US4954996A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Navigation sonar system dockside simulator
Assignee: Unisys Corp
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Filing: 1989-05-15
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Granted: 1990-09-04
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Expires: 2009-05-15
Abstract
Abstract A simulator of bottom return signals for a sonar system on a moving ship generates pulsed frequency modulated signals to simulate ocean bottom returns. Signals from the sonar transmitter are stretched in accordance with a postulated bottom configuration and applied to the frequency modulators to provide frequency modulated signals for the duration of the stretched pulses. Noise is simulated with the addition of an appropriate sinusoidal signal to each pulsed frequency modulated signal.
Inventors
- 👤 Luciano Fazzolari
- 👤 Frank P. Giattini
- 👤 Anthony L. Scoca
- 👤 Eugene C. Zavacki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:18
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/52; G01S7/52004
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
83 words
An apparatus for simulating sonar signals for a sonar navigation system on board a ship comprising: means for providing pulses simulating returned transmitted sonar pulses stretched in accordance with water bottom scattering; means coupled to said sonar pulses means for providing phase shifts to said sonar pulses that are respectively representative of a predetermined velocity of said ship, thereby providing pulses phase shifted sonar signals; and means for coupling said pulsed phase shifted sonar signals to processing channels of said sonar navigation system.
Claim 2
Independent Claim
83 words
An apparatus for simulating sonar signals for a sonar navigation system on board a ship comprising: means for providing pulses simulating returned transmitted sonar pulses stretched in accordance with water bottom scattering; means coupled to said sonar pulses means for providing phase shifts to said sonar pulses that are respectively representative of a predetermined velocity of said ship, thereby providing pulses phase shifted sonar signals; and means for coupling said pulsed phase shifted sonar signals to processing channels of said sonar navigation system.
Claim 3
Dependent Claim
61 words
A sonar signal simulator in accordance with claim 1 wherein said sonar pulses means includes: means for providing transmitted sonar pulses; means for sampling said transmitted sonar pulses; means coupled to said sampling melans for storing samples of said transmitted sonar pulses; and means coupled to said storing means for stretching said sonar pulses in accordance with predetermined water bottom characteristics.
Claim 4
Dependent Claim
41 words
A sonar signals simulator in accordance with claim 1 wherein said phase shifts means comprises a plurality of frequency modulated signal generators, each frequency modulating a predetermined signal at respective frequency deviations and deviation rates, thereby providing pulse frequency modulated signals.
Claim 5
Dependent Claim
22 words
A sonar signals simulator in accordance with claim 3 further including means for adding simulated noise to said pulse frequency modulated signals.
Claim 6
Dependent Claim
21 words
A sonar signals simulator in accordance with claim 4 wherein said noise means provides a sinusoidal signal at a predetermined frequency.
Claim 7
Dependent Claim
47 words
A sonar signals simulator in accordance with claim 4 further including means coupled to said adding means for distributing said pulsed frequency modulated signals with added noise to hydrophone channels of a sonar system to present simulated water bottom return signals representative of near zero knot velocity.
References Cited (Backward Citations)
US4168582A
Cited
US4626217A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-09-03 | 1994-03-05 | 1994-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-03 | 1998-03-05 | 1998-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-09-03 | 2002-03-05 | 2002-09-04 | $7700.00 | Window Closed / Lapsed |