A radar-sensing wall clock intelligent backlight control system

Abstract

The application discloses a radar-sensed wall clock intelligent backlight control system, which comprises a radar sensing module, a main control module, an ambient light detection module, a backlight driving module, a backlight emitting module, a power module and a parameter configuration module; the main control module is electrically connected with the radar sensing module, the ambient light detection module, the backlight driving module, the backlight emitting module and the parameter configuration module; the power module is electrically connected with the radar sensing module, the main control module, the ambient light detection module, the backlight driving module, the backlight emitting module and the parameter configuration module; and the modules work cooperatively to realize full intelligent control of the wall clock backlight. The radar-sensed wall clock intelligent backlight control system can accurately sense the existence, distance and environmental state of a human body through the radar module, intelligently start and stop the backlight and adaptively adjust the brightness of the backlight by combining with PWM dimming technology, and simultaneously optimizes the module design and the power supply mode, and takes into account the energy saving, practicality, visual comfort and product appearance integrity.

Description

Technical Field

[0001] This invention relates to the field of clock control technology, specifically to a radar-sensing intelligent backlight control system for wall clocks. Background Technology

[0002] Wall clocks, as a traditional timekeeping tool, are widely used in various scenarios such as homes and offices, with their core function being to provide users with accurate time display. With the rapid development of smart home technology, users' functional needs for wall clocks are no longer limited to simple timekeeping; they increasingly demand convenience, energy efficiency, and visual comfort. Backlighting, as an important auxiliary function of wall clocks, has become crucial for enhancing the user experience due to the increasing intelligence of its control methods.

[0003] Currently, wall clock backlight control on the market mainly falls into two categories: manual control and simple sensor control. Manual control requires users to manually turn the backlight on or off, and the brightness cannot adaptively adjust to environmental changes, resulting in poor usability. Manual operation is necessary when getting up at night to read the time, impacting the user experience. Simple sensor control often uses infrared sensors, which have limited sensing range and low accuracy, and are easily affected by ambient light and obstructions, leading to false triggering or insensitive triggering. Furthermore, the exposed installation of infrared sensors can damage the wall clock's appearance and affect its aesthetics. In addition, while some existing smart wall clocks attempt to integrate ambient light detection, they often use analog dimming technology, which is prone to color temperature drift, resulting in inconsistent backlight color and affecting readability and visual comfort. Therefore, developing a precise, intelligent backlight control system that does not damage the wall clock's appearance has become an urgent need for the current intelligent upgrade of wall clocks. Summary of the Invention

[0004] The technical problem to be solved by this invention is to overcome the existing defects and provide a radar-sensing smart backlight control system for wall clocks. The system accurately senses the presence, distance, and environmental conditions of the human body through a radar module, and combines PWM dimming technology to realize intelligent start / stop and adaptive brightness adjustment of the backlight. At the same time, the module design and power supply method are optimized to balance energy saving, practicality, visual comfort, and product appearance integrity, thus solving the defects of the existing technology.

[0005] To achieve the above objectives, the present invention provides a technical solution: A radar-sensing intelligent backlight control system for a wall clock includes a radar sensing module, a main control module, an ambient light detection module, a backlight driving module, a backlight emitting module, a power supply module, and a parameter configuration module. The main control module is electrically connected to the radar sensing module, the ambient light detection module, the backlight driving module, the backlight emitting module, and the parameter configuration module. The power supply module is electrically connected to the radar sensing module, the main control module, the ambient light detection module, the backlight driving module, the backlight emitting module, and the parameter configuration module. The modules work together to achieve fully intelligent control of the wall clock backlight. Among them, the radar sensing module is used to identify the presence of the human body, its distance from the clock, and micro-motion signals, providing parameters for backlight control; The main control module receives human body sensing signals from the radar sensing module and light intensity signals from the ambient light detection module, generates backlight control commands based on a preset algorithm and sends them to the backlight driver module; it also receives commands from the parameter configuration module to adjust the radar detection distance, backlight brightness level, sleep delay parameters, and stores the parameters. An ambient light detection module is used to detect the intensity of ambient light. The backlight driver module is used to receive instructions from the main control module, drive the backlight emission module to work, and achieve precise adjustment of backlight brightness. The backlight module is used to emit backlight, and includes multiple LEDs and a light guide plate, with the LEDs mounted on the light guide plate; The power supply module is used to supply power to each module; The parameter configuration module allows users to manually adjust system parameters.

