Low-power consumption indoor inductive intelligent partition control system

Abstract

The application discloses a low-power-consumption indoor induction intelligent partition control system, and aims to solve the limitation of the existing induction system, the system comprising a sensor module, a control module, a communication module and an execution module. The sensor module is composed of a photosensitive sensor, a temperature sensor, a pyroelectric sensor and a 24G millimeter wave radar sensor, and is used for detecting environmental conditions and preliminarily detecting the existence of human bodies. When the environmental conditions are good, the system does not start the human body existence detection; otherwise, the pyroelectric sensor first performs preliminary detection, and once a living body is found, the millimeter wave radar is triggered to perform accurate detection. The control module converts the detection result into a control signal and transmits the control signal to the execution module through Bluetooth, and is used for controlling facilities such as lighting, fans, air conditioners and the like. The application is suitable for occasions where the operation of facilities needs to be flexibly adjusted according to the actual use conditions of different areas, and has the characteristics of energy saving and environmental protection, low cost, easy deployment and the like.

Description

Technical Field

[0001] This invention relates to the field of smart home control system technology, and more particularly to a low-power indoor sensor-based intelligent zoning control system. Background Technology

[0002] With increasing societal focus on energy conservation and emission reduction, improving energy efficiency has become a crucial issue in the field of smart home control. Especially in public spaces such as classrooms and offices, traditional control methods struggle to accurately respond to changes in human activity across different areas, leading to widespread energy waste. Current presence sensing systems have the following limitations: 1) High energy consumption, requiring continuous system operation to detect activity; 2) Insufficient detection accuracy. When human activity is minimal, traditional sensors may fail to accurately identify a person's presence, causing lighting systems, fans, and air conditioning lights to remain off even when someone is present; 3) Lack of refined zone control, unable to adjust according to the actual usage in different areas of the same space, further contributing to energy waste; 4) Susceptibility to external environmental influences, generating false alarms when no one is present. Summary of the Invention

[0003] The purpose of this invention is to provide a low-power indoor sensor-based intelligent zoning control system, which realizes intelligent detection and zoning control of indoor human activities. It is especially suitable for occasions where the operation of facilities needs to be flexibly adjusted according to the actual use of different areas, such as classrooms and offices, and achieves effective energy saving in three aspects: system operation, regional energy saving, and unattended power outages.

[0004] To achieve the above objectives, the technical solution adopted by this invention is as follows: a low-power indoor sensing intelligent zoning control system, including a sensor module, a control module, a communication module, and an execution module. The control module converts the detection results of the sensor module into control signals and transmits them to the execution module through the communication module for controlling the operation of indoor facilities. The sensor module consists of a photosensitive sensor, a temperature sensor, a pyroelectric sensor, and a 24G millimeter-wave radar sensor. The photosensitive sensor and temperature sensor are used to detect the temperature and light conditions of the environment. The pyroelectric sensor is used to detect whether a living organism has entered the detection range and can distinguish between living organisms and other objects. The millimeter-wave radar sensor performs more accurate detection to determine the location and activity of human bodies.

[0005] Preferably, the sensor module is controlled in a hierarchical manner, divided into three levels. The first level sensor is a photosensitive sensor and a temperature sensor. The second level sensor is a pyroelectric sensor. The next level sensor is activated after the previous level sensor meets the conditions. The third level sensor is a 24G millimeter-wave radar sensor.

[0006] Preferably, the indoor area is 15m 2The system is divided into zones, with a set of sensor modules installed in each zone. The sensor modules are mounted on the side of the wall within the zone, and the millimeter-wave radar is tilted at a 30-60° angle perpendicular to the ground.

[0007] Preferably, the millimeter-wave radar sensor employs signal processing algorithms including direction of arrival (DOA) estimation, constant false alarm rate (CFAR) detection, clustering algorithm (DBSCAN), and state machine (SM).

[0008] Preferably, the CFAR detection technology employs a range-compensated adaptive signal-to-noise ratio (SNR) detection algorithm. Considering the characteristic that signal strength is inversely proportional to the fourth power of the target distance, the expected power of the same target at different ranges can be calculated based on this signal attenuation law. The expected power formula can be expressed as:

[0009]

[0010] Where P1 is the power corresponding to the known target distance R1, and P2 is the expected power at the same target distance R2.

