In a modern radar system, both recorded data and recorded intelligence information can be used together with data fusion output information to exactly identify or classify target type. Different techniques and strategies can be used to combine information from sensor system. In this technique of target classification, the difference in tone of various target type is utilized as heard by the operator. The different type of target generates a specific audio signal, which is heard by Ground Surveillance Radar operator via head phone. From audio signal, feature extraction has been carried out as a first step in order to uniquely identify audio tone of one target type from another, i.e., Heavy Vehicle to Light Vehicle, Group of men to Crawling men. Subsequently, fuzzy membership function is set to reflect the physical limits stored in the knowledge database for accurate identification of target audio tone type. The entire process of feature extraction and fuzzy logic has been done in MATLAB. The main aim of the paper is to study Digital Audio Processing Techniques and its applications in Ground Surveillance Radar.