HB100 microwave modules is the use of Doppler radar (Doppler Radar) design principles of the microwave moving object detector, mainly used in automatic door control switch, security systems, ATM cash dispenser automatic recording control system, automatic train signals, etc. places.
HB100 10.525GHz standard microwave Doppler radar detector, the detection method in comparison with other detection method has the following advantages: 1, non-contact probe; 2, independent of temperature, humidity, noise, air, dust, light other effects, suitable for harsh environments; 3, anti-RF interference ability; 4, the output power is small, constitute a hazard to humans; 5, distance: detection range over 20 meters.
Doppler principle Introduction: Doppler theory based on time, when radio waves hit an object in the process of moving the wave is reflected, the frequency of the reflected wave will move across the state with an object is changed. If the touch position of the object radio wave is fixed, the frequency of the reflected wave and the transmitted wave frequency should be equal. If the object moves in the direction of transmission, the reflected wave will be compressed, that will increase the frequency of the reflected wave; conversely the frequency of the wave will be reflected decreases.
According to the principle of the Doppler microwave detectors designed by the FET source media DRO microwave oscillation (10.525GHz), power splitter, transmitting antenna, receiving antenna, mixers, detectors and other circuit (Figure 2). Outwardly directed microwave transmit antennas, when the object is encountered and the reflected wave received by the receiving antenna, a mixer and then to the oscillation mixed at low-frequency signal after detection of the reaction speed of moving objects.