Research On Acoustic Detection And Location Technology Of Aircraft

In recent years, the emergence of some invisible wars in partial wars and the modernization of low-level weaponry and equipment have posed a threat to the traditional active radar systems.Passive sound detection technology, as the auxiliary detection and detection method of radar systems, has high positioning system accuracy and its own hidden high ,low cost. Therefore, it is necessary to study the passive acoustic detection technology.In this paper, the passive acoustic detection technology as the center for a certain amount of research, research content of passive voice recognition and passive acoustic positioning in two parts. Firstly, the background significance of the passive sound detection and the research status at home and abroad are introduced. Then the basic theory research of passive sound detection is carried out, including the propagation characteristics of the acoustic signal in the air and the generation mechanism of the aircraft acoustic signal. In the passive voice recognition part, the time-domain feature parameters and the frequency-domain feature parameters are extracted respectively from the acoustic signals of the measured four-rotor aircraft. The traditional classifier and BP neural network based on the DTW algorithm are established. Two classifiers are identified by these two classifiers The experiment of the recognition of the aircraft's acoustic signals is carried out. In the passive acoustic localization part, the array algorithm and time delay estimation algorithm of passive acoustic detection are deeply studied. The array model of five-element cross array is used to detect the acoustic signals of the aircraft. The error analysis is also used. In addition,the LMS adaptive time delay estimation method is adopted to simulate the delay estimation algorithm. Finally, a five-element cross array is used to locate the four-rotor aircraft.The experimental results show that the performance of BP neural network is higher than that of traditional DTW classifier for aircraft sound signal recognition. For the passive sound localization of aircraft, the positioning method of time delay estimation algorithm and array positioning algorithm are combined. For the 3m five-element cross array, the four-rotor vehicle near the sound field is located in the hovering state. The positioning error meets the requirements of the positioning accuracy in the near-sound field range, which verifies the feasibility of this positioning method in the near-sound field.