System for collecting and processing data relating to moving bodies

摘要

An ultrasonic wave signal having its frequency varied continuously is transmitted from an ultrasonic wave transmitter toward a moving body. The wave reflected from the moving body is received by an ultrasonic wave receiver, and the resulting signal is frequency-demodulated to obtain a signal representing a frequency variation. A signal representing the feature of the moving body is produced with use of a signal representing the frequency variation of the transmitted ultrasonic wave and the signal representing the frequency variation of the received ultrasonic wave.