Doppler-Tolerant Classification of Distributed Targets -- A Bionic Sonar

Sonar echo analysis that is not affected by relative motion between target, transmitter, and receiver is discussed. Motion-tolerant measurement and recognition of range-distributed targets involves: 1) a determination of the effects of range rate upon echoes from non-planar reflectors and 2) the derivation of a signal, filter bank, and target parameterization scheme that is insensitive to those effects. The appropriate system is derived, simulated with a computer, and tested with actual echoes from various targets. The system's signals and filters are very similar to those found in biological sonars.