Multifunction Human Detection And Weather Monitoring IoT Radar System

The Multifunction Human Detection And Weather Monitoring IoT Radar System operates by combining microwave motion sensing, ambient light detection, and smart connectivity into a single hardware architecture built around the IndusBoard Coin. At the core of the motion-sensing subsystem is the RCWL-0516 microwave radar module, which utilizes the Doppler effect to detect the presence and movement of humans through emitted and reflected electromagnetic waves. Unlike traditional passive infrared (PIR) sensors that rely solely on body heat, this radar module can penetrate non-metallic barriers, ensuring reliable motion detection within the target environment. Simultaneously, an LDR (Light Dependent Resistor) monitors ambient light levels, allowing the system to differentiate between day and night conditions. To manage connected equipment, the circuit integrates a VO2223A optotriac driven in conjunction with a 120Ω resistor and a 100Ω SMD resistor. The optotriac provides complete galvanic isolation between the low-voltage microcontroller logic on the IndusBoard and high-voltage AC mains circuits, protecting the control electronics from power surges. The 100nF capacitor is strategically placed for power supply decoupling and noise filtering, ensuring stable operation across all active modules. Interfacing the various peripheral boards and power rails is handled reliably through DB301V-3.5-2P-GN terminal connectors and an FPC connector. When the RCWL-0516 detects human presence and the LDR confirms low ambient light, the IndusBoard processes these sensor inputs and triggers the optotriac to securely switch external AC loads, while simultaneously transmitting real-time operational status data over Wi-Fi for remote IoT monitoring and wireless control.