is:

[0084] In the formula, These are the coordinates of the last trajectory point before the stationary state ends. The coordinates of the first valid positioning point after the start of the movement. The coordinates of intermediate trajectory points generated by interpolation. By generating several intermediate points, the trajectory becomes continuous and smooth at both the visual and algorithmic levels, avoiding abrupt changes.

[0085] S214. In motion, each time the main control module receives a positioning point, it calculates the instantaneous velocity based on the distance difference and time difference between the current point and the previous point. And the orientation angle (calculated based on the difference between latitude and longitude). These motion parameters, along with the location data, are uploaded to the cloud and can be displayed in real time on an external screen.

[0086] S22. Refined Algorithm for Base Station Assisted Positioning (Optional AOA / TOA Enhancement Implementation). This embodiment provides a base station assisted positioning method that is more accurate than cell positioning, suitable for scenarios requiring medium accuracy (meter-level to ten-meter-level) and where satellite signals are unavailable. The main control module 110 receives channel impulse response (CIR) signals from the serving base station and two adjacent base stations via a 4G communication module. This signal is emitted by multiple antenna arrays of the base station and carries amplitude, phase, and delay information of the signal along different paths; the main control module samples and performs analog-to-digital conversion on the CIR signal to construct a data matrix for estimating the angle of arrival (AOA) and time of arrival (TOA).

[0087] The ESPRIT algorithm is used to perform eigenvalue decomposition on the data matrix, separating the signal subspace and the noise subspace. Specifically, this includes: processing the data matrix constructed in the above steps... Covariance matrix estimation is performed to obtain the covariance matrix. ,in Representation matrix The conjugate transpose of the covariance matrix; Perform eigenvalue decomposition ,in The eigenvector matrix, This is an eigenvalue diagonal matrix, with the eigenvalues ​​arranged in descending order. ( (Total number of array elements); estimated based on the number of signal sources. (i.e., the number of paths, which can be determined by the Akaike Information Criterion or the Minimum Description Length Criterion), and the feature vector matrix. Divided into signal subspace (corresponding to the previous) (the largest eigenvalue) and noise subspace (corresponding to the remaining) (one eigenvalue); from the signal subspace Extract two subarrays and , respectively corresponding to the first in the array Each array element and the back The received signal subspace of each array element. According to the rotation invariance principle of the ESPRIT algorithm, the two subarrays satisfy a rotation invariance relationship. ,in It is a rotation factor matrix containing information on the signal's angle of arrival (AOA) and time delay (TOA).

[0088] Two rotation-invariant subspaces are constructed based on the signal subspace. The rotation factor is estimated by the least squares method, and the arrival angle and time delay of the line-of-sight path (LOS) or the main reflection path are extracted from them.

[0089] By combining the known base station coordinates, the approximate location of the terminal is calculated using geometric relationships (triangulation or hyperbolic positioning). When multiple base station signals are available, the least squares method is used to fuse multiple sets of AOA / TOA results to improve positioning accuracy.

[0090] S23. If the terminal is in the lowest power consumption mode (SDB628 off), the main control module does not perform the above complex calculations, but only uses simple Cell ID positioning or RSRP triangulation (accuracy 50-200 meters) to save power. When the terminal is in motion and the battery is fully charged, this refined algorithm can be used to obtain higher accuracy (accuracy up to 10-30 meters).

[0091] Example 4 This embodiment, based on the above-described Embodiment 1 and Embodiment 2, verifies the technical effects of this application through experiments.

[0092] All experimental data were obtained under the following standard conditions: ambient temperature 25℃±2℃, battery voltage 3.7V (nominal voltage), battery capacity 1000mAh, main control chip 780EGH, and motion detection module MPU6050 (sampling rate 10Hz).

[0093] 1. Power Consumption Comparison Experiment Table 1 presents experimental data comparing the overall power consumption of the proposed solution and existing software hibernation solutions under different operating modes.

[0094] Table 1

[0095] As shown in Table 1, under the same hardware platform (780EGH main controller, GPS+BeiDou dual-mode positioning module, 4G communication module) and the above standard test conditions, the control scheme of this application and an existing software hibernation scheme were run respectively, and the power consumption of the whole machine in each working mode was recorded.