[0011] Preferably, the DBSCAN clustering algorithm is used to process the point cloud data after CFAR and classify the point cloud into different regions. For each region of the same location, the clustered point cloud data is defined as N, and the preset threshold is T. When N>T, it is judged that there are people. When N≤T, it is judged that there are no people. Then, SM technology is used to manage the state changes of each detected target.

[0012] Preferably, the millimeter-wave radar antenna adopts a 2*2 element array design with a maximum gain of 12.81dB. The antenna elements are fed by a 50Ω feed line, and their resonant operating point is 24.15GHz. The antenna elements are connected through a T-type power divider. The antennas are arranged in a counter-current configuration. The power divider provides unequal amplitude feeding and 180° phase compensation on one side. The T-type power divider is chamfered to increase impedance matching.

[0013] Preferably, the communication module adopts an HC-05 Bluetooth module, which is used for wireless communication with the user's mobile device and for controlling the opening and closing of public equipment.

[0014] Preferably, the execution module has a built-in Bluetooth switch, central processing unit, control module, servo motor and button battery, and is directly attached to the existing switch in the place of use. The module can receive control signals from the communication module, decode them through the internal central processing unit, and then drive the servo motor through the internal control module to control the opening and closing of indoor facilities.

[0015] The technical effects of this invention are as follows:

[0016] This system achieves intelligent detection of human activity and efficient, refined control of facilities through a multi-level detection mechanism and precise zone control. Its main innovations are as follows: First, a compact antenna is designed, ensuring both low cost and miniaturization while meeting high-efficiency requirements. In system design, photosensors and temperature sensors are used to initially detect ambient light and temperature conditions. If preset favorable conditions are met, the presence sensing system remains inactive. If conditions are unfavorable, a pyroelectric sensor is used to distinguish living individuals from other objects. When a living individual is detected, a low-power millimeter-wave radar is activated for further detection, thus reducing power consumption. Next, in zone control, multiple millimeter-wave radar processing technologies are integrated to precisely detect the presence of people in indoor zones, reducing the impact of external temperature changes on detection results, improving detection accuracy, and further saving energy. Simultaneously, the communication module uses Bluetooth transmission, allowing wireless communication with users' mobile devices and external facilities for remote control and personalized settings. Notably, an easy-to-install switch with a built-in Bluetooth receiver is used. This switch can be directly attached to existing switches and receives control signals from the radar, thereby enabling zone control of lighting, fans, air conditioning, and other facilities. This innovative solution enables intelligent detection and zoned control of indoor human activity, and is especially suitable for occasions where facility operation needs to be flexibly adjusted according to the actual use of different areas, such as classrooms and offices, achieving effective energy conservation in three aspects: system operation, zone energy saving, and unattended power outages. Attached Figure Description

[0017] Figure 1 The diagram shown is a schematic diagram of the system module structure of the present invention;

[0018] Figure 2 The diagram shown is a schematic diagram of the partition detection of the present invention;

[0019] Figure 3 The diagram shown is a flowchart of the detection process of the present invention.

[0020] Figure 4 The diagram shown is a schematic of the BH1750 photosensitive sensor circuit of the present invention.

[0021] Figure 5 The diagram shown is a schematic of the circuit of the DS18B20 temperature sensor of the present invention.

[0022] Figure 6 The diagram shown is a hardware circuit diagram of the 24GHz millimeter-wave radar sensor of this invention.

[0023] Figure 7 The diagram shown is the EH plane radiation pattern of the 24GHz millimeter-wave radar antenna array of this invention.

[0024] Figure 8The diagram shown is of the S11 (return loss) of the 24GHz millimeter-wave radar antenna element of this invention.

[0025] Figure 9 The diagram shows the S11 (return loss diagram) of the 24GHz millimeter-wave radar antenna array of this invention.

[0026] Figure 10 The diagram shown is a flowchart of the millimeter-wave radar algorithm detection process of this invention.

[0027] Figure 11 The figure shown is a distance compensation SNR threshold diagram of the present invention. Detailed Implementation

[0028] The following will provide a clear and complete description of the concept, specific structure, and technical effects of the present invention in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, solution, and effects of the present invention. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other, and the same reference numerals used throughout the accompanying drawings indicate the same or similar parts.