[0006] Furthermore, the radar sensing module adopts a 24GHz millimeter-wave radar sensing module, which has a built-in radar transmitting circuit, radar receiving circuit and signal processing circuit, and the detection distance can be adjusted to 0.5-5 meters.

[0007] Furthermore, the main control module adopts an STM32F103C8T6 microcontroller, which integrates data processing, logic judgment and instruction output functions, and has a built-in Flash storage unit for storing user-set parameters; the preset algorithm is as follows: when a human body is detected and the distance is within a preset range, the backlight brightness is adjusted according to the ambient light intensity; when the human body is not present or the distance exceeds the preset range, the backlight is turned off after a preset delay and enters a low-power state.

[0008] Furthermore, the ambient light detection module uses a digital ambient light sensor with a measurement range of 0-65535 lux and an operating current of ≤10μA.

[0009] Furthermore, the backlight driving module adopts PWM dimming technology and consists of a PWM signal generation circuit and a constant current driving circuit.

[0010] Furthermore, the constant current drive circuit uses an AO3401 field-effect transistor as the drive chip, and works with a current-limiting resistor to achieve constant current drive. The duty cycle of the PWM signal is adjustable from 0 to 100%.

[0011] Furthermore, the backlight module uses 8-24 soft-light LED beads arranged in a ring, with a rated voltage of 3.3V, a rated current of 20mA, a color temperature of 3000K, and a light guide plate made of PMMA with a thickness of 2mm.

[0012] Furthermore, the power module adopts a dual AC / DC power supply design, can be connected to a 220V AC power supply, and has a built-in rechargeable lithium battery as a backup power supply; it integrates step-down voltage regulation and low-power management circuits to provide stable operating voltage for each module.

[0013] Furthermore, the step-down voltage regulator circuit uses LM1117-3.3 and LM1117-5.0 voltage regulator chips to output stable 3.3V and 5V voltages; the lithium battery is a 3.7V / 1000mAh rechargeable lithium battery with a TP4056 charging management chip. The system power consumption in sleep mode is ≤50mW, and the lithium battery has a full charge life of ≥72 hours.

[0014] Furthermore, the parameter configuration module includes buttons or a touch screen and a Bluetooth communication module. Parameters can be set via buttons or directly on the touch screen, or via a mobile app connected to the Bluetooth module, enabling remote parameter configuration and status viewing to suit different user habits. The parameters that can be set include, but are not limited to, detection distance, backlight brightness, and sleep delay time.

[0015] This invention provides another technical solution: a radar-sensing intelligent backlight control method for wall clocks, based on a radar-sensing intelligent backlight control system for wall clocks, with the following steps: S1 System Initialization: After power-on, the main control module performs self-tests on each module, loads preset parameters, and the radar sensing module and ambient light detection module enter low-power monitoring state, while the backlight emitting module is in the off state. S2 Human Body Sensing Monitoring and Backlight Adjustment: The radar sensing module continuously scans the surrounding environment. When a human body is detected entering the preset detection range (and the micro-movement or stillness of the human body is identified), a human body presence signal is output to the main control module. If no human body is detected, the system maintains a low power consumption state and the backlight remains off. S3 Ambient Light Detection and Backlight Adjustment: After the main control module receives a signal indicating the presence of a human body, it triggers the ambient light detection module to collect the current ambient light intensity data. Based on a preset algorithm, the light intensity is divided into multiple levels, and PWM control commands with different duty cycles are generated and sent to the backlight driver module. S4 Backlight Adjustment: The backlight module lights up and adjusts to the corresponding brightness according to the PWM command, while the main control module continuously receives signals from the radar sensing module. If the human body is within the detection range, the backlight maintains the current brightness. If the human body leaves the detection range, the main control module starts a sleep timer. After the timer reaches the preset delay, the backlight is turned off and the system returns to the low-power monitoring state.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: This radar-sensing intelligent backlight control system for wall clocks has the following advantages: 1. It adopts a 24GHz millimeter-wave radar sensing module, based on FMCW technology and Doppler effect, which can accurately identify the presence, distance and micro-motion signals of the human body, with high sensing accuracy; and can penetrate the non-metallic material of the wall clock shell, without the need for exposed installation, which not only ensures the integrity of the wall clock appearance, but also avoids the problems of traditional infrared sensing modules being susceptible to environmental interference and false triggering, thus improving the reliability of use. 2. Combining radar sensing and ambient light detection, the backlight is intelligently turned on and off and its brightness is adaptively adjusted. No manual operation by the user is required. The backlight can be automatically triggered when the user gets up and approaches at night, and automatically turned off when there is sufficient light during the day, taking into account both convenience and energy saving. At the same time, PWM constant current dimming technology is used to avoid color temperature drift, ensure backlight color consistency, and improve visual comfort.