[0096] The basic idea behind the existing software hibernation solution is to determine the terminal's motion or stationary state using an accelerometer. When the terminal is determined to be stationary, the main control CPU enters hibernation mode, and the power supply to the positioning module is shut down via software to reduce power consumption. However, this solution has the following drawbacks: the power path of the positioning module remains connected after the software shutdown, resulting in static leakage current in the subsequent circuitry; at the same time, the motion detection function also stops after the CPU goes into hibernation, requiring timed wake-up or software polling to re-detect the terminal's motion state.

[0097] In motion mode (high-precision positioning mode, positioning frequency 1Hz), the power consumption of the proposed solution and the existing solution is approximately 120mA, with no significant difference between the two.

[0098] In a stationary state (frequency reduction mode, positioning frequency 0.1Hz), the power consumption of the existing solution is about 35mA. The solution of this application reduces the positioning frequency and 4G upload frequency, and the power consumption is about 30mA, which is about 14% lower than the existing solution.

[0099] In the lowest power consumption mode (long-term inactivity), the existing solution consumes approximately 3mA. Although the CPU is in sleep mode and the positioning module's power supply is software-disabled, the static leakage current in the subsequent circuits cannot be eliminated because the positioning module's power path remains connected. This application's solution directly shuts down the boost chip via GPIO, physically cutting off all power supply paths to the subsequent circuits from the power source, completely eliminating static leakage current and reducing the overall standby current to below 50μA. Compared to the existing solution's approximately 3mA standby power consumption, this application reduces power consumption by approximately 98% in the lowest power consumption mode.

[0100] 2. Charge and discharge protection comparison experiment Table 2 presents comparative experimental data on the charge and discharge protection performance of the proposed solution and existing pure hardware protection solutions.

[0101] Table 2

[0102] As shown in Table 2, under the same hardware platform and the above standard test conditions, the protection control scheme of this application and an existing pure hardware protection scheme were run respectively, and the protection response time, protection threshold adjustability, charging mode adaptability, and whether the power consumption control shares the execution path were recorded.

[0103] The basic idea behind the existing pure hardware protection scheme is to monitor the battery voltage through a voltage detection circuit. When the voltage exceeds a fixed threshold, an independent hardware load protection switch directly cuts off the battery's power supply to the load. The drawbacks of this scheme are: the protection threshold is set by hardware and is fixed at the factory; the protection circuit and power management circuit operate independently, with the protection circuit still in full-power standby mode when the terminal is in a low-power sleep state; and each of the protection circuit and power management circuit has its own independent cut-off switch, increasing hardware costs.

[0104] Regarding protection response time, the existing solution is directly triggered by hardware logic, with a response time of less than 1 microsecond; the solution in this application reads battery parameters via I2C, and after judgment by the main controller, outputs a shutdown signal via GPIO, with a response time of less than 100 microseconds. Although the response time of this application is slightly longer than that of the existing solution, it fully meets the battery safety protection requirements (battery manufacturers typically require a protection response time of less than 1 millisecond), which is acceptable in engineering applications.

[0105] Regarding the adjustability of the protection threshold, the protection threshold of the existing solution is set by hardware and is fixed and cannot be adjusted after leaving the factory (usually fixed at around 6.5V); the protection threshold of the solution in this application is set by software and can be flexibly adjusted according to the battery type or application scenario.

[0106] Regarding charging mode adaptation, the existing solution only supports a single charging mode; the solution in this application dynamically switches between three modes—trickle charging, constant current fast charging, or constant voltage float charging—based on the battery voltage and state of charge, resulting in a more refined charging strategy.

[0107] Regarding the execution path of power consumption control, the existing solution has independent cut-off switches for the protection circuit and the power management circuit, and the two functions operate independently. In the solution of this application, the power supply path for cutting off the load due to power saving and the power supply path for cutting off the load due to battery protection are the same path. Both are controlled by the main controller through the same GPIO interface to control the same boost chip to perform the shutdown, which is more streamlined in hardware implementation, and the response time of the two control outputs is consistent.

[0108] The experimental data above show that the standby power consumption of this application is reduced by about 98% compared with the existing software hibernation scheme in the lowest power consumption mode, while maintaining a wake-up response time of less than 10ms. In terms of charge and discharge protection, although the protection response time is slightly longer than the existing pure hardware protection scheme, it fully meets the safety requirements and has significant advantages in terms of threshold adjustability, charging mode adaptation, and sharing the execution path with power consumption control.

[0109] The above embodiments are merely examples and illustrations of the structure of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the structure of the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. An adaptive low-power 4G dual-mode positioning terminal, wherein the terminal is integrated on a substrate, characterized in that, include: Integrated on the substrate: The motion detection module is used to collect the acceleration data of the terminal in real time and output motion signals or stationary signals based on the acceleration data. The positioning and communication module is used to acquire the terminal's location data and transmit it. The power module includes a charging management chip, a lithium battery protection chip, a boost chip, and a buck regulator chip. The boost chip has an enable pin, and the buck regulator chip outputs an independent standby power supply. The main control module is electrically connected to the motion detection module, the positioning communication module and the power supply module respectively, and is connected to the enable pin of the boost chip through the GPIO interface; The main control module is configured as follows: When the motion signal is received, the positioning communication module is controlled to enter a high-precision positioning mode. The high-precision positioning mode includes: acquiring satellite positioning data at a first positioning frequency and uploading location information via 4G communication at a first upload frequency. When the stationary signal is received and the stationary duration exceeds a first preset time threshold, a shutdown level is output to the enable pin of the boost chip via the GPIO interface, physically cutting off the power supply path to the positioning communication module and subsequent circuits at the hardware level. Simultaneously, the independent standby power supply output by the buck regulator chip continuously powers the motion detection module. When the motion detection module detects a motion signal, the hardware interrupt pin sends an interrupt signal to the main control module, the GPIO interface restores the power supply to the boost chip, and the terminal's wake-up process is autonomously triggered by the hardware logic of the motion detection module.

2. The adaptive low-power 4G dual-mode positioning terminal according to claim 1, characterized in that, In the high-precision positioning mode, the first positioning frequency is 1Hz, the first upload frequency is once every 5 seconds, the outdoor positioning accuracy of the terminal is ≤1 meter, the hot start time is <5 seconds, and the cold start time is <40 seconds.

3. The adaptive low-power 4G dual-mode positioning terminal according to claim 1, characterized in that, When the main control module receives the stationary signal and the stationary duration is less than a first preset time threshold, it reduces the positioning frequency and data upload frequency. When the main control module receives the stationary signal and the stationary duration exceeds the first preset time threshold, it shuts down the boost chip and enters the lowest power consumption mode. In the lowest power consumption mode, the boost chip is in the off state, the power supply to the positioning communication module and the subsequent circuit is cut off, and only the motion detection module and the main control module are powered by the independent standby power supply output by the buck regulator chip, and the standby current of the whole machine is reduced to below 50μA.

4. The adaptive low-power 4G dual-mode positioning terminal according to claim 1, characterized in that, The main control module is equipped with an anti-shake judgment mechanism, which is as follows: the terminal is determined to enter a motion state only when it receives multiple consecutive motion signals from the motion detection module; the terminal is determined to enter a stationary state only when it receives multiple consecutive stationary signals from the motion detection module.

5. The adaptive low-power 4G dual-mode positioning terminal according to claim 1, characterized in that, The main control module obtains base station location and signal strength data through the positioning communication module, and selects a positioning strategy based on the motion detection results: for open environments, it enables high-precision positioning mode; for occluded environments, it switches to base station assisted positioning.

6. The adaptive low-power 4G dual-mode positioning terminal according to claim 1, characterized in that, The main control module also collects the electrical parameters of the lithium battery in real time through the lithium battery protection chip, and controls the charging management chip to switch charging modes based on the electrical parameters; the electrical parameters include at least: voltage, current and temperature.

7. The adaptive low-power 4G dual-mode positioning terminal according to claim 6, characterized in that, The main control module is also configured to output a shutdown level to the enable pin of the boost chip through the GPIO interface when the electrical parameter is detected to exceed a preset safety threshold, thereby cutting off the power supply to the back-end load.

8. The adaptive low-power 4G dual-mode positioning terminal according to claim 6, characterized in that, The charging modes include trickle charging mode, constant current charging mode, and constant voltage float charging mode; the main control module controls the charging management chip to switch between the trickle charging mode, constant current charging mode, and constant voltage float charging mode according to the electrical parameters fed back by the lithium battery protection chip.

9. The adaptive low-power 4G dual-mode positioning terminal according to claim 1, characterized in that, The terminal is equipped with a screen interface, which supports external display devices for real-time display of location information, battery level, and device operating status.

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