Microwave detectors are devices that sense microwave radiation, which is a type of electromagnetic wave. They are commonly used in various applications, including security systems, motion detection, and radar technology. These detectors can identify the presence of objects or movement by measuring changes in microwave signals. The technology behind microwave detectors often involves the use of transistors or diodes that respond to microwave frequencies. When an object enters the detection zone, it alters the microwave signals, allowing the detector to trigger an alert or activate a system. This makes them valuable in both commercial and residential settings for safety and automation.