Computational Neuroscience In The Biological Sonar

The requirements of ocean development and anti—submarine warfare is the mainmotivation of sonar technology study, and the opportunities and the challenges facingsonar technology is coming in 21st century. Some subject, correlated or similar, iscoming out certain new conception, and these disciplines are various. Then more andmore people get to study the biosonar system. This paper simulates this system basedon method of neural computation, using a neuron as the basic unit. Apply code ofsingle neuron principle to study, we use pulse signal instead of outside signal to inputa neuron, then we extract the string of symbols contained in output pulse string. Afterthat, we use the symbols to express the out signal, and find the relationship betweenstring of symbols and outside information to to achieve the identification objective ofinformation. Above method is based on the theory of Circle maps and order space.Based on the above method and theory, this paper contains following: usingcomputer simulink to study functions of biosonar system, containing Echolocation,Doppler effect, measuring of anglar rate and noise cleanse. Echolocation is based onmeasuring the interaural time defference (ITD). Biosonar orientate the objective to thecorresponding couple curves related ITD. Then we get the Echolocation mechanismby analying the relation between output pulse string of symbols and ITD. Dealingwith the Doppler effect is based on the principle that the retrieved sound frequencyfollows the relative velocity. We attain the mechanism of judging the relative velocityby analying the relation between retrieved sound frequency and output pulse'ssymbols. In measuring the anglar rate, we use interaural frequency defference (IFD)to express the anglar rate because of perfect linear relationship between them. Thenwe get the mechanism of measuring anglar rate by study the relation between theoutput pulse symbols and the IFD. In the section of noise cleaning, we divide thenoise into internal noise and external noise, and study them respectively. Then, we getsome possible mechanism of noise cleaning in biosonar system.