[0017] 3. Through the parameter configuration module, users can adjust parameters such as detection distance, backlight brightness, and sleep delay according to their own needs to adapt to different usage scenarios and user habits; the number of LEDs and the color of light emitted by the backlight module can be flexibly adjusted to adapt to different specifications of wall clock products.

[0018] 4. The overall structural design is reasonable, which facilitates mass production and reduces production costs. At the same time, it does not damage the original appearance design of the wall clock, meets the aesthetic needs of modern homes, and can be widely used in various smart wall clock products, promoting the upgrade of wall clocks from traditional timekeeping tools to smart home nodes. Detailed Implementation

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1

[0021] This embodiment provides a radar-sensing intelligent backlight control system for wall clocks, suitable for small to medium-sized wall clocks (diameter <30cm) and home use. It includes a radar sensing module, a main control module, an ambient light detection module, a backlight driving module, a backlight emission module, a power supply module, and a parameter configuration module. These modules are electrically connected via wires to collaboratively achieve fully intelligent control of the wall clock backlight. Details are as follows: The radar sensing module uses the RCWL-0516 model 24GHz millimeter-wave radar sensing module. Based on frequency-modulated continuous wave technology and the Doppler effect, this module integrates radar transmitting circuitry, radar receiving circuitry, and signal processing circuitry. The radar transmitting circuitry continuously emits 24GHz high-frequency millimeter-wave signals, which can penetrate the plastic material of the wall clock casing, eliminating the need for external installation and allowing it to be embedded inside the wall clock, thus maintaining the integrity of the wall clock's appearance. The radar receiving circuitry receives the echo signal reflected from the human body. The signal processing circuitry compares and analyzes the transmitted and reflected waves, resolving their frequency and phase differences to accurately identify the presence of the human body, the distance between the human body and the wall clock, and subtle human movements. The sensing signal is then transmitted to the main control module. The radar sensing module has a detection range of 0.5-5 meters, adjustable through parameter configuration. The main control module uses an STM32F103C8T6 microcontroller, a 32-bit microcontroller characterized by low power consumption, fast processing speed, and rich interfaces. It integrates data processing, logic judgment, and instruction output functions, meeting the needs of multi-module collaborative control. The main control module connects to the radar sensing module to receive its human body sensing signals; it connects to the ambient light detection module to receive its ambient light intensity data; it connects to the backlight driver module via a PWM output interface to output PWM control commands; it connects to the parameter configuration module to receive user-defined parameter commands; and it connects to the power supply module to obtain a stable power supply. In addition, the main control module has a built-in Flash storage unit, which can store parameters such as detection distance, backlight brightness level, and sleep delay set by the user through the parameter configuration module. These parameters are automatically loaded when the system is powered on next time, without the need for repeated settings. The ambient light detection module uses the BH1750 digital ambient light sensor, which has a measurement range of 0-65535 lux, high measurement accuracy, fast response speed, and low power consumption. It connects to the main control module and can directly output standard illuminance values ​​without additional A / D conversion, reducing signal interference. The ambient light detection module continuously detects the light intensity of the surrounding environment and transmits illuminance data to the main control module every 500ms, providing accurate data support for backlight brightness adjustment. This ensures that the backlight brightness is always adapted to the current environment, avoiding glare from strong light at night and energy waste during the day. The backlight driver module consists of a PWM signal generation circuit and a constant current drive circuit. The PWM signal generation circuit receives PWM control commands from the main control module, while the constant current drive circuit uses an AO3401 MOSFET as the driver chip, along with a current-limiting resistor, to achieve constant current drive functionality. The backlight driver module is connected to the main control module and the backlight emission module, receiving PWM control commands from the main control module. By adjusting the duty cycle of the PWM signal, it achieves precise stepless adjustment of the backlight brightness. Simultaneously, the constant current drive circuit ensures stable current through the LED chips, avoiding color temperature drift issues caused by traditional analog dimming, guaranteeing backlight color consistency, and improving visual comfort. The backlight module uses 12 soft-light LED beads (model: SMD 2835) arranged in a ring around the clock face. The LED beads have a rated voltage of 3.3V and a rated current of 20mA. They are low-power, long-life LED beads that emit a soft, warm white light with a color temperature of 3000K, avoiding strong light that may disturb the user's sleep at night. A precision light guide plate is placed below the LED beads. The light guide plate can be made of PMMA and is 2mm thick. It can evenly diffuse the light emitted by the LED beads across the entire clock face, avoiding glare from certain areas and ensuring uniform brightness throughout the clock face, thus improving readability and visual comfort. The power module adopts a dual AC / DC power supply design, including an AC power supply interface, a step-down regulator circuit, a lithium battery, and a low-power management circuit. The AC power supply interface can be connected to a household 220V AC power supply. The step-down regulator circuit uses LM1117-3.3 and LM1117-5.0 regulator chips to convert the 220V AC power supply into stable 3.3V and 5V DC voltages, respectively powering the radar sensing module, main control module, ambient light detection module, backlight driver module, and backlight emission module. The lithium battery is a 3.7V / 1000mAh rechargeable lithium battery, serving as a backup power source. It is connected to the step-down regulator circuit through a charging management chip (such as the TP4056 chip). Under normal AC power supply, the lithium battery is in a charging state. In the event of a sudden power outage, it automatically switches to lithium battery power to prevent system shutdown. The low-power management circuit is connected to the main control module and receives low-power control commands from the main control module. In the absence of users, it controls the radar sensing module and ambient light detection module to enter a low-power sleep state, reducing the overall power consumption of the system and extending the battery life. The parameter configuration module adopts a button design with three buttons: distance adjustment, brightness adjustment, and delay adjustment. The module connects to the main control module, allowing users to manually adjust system parameters. For example, pressing the distance adjustment button cycles through detection distances of 0.5 meters, 1 meter, 2 meters, and 3 meters; pressing the brightness adjustment button cycles through backlight brightness levels of low, medium, and high; and pressing the delay adjustment button cycles through sleep delay times of 10 seconds, 20 seconds, 30 seconds, and 60 seconds. After parameter adjustment, the main control module stores the parameters in the Flash memory, which is automatically loaded upon the next power-on.

