Accession Number : ADD001484

Title :   Chirp Signal Apparatus.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON D C

Personal Author(s) : Rowlands,Richard

Report Date : 10 Sep 1974

Pagination or Media Count : 5

Abstract : The patented apparatus includes a hydrophone for sensing underwater sonar signals, a gain controlled amplifier receiving the hydrophone output, and a chirp signal detector for detecting chirp signals having an instaneous frequency which increases with time. The chirp detector is further described as including a specially clamped reed which is electromagnetically driven into vibration having an instantaneous frequency equivalent to that of the sensed chirp signal and having an instantaneous peak amplitude corresponding to a characteristic nonlinear frequency vibration amplitude response. The apparatus disclosed further includes threshold detector means responsive to reed vibration amplitude for indicating the reception of the chirp signal to utilization apparatus.

Descriptors :   *Detectors, *Patents, Signals, Underwater sound signals

Subject Categories : Acoustic Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE