Method of formation of channels for a sonar, in particular for a towed-array sonar
US5058081A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 14, 1990 |
| Grant date | Oct 15, 1991 |
| Priority date | — |
| Expiry date | Sep 14, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K11/346
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a method of formation of channels for a sonar, after having sampled at a frequency T=1/4f.sub.0 (where f.sub.0 is the receiving center frequency of the sonar) the signals from the hydrophones of the sonar and having translated them to baseband, the signals thus translated are subsampled with a period T.sub.SE =kT (wherein k is an integer) substantially equal to 1.25 B, where B is the reception bandwidth of the sonar. A first set of signals is subsampled at identical times to form a frontal sector. Two further sets of signals are subsampled with delays between the signals from two adjacent hydrophones equal to T, which determines two side sectors adjacent to the frontal sector. The subsampled signals are then transmitted serially by the towing cable of the sonar device towed array and are processed in FFT circuits which allow to form in each sector a set of channels covering the sector. This allows to considerably reduce the data transmission rate between the towed portion of the sonar and the portion located in the towing ship.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.