[0022] Example 2

[0023] This embodiment provides another radar-sensing intelligent backlight control system for wall clocks, suitable for large-sized wall clocks (diameter ≥ 30cm) and office environments. It includes a radar sensing module, a main control module, an ambient light detection module, a backlight driver module, a backlight emission module, a power supply module, and a parameter configuration module. These modules are integrated and connected via a PCB board to collaboratively achieve fully intelligent control of the wall clock backlight. The difference between this embodiment and the first embodiment lies in the optimized module selection and scene adaptation adjustments; details are as follows: The radar sensing module uses a 24GHz millimeter-wave radar sensing module, model 24G-01. Based on Frequency Modulated Continuous Wave (FMCW) technology and the Doppler effect, this module incorporates a high-gain antenna and signal amplification circuit, continuously emitting 24GHz high-frequency millimeter-wave signals. These signals can penetrate the wooden or glass casing of the wall clock (with a thickness not exceeding 8mm) and are embedded in a pre-drilled mounting slot on the back of the clock, eliminating the need for external exposure and preserving the clock's appearance. This also enhances the sensing distance and sensitivity. The radar sensing module receives echo signals reflected from the human body and analyzes the frequency and phase differences between the transmitted and reflected waves through its internal signal processing circuitry. This allows for accurate identification of the human presence, the distance between the person and the wall clock, and subtle human movements. The detection range is 0.8-5 meters and can be adjusted via a parameter configuration module to suit the needs of long-distance time reading in office environments. Furthermore, it possesses anti-electromagnetic interference capabilities, avoiding interference from computers, printers, and other equipment in the office environment, thus improving sensing stability. The main control module uses the STM32L431RCT6 microcontroller, an ultra-low-power 32-bit microcontroller with fast processing speed, rich interfaces, and integrated data processing, logic judgment, and instruction output functions. It is suitable for long-term low-power operation and can meet the stable operation requirements of multi-module collaborative control and office scenarios. The main control module is connected to the radar sensing module to receive the human body sensing signal it outputs, connected to the ambient light detection module to receive the ambient light intensity data it outputs, connected to the backlight driver module to output PWM control instructions, connected to the parameter configuration module to receive user-set parameter instructions, and connected to the power supply module to obtain stable power supply. The control logic of the main control module is optimized based on the first embodiment to adapt to office scenarios: After the system is powered on, each module initializes, and the radar sensing module and ambient light detection module work continuously to collect data and transmit it to the main control module; the main control module determines whether the radar sensing module has detected the presence of a human body and the distance is within the preset range. If not, it controls the backlight driver module to turn off the backlight, and the system enters a deep low-power sleep state, waking up the radar sensing module every 15 seconds to perform a detection; if yes, it adjusts the backlight brightness according to the light intensity detected by the ambient light detection module through a preset algorithm: when the light intensity is ≤30 lux, the backlight brightness is adjusted to the highest; when 30 lux < light intensity ≤500 lux, the backlight brightness is adjusted to medium; when the light intensity >500 lux, the backlight brightness is adjusted to the lowest. If a human body is detected to have left or the distance exceeds the preset range, a sleep delay is initiated, with a preset delay of 60 seconds to adapt to the scenario of office workers leaving briefly. After the delay ends, the backlight is turned off, and the system enters a deep low-power state. The ambient light detection module uses the TSL2561 digital ambient light sensor, which has a measurement range of 0-40000 lux, high measurement accuracy, fast response speed, and automatic gain adjustment function. It can adapt to