Sensor array acoustic detection system
US3979712A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 5, 1971 |
| Grant date | Sep 7, 1976 |
| Priority date | — |
| Expiry date | Nov 5, 1991 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S367/901
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An acoustic detection system comprising two arrays of omnidirectional sensors or hydrophones wherein the sensors in each array are disposed along a curved line, such as an arc of a cylindrical surface. Accordingly an acoustic signal or wavefront propagating along any vector within the arc is registered by the respective sensors as phase lags determined by the locations thereof. The respective sensor output signals are each connected to a preselected electrical delay circuit such that the registered phase lags are further increased. The delayed sensor signals are then summed for each array, forming two directional beams and the signal sum for each array is then connected to identical narrow bandpass filters. The output of each filter is fed to a hard limiter, then to a differentiator and the output signals of the differentiators control a bistable flip-flop producing a pulse train where the width of each pulse corresponds to the phase lag difference between the beam signals. The pulse widths are then sorted into discrete bins of phase in a coincidence processor and read out when any one bin registers a number of pulses exceeding a predetermined number.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.