[0029] This invention provides a low-power indoor sensing intelligent zoning control system, including a sensor module, a control module, a communication module, and an execution module. Please refer to the system module structure diagram below. Figure 1 The sensor module consists of a photosensor, a temperature sensor, a pyroelectric sensor module, and a millimeter-wave radar sensor. Please refer to the installation locations of the sensor module and the actuator module for details. Figure 2 The sensor module is mounted sideways on the wall, and the millimeter-wave radar should be tilted at a 30-60° angle perpendicular to the ground to achieve optimal coverage. One millimeter-wave radar in this system can be used for coverage of approximately 15m. 2 In locations where the area to be detected exceeds this size, the coverage can be extended by adding additional radar sensors.

[0030] Please refer to the system detection process of this invention. Figure 3 First, the same location is divided into multiple corresponding areas according to the distribution and number of facilities requiring control, such as... Figure 2 As shown, six zones within the same location are demonstrated. The shaded areas correspond to the on / off status of facilities such as lighting and air conditioning when people are present. These zones can be flexibly adjusted according to actual conditions. The system uses photosensitive and temperature sensors to perform preliminary detection of the surrounding environment. When the environmental conditions meet the preset requirements, i.e., sufficient light and suitable temperature, no further presence detection is performed. Otherwise, a pyroelectric sensor is used to detect the area in use first to distinguish between living beings and other objects. When a living being is detected, the millimeter-wave radar sensor is triggered to work. This reduces the working time of the millimeter-wave radar, thereby further reducing the system's energy consumption.

[0031] Specifically, the first step involves using a photosensor and a temperature sensor to detect the surrounding environment. The photosensor uses a BH1750 module, and its circuit diagram is shown below. Figure 4 As shown, VCC is connected to the power supply, GND is grounded, and the illuminance data of BH1750 is read via the I2C protocol. The preset standard value is 50 lx. The temperature sensor used is DS18B20, and its circuit diagram is shown below. Figure 5 As shown, VDD is connected to the power supply, DQ is connected to the control module to transmit data, and an external pull-up resistor is added. GND is grounded, and the temperature is preset to 26℃. When the light value is greater than the preset value and the temperature is lower than the preset value, it indicates that the environmental conditions are good, and other sensors are not activated at this time.

[0032] The second step involves activating the pyroelectric sensor when the light or temperature values ​​do not meet the preset requirements. The pyroelectric sensor is a W406Q PIR SENSOR. This sensor requires a 100NF capacitor connected to ground for its VDD input. It detects the presence of living organisms by detecting changes in infrared radiation. It is typically equipped with a Fresnel lens to aid focusing and infrared radiation. When a living organism is detected, the control module transmits this high-level signal to the millimeter-wave radar sensor, triggering radar operation.

[0033] The millimeter-wave radar sensor module uses the Skyrealy RC2412 chip, operates at a frequency of 24 GHz, and is equipped with a one-transmit, two-receive antenna. This invention designs the antenna and hardware circuitry. Please refer to the hardware circuit diagram of the millimeter-wave radar sensor module. Figure 6 Since the Skyrealy RC2412's ROM is only 10K bytes, which is insufficient for this project, the GD25WQ80E was chosen as additional storage. Considering the high manufacturing cost of the high-frequency board, the radar sensor module retains only the most essential components to ensure minimization; the remaining components are arranged on the lower-level low-frequency board. The radar sensor communicates with the low-frequency board via a serial port. The antenna array uses a 2×2 element design, with each antenna element fed by a 50Ω feed line and reaching resonance at 24.15GHz. The EH plane radiation pattern of the antenna array can be found in [reference needed]. Figure 7 .

