This economical and highly sensitive motion detection module uses the doppler effect to detect motion. Unlike the PIR sensor, this sensor is not that easy to fool. At a frequency of 5.8 GHz, signals are transmitted in 360 degrees, which are reflected back to this module. If the reflected signals deviate, this is immediately detected, this sensor can even detect movement behind (small) objects!
This module has 1 (digital) output which gives a voltage of 3.3V as output. The time that the signal is kept high after detection can be set with resistor R6 (on the back), without resistor this is 30 seconds. With a resistance between 1K and 250K, this delay can be set to 1 to 100 and seconds. By replacing the resistor R9, the sensitivity / detection distance can be set (10k - 100k).