METHOD AND APPARATUS FOR DETERMINING A FREQUENCY LINE PATTERN WITHIN AT LEAST ONE AMPLITUDE SPECTRUM TYPE

摘要

The invention relates to a method for determining a frequency line pattern within at least one amplitude spectrum that is produced from audible signals that have been radiated by at least one detected vehicle and received by means of a sonar installation. First of all, a predetermined number of frequency lines in the or each amplitude spectrum are selected and are sorted in order of decreasing amplitude magnitude and are selected using a threshold value that ensures that a predetermined suitable number is not exceeded. Following stipulation of a plurality of threshold values, frequency lines that have been selected taking account of at least one threshold value are compared with one another. The line pairs formed by the comparison are used to determine preliminary frequency line sets with an associated fundamental frequency that are rated on the basis of their identifiable structures. An exclusion method is used to form the final frequency line sets, taking account of a rating that is dependent on the sequence, the number, the density, the amplitude and the fundamental frequency of the frequency lines. It is then possible to find strong single lines that the spectrum may contain. For each detected vehicle, it is therefore possible to assign a target-oriented frequency line pattern that can be used to classify the vehicle. The invention also relates to an appropriate apparatus for carrying out the method according to the invention.