[0034] To achieve system miniaturization and improve integration, the antenna elements are arranged in a counter-facing configuration and connected via a T-shaped power divider. The power divider design includes unequal amplitude feeding and a 180° phase compensation mechanism to ensure signal phase consistency throughout the array. Furthermore, to improve impedance matching and further optimize performance, the T-shaped power divider features beveled corners. This antenna array exhibits excellent matching characteristics in the 23.88-24.45 GHz frequency range, with the S11 parameter remaining below -10 dB across the entire bandwidth. Optimal matching is achieved at 24.14 GHz, with an S11 value as low as -22.34 dB. Please refer to the element S11 (return loss) diagram. Figure 8 Please refer to the S11 (return loss) diagram for the array. Figure 9 This excellent matching performance ensures efficient operation of the system within the specified frequency range, while the antenna array achieves a maximum gain of 12.81dB, fully meeting the system requirements.

[0035] The third step involves activating the millimeter-wave radar sensor module; please refer to the algorithm flow for details. Figure 10 First, a frequency-modulated continuous wave signal is sent to collect human body reflection signals in real time, resulting in two ADC data streams containing the target's spatial location information. This information is preprocessed, including 1DFFT and 2DFFT, with invalid values ​​removed during 2DFFT, followed by DOA estimation to generate a 3D point cloud to determine the human body's orientation relative to the sensor. To maintain stable detection performance in complex backgrounds, CFAR detection technology is employed. This technology automatically adjusts the detection threshold based on background noise levels, reducing interference caused by background noise.

[0036] To meet the requirements of intelligent zone control, further improve detection accuracy, and adapt to the need for human presence detection at different distances and angles, this radar algorithm incorporates a range-compensated adaptive signal-to-noise ratio (SNR) detection algorithm in its CFAR detection technology. Considering the characteristic that signal strength is inversely proportional to the fourth power of the target distance, the expected power of the same target at different ranges can be calculated based on this signal attenuation law. Thus, even at different distances, the system can maintain relatively consistent detection performance, ensuring accuracy and reliability throughout the intelligent zone control system. The expected power formula can be expressed as:

[0037]

[0038] Where P1 is the power corresponding to the known target distance R1, and P2 is the expected power at the same target distance R2. Please refer to the distance-compensated SNR threshold diagram. Figure 11In this example, when R1 is set to 4m, P1 is 11dB, and the range of R2 is set to [1,5]. For distances less than 1m, please refer to the data at 1m; and for distances greater than 5m, please refer to the data at 5m.

[0039] The fourth step, to distinguish individuals within different areas and reduce false detections, involves using the DBSCAN clustering algorithm to process the CFAR-processed point cloud data and categorize the point clouds into different areas. For each area within the same location, the clustered point cloud data is defined as N, with a preset threshold of T. When N > T, the area is considered occupied; when N ≤ T, it is considered unoccupied. Next, the SM (Signaling and Monitoring) technique is used to manage the state changes of each detected target, including entry, stay, departure, and delay, represented by 00, 01, 10, and 11 respectively, to describe the activity state of the human body within each zone.

[0040] The control module is a storage unit connected to the sensor. It uses 1 and 0 to represent the on and off states of each area facility. By default, when the radar sensor detects an entry, the control module sends a 1 command to the execution module via Bluetooth, at which point the radar enters the 01 state. When a person leaves the detection area, the control module sends a 0 command to the execution module via Bluetooth. Users can set the delay time via Bluetooth. Taking a 1-minute delay as an example, when the radar detects a person leaving, it will enter the delay state, while still keeping the facility on for 1 minute, before switching to the leaving state.

[0041] The control module, acting as a storage unit, is connected to the sensor module and is responsible for managing the on (1) and off (0) states of each detection area facility. By default, when the radar sensor detects someone entering the detection area, the control module sends a "1" command to the execution module via Bluetooth, at which point the radar enters the "01" state (staying state). When the person leaves the detection area, the control module sends a "0" command to the execution module via Bluetooth, and the radar enters the "10" state (leaving state).

[0042] Users can personalize the delay time D (in seconds) after leaving via Bluetooth communication. Let t be the current time, t leave To detect the time when a person leaves. When t < t leave +D, the radar is in state "11" (delay state); when t≥t leave When +D is applied, the radar is in state "10" (away state). For example, when the delay is set to 1 minute, once the radar detects that a person has left, it will enter state "11" (delay state). During this period, the facility remains on for 1 minute. After the delay ends, the radar state switches from "11" to "10" (away state), at which point the facility is turned off.

[0043] The execution module is a Bluetooth receiver switch that can be directly attached to the existing switch to receive signals from the control module, decode them, and then control the opening and closing of indoor facilities (lighting, fans, air conditioning, etc.).

