DFRobot SEN0395 mmWave Radar Sensor (24GHz) for Human Presence Detection (9 m Range)

Unlike PIR sensors that detect moving heat sources, this 24GHz mmWave radar uses FMCW/CW modulation to detect phase shifts in reflected radio waves. This allows it to sense micro-movements (like breathing) and completely stationary human presence, providing reliable detection even when a person is sitting still or sleeping. It is also largely unaffected by environmental factors like temperature gradients or ambient light.

The module provides two primary output methods. First, a UART serial interface (default 115200 bps) outputs detailed JSON or string-formatted data packets containing target status, distance, and energy values. Second, a configurable GPIO pin can be set as a simple digital switch output (high/low) based on presence detection thresholds, useful for directly triggering relays or alarms without a microcontroller.

The sensor operates from a 3.6V to 5V DC power supply. Under typical operating conditions, it draws approximately 90mA. Ensure your power source can provide stable voltage within this range, especially when powering additional circuitry from the same supply, to maintain sensor accuracy and communication stability.

Yes, parameters like detection range thresholds, sensitivity, and hold time can be configured via serial commands sent to the module. This allows you to fine-tune the sensor for specific application scenarios, such as reducing false triggers in cluttered environments or setting a minimum detection distance to ignore nearby objects.

The module has a robust operating temperature range of -40°C to +85°C and is immune to interference from rain, snow, haze, dust, and light. However, the PCB itself is not conformally coated or housed in an IP-rated enclosure. For permanent outdoor installation, the module must be placed inside a suitable protective housing that is transparent to 24GHz radio waves, such as an ABS or polycarbonate enclosure.