Energy Saving Low Cost Autodyne Short-Range Motion Sensor

The design and operation of an autodyne proximity sensor is considered. The autodyne system generator is constructed using a microstrip antenna as an open oscillation system of the device. At two points, the microstrip antenna is connected to the source and the source of the field-effect transistor. The central part of the microstrip antenna is connected to the common wire. The connection of the transistor and microstrip antenna is equivalent to the Hartley generator system (inductive three-point). In the drain circuit of the FET, the useful signal of the motion sensor is picked up. The motion sensor has a certain ease of implementation, while it allows registering moving objects at a distance of several tens of meters.