different lighting environments in office scenarios, such as strong light during the day and weak light at night. It connects to the main control module and directly outputs standard illuminance values ​​without the need for additional signal conversion, reducing signal interference. The ambient light detection module transmits illuminance data to the main control module every 300ms, providing precise support for the main control module to adjust the backlight brightness, ensuring clear and non-glaring readings under different lighting conditions in office scenarios, balancing practicality and visual comfort. The backlight driver module consists of a PWM signal generation circuit, a constant current drive circuit, and an overcurrent protection circuit. The PWM signal generation circuit receives PWM control commands from the main control module. The constant current drive circuit uses a TPS62085 chip as the driver chip, along with current-limiting resistors and filter capacitors, to achieve constant current drive and stable voltage output. The overcurrent protection circuit prevents damage to the LED beads from overcurrent, improving system reliability. The backlight driver module is connected to the main control module and the backlight emission module. The PWM signal duty cycle is adjustable from 0-100%, enabling precise stepless adjustment of backlight brightness. The constant current drive circuit ensures stable current through the LED beads, avoiding color temperature drift and guaranteeing backlight color consistency, suitable for long-term reading needs in office scenarios. The backlight module is compatible with large-size wall clocks and uses 24 soft-light LED beads (model: SMD 5050) arranged in a ring around the clock face. The LED beads have a rated voltage of 5V and a rated current of 30mA. They are low-power, high-brightness models that emit neutral white light at a color temperature of 4500K, suitable for the time reading needs of office scenarios. This ensures clarity without the warm light affecting work focus. A double-layer precision light guide plate made of PC material is set below the LED beads. The light guide plate is 3mm thick and can evenly diffuse the light emitted by the LED beads across the entire clock face, avoiding glare from strong local areas and ensuring uniform brightness throughout the large clock face, thus improving the time reading experience in office scenarios. The power module adopts a dual AC / DC power supply design, including an AC power supply interface, a step-down regulator circuit, a lithium battery, and a low-power management circuit. The AC power supply interface can connect to a 220V AC power supply in office environments. The step-down regulator circuit uses an MP2307 step-down chip and an AMS1117 regulator chip to convert the 220V AC power to stable 3.3V and 5V DC voltages, respectively powering the radar sensing module, main control module, ambient light detection module, backlight driver module, and backlight emission module. The lithium battery is a 3.7V / 2000mAh rechargeable lithium battery, serving as a backup power source. It is connected to the step-down regulator circuit via a TP4056 charging management chip. Under normal AC power supply, the lithium battery is in a charging state; in the event of a power outage, it automatically switches to lithium battery power to prevent system shutdown. The low-power management circuit is connected to the main control module and receives low-power control commands from the main control module. In unattended operation, it controls the radar sensing module and ambient light detection module to enter a deep low-power sleep state, reducing overall system power consumption and extending the lithium battery's battery life, adapting to the needs of long-term unattended operation in office scenarios. The parameter configuration module adopts a wireless remote control design, communicating with the main control module via Bluetooth. Users can adjust system parameters, including but not limited to radar detection distance (0.8m, 2m, 3m, and 5m options), backlight brightness levels (low, medium, high, and stepless adjustment options), and sleep delay time (30 seconds, 60 seconds, 90 seconds, and 120 seconds), adapting to the long-distance parameter adjustment needs in office scenarios. The parameter configuration module 7 features parameter memory and batch configuration functions, allowing the same parameters to be configured for wall clocks in multiple office areas simultaneously, improving ease of use.

[0024] A radar-sensing intelligent backlight control method for wall clocks, based on the radar-sensing intelligent backlight control system for wall clocks described in Embodiments 1 and 2, comprises the following steps: S1 System Initialization: After power-on, the main control module performs self-tests on each module, loads preset parameters, and the radar sensing module and ambient light detection module enter low-power monitoring state, while the backlight emitting module is in the off state. S2 Human Body Sensing Monitoring and Backlight Adjustment: The radar sensing module continuously scans the surrounding environment. When a human body is detected entering the preset detection range (and the micro-movement or stillness of the human body is identified), a human body presence signal is output to the main control module. If no human body is detected, the system maintains a low power consumption state and the backlight remains off. S3 Ambient Light Detection and Backlight Adjustment: After the main control module receives a signal indicating the presence of a human body, it triggers the ambient light detection module to collect the current ambient light intensity data. Based on a preset algorithm, the light intensity is divided into multiple levels, including dim: <50 lux, low light: 50-200 lux, normal: 200-1000 lux, and strong light: >1000 lux. Correspondingly, PWM control commands with different duty cycles are generated and sent to the backlight driver module. S4 Backlight Adjustment: The backlight module lights up and adjusts to the corresponding brightness according to the PWM command, while the main control module continuously receives signals from the radar sensing module. If the human body is within the detection range, the backlight maintains the current brightness. If the human body leaves the detection range, the main control module starts a sleep timer. After the timer reaches the preset delay, the backlight is turned off and the system returns to the low-power monitoring state.

[0025] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A radar-sensing intelligent backlight control system for wall clocks, characterized in that: It includes a radar sensing module, a main control module, an ambient light detection module, a backlight driving module, a backlight emission module, a power supply module, and a parameter configuration module; The radar sensing module is used to identify the presence of a human body, its distance from the clock, and micro-motion signals, providing parameters for backlight control. The main control module receives human body sensing signals from the radar sensing module and light intensity signals from the ambient light detection module, generates backlight control commands based on a preset algorithm and sends them to the backlight driver module; it also receives commands from the parameter configuration module to adjust the radar detection distance, backlight brightness level, sleep delay parameters, and stores the parameters. An ambient light detection module is used to detect the intensity of ambient light. The backlight driver module is used to receive instructions from the main control module, drive the backlight emission module to work, and achieve precise adjustment of backlight brightness. The backlight module is used to emit backlight, and includes multiple LEDs and a light guide plate, with the LEDs mounted on the light guide plate; The power supply module is used to supply power to each module; The parameter configuration module allows users to manually adjust system parameters; The main control module is electrically connected to the radar sensing module, the ambient light detection module, the backlight driving module, the backlight emitting module, and the parameter configuration module, respectively. The power supply module is electrically connected to the radar sensing module, the main control module, the ambient light detection module, the backlight driving module, the backlight emitting module, and the parameter configuration module, respectively.

