Showing papers on "Object detection published in 1968"

Electromagnetic moving object detection system utilizing a coaxial line resonator

Abstract: A continuous wave, electromagnetic moving object detection system which responds to impedance changes in the antenna circuit produced by motion of an object through the area protected by the system. Increased sensitivity for a given level of radiated power and isolation of the oscillator circuitry from the detuning effects of changes in the protection environment are achieved by utilizing a coaxial line resonator. Alarm means actuated by detection of the impedance changes are employed to give an electrical, visual and/or audible indication of the presence of a moving object within the protected area.