Study on the characteristics of dolphins click signal

Dolphins have a strong ability of target identification in the ocean, how to use it has become a new field of exploration.It is mainly divided into three categories in the research of dolphin communication signals namely whistle, click and emergency signals. Dolphin Click sound is mainly used for target detection and recognition. In this paper, the research group designed a pool experiment to obtain the click signal when dolphin identify rubber bar, reef, aluminum bar and steel ball, and analyzes the signal form, frequency, spectrum change rule and other information from the perspective of time domain and time-frequency domain. The number of sine waves in click signal is analyzed when dolphins identify four kind of targets. We summarize six kinds of spectrum forms to classify the acquired acoustic signals, the probability of each spectrum form is analyzed and counted when dolphins detect and identify different targets.The results show that the click signal emitted by dolphins in target recognition is mainly one waveform click signal. The main energy of the frequency is concentrated at 0-200khz.