[0044] Although the description of the invention has been quite detailed and particularly of several described embodiments, it is not intended to limit it to any of these details or embodiments or any particular embodiment, but should be considered as providing a broad possible interpretation of the claims by referring to the appended claims and taking into account the prior art, thereby effectively covering the intended scope of the invention. Furthermore, the invention has been described above with respect to embodiments foreseeable by the inventors in order to provide a useful description, and non-substantial modifications to the invention that have not yet been foreseen may still represent equivalent modifications.

[0045] The above description is merely a preferred embodiment of the present invention. The present invention is not limited to the above-described embodiments. Any embodiment that achieves the technical effects of the present invention using the same means should fall within the protection scope of the present invention. Within the protection scope of the present invention, various modifications and variations can be made to the technical solutions and / or implementation methods.

Claims

1. A low-power indoor sensor-based intelligent zoning control system, characterized in that, The system includes a sensor module, a control module, a communication module, and an execution module. The control module converts the detection results from the sensor module into control signals and transmits them to the execution module via the communication module to control the operation of indoor facilities. The sensor module consists of a photosensitive sensor, a temperature sensor, a pyroelectric sensor, and a 24G millimeter-wave radar sensor. The photosensitive and temperature sensors detect the ambient temperature and lighting conditions. The pyroelectric sensor detects whether a living organism has entered the detection range and can distinguish between living organisms and other objects. The millimeter-wave radar sensor performs more precise detection, determining the location and activity of human beings. The millimeter-wave radar sensor employs signal processing algorithms including direction-of-arrival estimation, constant false alarm rate detection, clustering algorithms, and state machines. In the constant false alarm rate detection technology, a range-compensated adaptive signal-to-noise ratio detection algorithm is used. Considering the characteristic that signal strength is inversely proportional to the fourth power of the target distance, the expected power of the same target at different ranges is calculated based on this signal attenuation law. The expected power formula is expressed as: in, It is the known target distance The corresponding power, Distance to the same target The expected power was determined by using the DBSCAN clustering algorithm to process the CFAR-processed point cloud data and classify the point clouds into different regions. For each region of the same location, the clustered point cloud data was defined as N, and the preset threshold was T. At that time, it was determined that someone was present. If the target is found to be unmanned, then SM technology is used to manage the state changes of each detected target.

2. The low-power indoor sensing intelligent zoning control system according to claim 1, characterized in that, The sensor module is hierarchically controlled, divided into three levels. The first level of sensors are a photosensitive sensor and a temperature sensor. The second level of sensors are pyroelectric sensors. The next level of sensors is activated when the conditions of the previous level sensors are met. The third level of sensors are 24G millimeter-wave radar sensors.

3. The low-power indoor sensing intelligent zoning control system according to claim 2, characterized in that, Indoors, according to 15m 2 The system is divided into zones, with a set of sensor modules installed in each zone. The sensor modules are mounted on the side of the wall within the zone, and the millimeter-wave radar is tilted at a 30-60° angle perpendicular to the ground.

4. The low-power indoor sensing intelligent zoning control system according to claim 1 or 2, characterized in that, The millimeter-wave radar antenna adopts a 2*2 element array design with a maximum gain of 12.81dB. The antenna elements are fed by 50Ω feed lines, and its resonant operating point is 24.15GHz. The antenna elements are connected through a T-type power divider. The antennas are arranged in a counter-current configuration. The power divider is fed with unequal amplitude and 180° phase compensation is performed on one side. The T-type power divider is chamfered to increase impedance matching.

5. The low-power indoor sensing intelligent zoning control system according to claim 1, characterized in that, The communication module uses an HC-05 Bluetooth module, which is used for wireless communication with the user's mobile device and for controlling the opening and closing of public facilities.

6. The low-power indoor sensing intelligent zoning control system according to claim 1, characterized in that, The execution module has a built-in Bluetooth switch, central processing unit, control module, servo motor and button battery. It is directly attached to the existing switch in the place of use. The module can receive control signals from the communication module, decode them through the internal central processing unit, and then drive the servo motor through the internal control module to control the opening and closing of indoor facilities.

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