Passive method for estimating state variables of a moving target radiating sound pulses into water

摘要

A passive method for estimating state variables such as range, speed, course and/or transmitting frequency of a moving target radiating sound pulses into water, from a receiver remote from the target is specified in which, for the purpose of reliable and fast estimation of the unknown state variables of the target, an echo generated by the sound pulses is detected in at least one selective receiving direction not aiming at the target, the Doppler frequencies occuring in the echo are detected and the state variables are determined by means of the Doppler echo frequencies. In this method, the Doppler echo frequencies are preferably obtained from the frequency spectra of the echo signals and acquired in correlation with the direction of reception and time of reception.