Highlight model of echoes from sonar targets

I.IntroductionTheecho-rangingapproachistheonlycffectiveapproachfordetectionandidentifi-cationofunderwatertargetifitisasilcntobkct.Echoformationisaphysicalprocessinwhichthetargetisexcitcdbyincidentwavc.Byechothecharactcristicinformationsoftargethavebcencarricd.Suchinformationsarejustfundamentalsofdetectionandiden-hficationappliedbyactivesonars.Classificationandidentificationareimportantdevelopmentsofreccntsonarsin-c1udingthehomersoftorpedocs.Thisneedsadecpunderstandingrcferredtoechobe-haviors…

Highlight model of echoes from sonar targets

This paper prcscnts a practical model of echoes for sonar engineering. Based on that the sonar systems usually use high frequency band-limited signals, the transfer function is appropriatc to characterize the target. At high frequencics, all echo components such as the specular reflected waves, the corner waves and the various clastic scattering waves can be thought of the returns from some equivalent scattering centres or highlights. The whole target is characterizcd by a group of the highlight in space.In this paper a general expression of the transfer function of the highlight is derived, which includes the amplitude factor, thc time delay and the phase jump. A determined parameter group provides a concrete target model.Simulation of the echo waveform can also be performed using the prescnted model.