Method and arrangement for detecting and identifying target objects

摘要

The use of radar devices for detecting and identifying target objects is based on the finding that the radar echo signals contain characteristic Doppler frequencies which are produced on moving parts of the propulsion units. A laser sensor operating in accordance with the radar principle, comprising a laser transmitter and an optical heterodyne receiver, detects characteristic surface vibrations of the target objects and derives from the laser echo signals, after frequency conversion and demodulation, low-frequency oscillations having the frequencies of the vibration spectrum, from which detection and identification results are determined by comparison with patterns of known target objects. <IMAGE>