System Modeling And Analysis For Human Echolocation

Echolocation is a basic cognitive ability of human,and everyone has the potential to perceive the surrounding environment by echo.The research of human echolocation not only allows people to have a better understanding of their basic cognitive ability,but also can propose a new kind of environment-aware signal processing method,which can provide a theoretical basis and technical support for the development of portable echolocation device.Based on the psychology,physiology and anatomy,this paper focuses on the biological mechanism and signal processing mechanism of human echolocation.A complete model of human echolocation system is constructed,and several typical perceived scenes are simulated and analyzed.The main work of the paper can be summarized as follows:1)The mechanism of acoustic backscatter is studied,and the mathematical model of target sound signal is constructed.The correctness of the model is verified by comparing the signal of the target model with the signal collected by the experimental system.2)The physiological structure of the human auditory system and the function of its parts in the process of sound propagation and perception were studied.The mathematic model of the outer middle ear,the basement membrane,the inner hair cell-auditory nerve and the auditory center are realized,which are connected up to build a complete system of auditory system.The output signal of each module is simulated.3)The target modeling module and the auditory system module are cascaded to construct a complete human auditory system model,and the simulation of each part of the model is carried out.4)Aiming at three typical sensing scenes: distance detection,direction orientation and shape recognition,the signals from target modeling and collecting through the experimental system are respectively used as the input of the human auditory system model,and the output signal of the system model is analyzed.The signal characteristics are extracted by the two methods of pitch perception model and neuron release rate.The measurement of the target distance and direction,and the perception and recognition of the shape are realized.