Method of extracting target range and Doppler information from a Doppler- spread signal

摘要

A method of extracting target range and Doppler information from a Dopplepread signal is provided. An acoustic waveform is transmitted underwater and impinges upon a submerged Doppler-spread target. Doppler- spread sonar echoes resulting from the transmitted waveform are received and digitized. The received sonar echo is separated into its inphase and quadrature components thereby forming a complex vector function. A fourth- order cumulant spectrum is generated from the complex vector function based upon three time delays. In order to extract the range and Doppler information from the Doppler-spread signal, the first of the time delays is set equal to zero while the second and third time delays are set equal to one another.