2. The radar-sensing intelligent backlight control system for wall clocks according to claim 1, characterized in that: The radar sensing module uses a 24GHz millimeter-wave radar sensing module, which has a built-in radar transmitting circuit, radar receiving circuit and signal processing circuit, and the detection range can be adjusted from 0.5 to 5 meters.

3. The radar-sensing intelligent backlight control system for a wall clock according to claim 1, characterized in that: The main control module uses an STM32F103C8T6 microcontroller, which integrates data processing, logic judgment and instruction output functions, and has a built-in Flash storage unit for storing user-set parameters; the preset algorithm is: when a human body is detected and the distance is within the preset range, the backlight brightness is adjusted according to the ambient light intensity. When a human body is not present or is outside the preset range, the backlight is turned off after a preset delay and the system enters a low-power state.

4. The radar-sensing intelligent backlight control system for a wall clock according to claim 1, characterized in that: The ambient light detection module uses a digital ambient light sensor with a measurement range of 0-65535 lux and an operating current of ≤10μA.

5. The radar-sensing intelligent backlight control system for a wall clock according to claim 1, characterized in that: The backlight driving module adopts PWM dimming technology and consists of a PWM signal generation circuit and a constant current driving circuit. The constant current driving circuit uses an AO3401 field-effect transistor as the driving chip and a current-limiting resistor to achieve constant current driving. The duty cycle of the PWM signal is adjustable from 0 to 100%.

6. The radar-sensing intelligent backlight control system for a wall clock according to claim 1, characterized in that: The backlight module uses 8-24 soft-light LED beads arranged in a ring, with a rated voltage of 3.3V, a rated current of 20mA, a color temperature of 3000K, and a light guide plate made of PMMA with a thickness of 2mm.

7. The radar-sensing intelligent backlight control system for a wall clock according to claim 1, characterized in that: The power module adopts a dual AC / DC power supply design, can be connected to a 220V AC power supply, and has a built-in rechargeable lithium battery as a backup power supply; it integrates step-down voltage regulation and low power consumption management circuits.

8. The radar-sensing intelligent backlight control system for a wall clock according to claim 7, characterized in that: The step-down voltage regulator circuit uses LM1117-3.3 and LM1117-5.0 voltage regulator chips to output stable voltages of 3.3V and 5V; the lithium battery is a 3.7V / 1000mAh rechargeable lithium battery with a TP4056 charging management chip. The system power consumption in sleep mode is ≤50mW, and the lithium battery has a full charge life of ≥72 hours.

9. A radar-sensing intelligent backlight control system for a wall clock according to claim 1, characterized in that: The parameter configuration module includes buttons or a touch screen and a Bluetooth communication module. Parameters can be set via buttons or directly on the touch screen, or via a mobile app connected to the Bluetooth module, enabling remote parameter configuration and status monitoring. The parameters to be set include, but are not limited to, detection distance, backlight brightness, and sleep delay time.

10. A radar-sensing intelligent backlight control method for a wall clock, based on the radar-sensing intelligent backlight control system for a wall clock according to any one of claims 1-9, comprising the following steps: S1 System Initialization: After power-on, the main control module performs self-tests on each module, loads preset parameters, and the radar sensing module and ambient light detection module enter low-power monitoring state, while the backlight emitting module is in the off state. S2 Human Body Sensing Detection and Backlight Adjustment: The radar sensing module continuously scans the surrounding environment. When a human body is detected entering the preset detection range, a human body presence signal is output to the main control module. If no human body is detected, the system maintains a low power consumption state and the backlight remains off. S3 Ambient Light Detection and Backlight Adjustment: After the main control module receives a signal indicating the presence of a human body, it triggers the ambient light detection module to collect the current ambient light intensity data. Based on a preset algorithm, the light intensity is divided into multiple levels, and PWM control commands with different duty cycles are generated and sent to the backlight driver module. S4 Backlight Adjustment: The backlight module lights up and adjusts to the corresponding brightness according to the PWM command, while the main control module continuously receives signals from the radar sensing module. If the human body is within the detection range, the backlight maintains the current brightness. If the human body leaves the detection range, the main control module starts a sleep timer. After the timer reaches the preset delay, the backlight is turned off and the system returns to the low-power monitoring state.