SMART PRESENCE SENSOR SOLUTION USING RADAR
The radar-based human presence detection sensor is becoming an advanced and valuable technology in modern life. Smart presence sensors are widely used in various fields, such as smart buildings, devices that automatically adjust lighting, air conditioning, or open doors when detecting a person nearby, providing convenience and energy savings. Security systems also use radar sensors for monitoring and intrusion detection. Additionally, presence sensors are used in medical devices for patient monitoring, in vehicles for safe driving assistance, and in smart home applications to improve efficiency and convenience.
Recognizing the importance of this technology, EPI Vietnam offers an advanced human presence sensor solution designed to detect human presence through radar waves. The device uses a high-sensitivity 24GHz human presence sensor module. The working principle of the device involves using continuously modulated microwave signals (FMCW) to detect human targets within a defined space, combined with radar signal processing algorithms to identify human bodies in both motion and stationary states, providing accurate results in real-time. The product can detect human presence within a range of up to 6 meters.
Notably, this device can detect humans even when they are not moving, through heartbeat and breathing. It features smart connectivity via IOS app, Bluetooth, etc. By using electronic components from distributors like Toshiba, Holtek, Hongfa, and Hilink, EPI Vietnam is confident in providing customers with a smart, accurate, and energy-saving presence detection sensor solution.
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Specifications:
- Input voltage: 220Vac
- Microwave frequency: 24GHz
- Detection range: 0-6 meters
- Connectivity via IOS app, BLE
- Debug via Tool and UART
- Sensor angle: 60 degrees
Advantages:
- Smart, convenient
- Energy-saving for households
- Wide detection range
- Ability to detect accurately even when there is no movement
Applications:
- Control lights, fans, doors, etc. in the household
Main components used in the circuit:
1. HT66F0021-8SOP – Holtek
Specifications:
- Operating voltage: 1.8V to 5.5V
- Flash program memory: 1K×14 to 2K×14
- RAM data memory: 64×8
- Emulated EEPROM memory: 32×14
- A/D converter: 4 channels, 10 bits
- Output: PWM
- Oscillation frequency: 32kHz
- Package: 8-SOP
Learn more: HT66F0021-8SOP
2. Radar Sensor – HLK-LD2410B-P – Hilink
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Specifications:
- Small size, just like the tip of a pencil: 7mm * 35mm
- Frequency: 24GHz
- Supports debugging via tool app
- Supports connection to the app for debugging via Bluetooth
- Detection range: 6m
- Capable of detecting motion, heartbeats, and breathing
- Has 8 threshold levels (values from 0-100), each level separated by 0.75m
- Can connect to IOS app via BLE to retrieve data
Learn more: HLK-LD2410B-P
3. Relay – HF32FV-G/5-HSLTF(590) – Hongfa
Specifications:
- Switching capacity: 10A
- Coil voltage: 5V
- Dielectric voltage: 4kV (between coil and contacts)
- Contact configuration: 1 Form A (SPST-NO)
- Operating temperature: -40°C to +85°C
- Enclosure material: Sealed plastic, flow-resistant
- Insulation system: UL Class F
- Dimensions: 19.0mm x 15.5mm x 15.0mm
Learn more: HF32FV-G/5-HSLTF(590)
4. LDO – TAR5S50 – Toshiba
Specifications:
Block diagram
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