Accession Number : ADD015300

Title :   Method of Extracting Target Range and Doppler Information from a Doppler-Spread Signal.

Descriptive Note : Patent, Filed 20 May 91, patented 25 Feb 92,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Dwyer, Roger F

Report Date : 25 Feb 1992

Pagination or Media Count : 12

Abstract : A method of extracting target range and Doppler information from a Doppler-spread 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.

Descriptors :   *PATENTS, *TARGET POSITION INDICATORS, *DOPPLER SONAR, *UNDERWATER ACOUSTICS, ACOUSTICS, DELAY, SONAR ECHOES, TARGETS, TIME, UNDERWATER, WAVEFORMS, VECTOR ANALYSIS

Subject Categories : Acoustic Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE