Ultra-wide-band observing systems have not yet been created. However, theoretical advantages of sonar systems adapting to changes of hydrophysical conditions seem to be clearly visible in the study of marine mammalian sonar. Therefore, technical equipment for a broadband recording system under long-term laboratory experience is necessary. It makes possible studying the mobile broadband sonar using accurate biophysical and appropriate techniques that limiting the animal’s mobility during echolocation. The paper provides a number of methodological solutions for conducting an experiment on dolphins, which makes possible studying the noise immunity and secrecy of a natural sonar, and subsequently conduct comparative tests with technical analogues. Based on the presented methods, comparative estimates of echolocation signals belonging to various species of marine mammals will be obtained, and a database of biological signals will be formed — the search, tracking and recognition of underwater objects in difficult conditions of natural and artificial acoustic noise.