Pat.#5361070: Ultra-wideband radar motion sensor
INVENTORS: McEwan; Thomas E., Livermore, CA
ASSIGNEES: Regents of the University of California, Oakland, CA
ISSUED: Nov. 1, 1994
FILED: Apr. 12, 1993
ABSTRACT: A motion sensor is based on ultra-wideband (UWB) radar. UWB radar range is determined by a pulse-echo interval. For motion detection, the sensors operate by staring at a fixed range and then sensing any change in the averaged radar reflectivity at that range. A sampling gate is opened at a fixed delay after the emission of a transmit pulse. The resultant sampling gate output is averaged over repeated pulses. Changes in the averaged sampling gate output represent changes in the radar reflectivity at a particular range, and thus motion.