US3789354A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Passive holography system
Assignee: United States Department of the Navy
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Filing: 1972-11-21
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Granted: 1974-01-29
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Expires: 1992-11-21
Abstract
Abstract The disclosure deals with a passive holography system for imaging remotely generated coherent acoustical signal source thru the techniques of phase locking a locally controlled, voltage controlled oscillator to the signal and at the same time displaying those signals so that an acoustical spectrum can be sampled and recorded until a desired signal is identified and then a second phase-locked-loop circuit is controlled to automatically track the received incoming signal and generate a reference signal which is coherent with the received signal and which is used by the holographic system to image the source of the received signal.
Inventors
- 👤 R Sternberg
- 👤 R Koppelmann
- 👤 R Mill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 04:48
CPC Classifications
G; G01; G01H; G01H9/00; G01H9/002; G03; G03H; G03H3/00
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
217 words
A passive Holography system comprising; a. an input circuit for receiving coherent remotely generated acoustical signals and generating output signals therefrom; b. a first phase-locked-loop circuit coupled to receive said output signals from said input circuit; c. a second phase-locked-loop circuit coupled to the signal from the said first phase-locked-loop to provide a 90* phase shift; d. a multiplier circuit coupled to the output of said second phase-locked-loop circuit and to said input circuit to provide an amplitude modulated signal that represents the received signal at the frequency set by said first phase-locked-loop; e. a first low pass filter coupled to receive the output of said multiplier circuit to filter out noise components; f. a third phase-locked-loop circuit coupled to receive a signal from said second phase-lokced-loop circuit for generating an output signal that is a frequency multiple of said acoustical signal; g. a switching system having manual and automatic positions for providing two modes of operation for said system coupled to said first and said second phase-locked-loop circuits; h. an X-Y recorder coupled to said switching circuit; i. a gate circuit coupled to said X-Y recorder, said gate circuit coupled to receive said amplitude modulated output signal from said multiplier circuit; and, j. means for coupling the output of said first phase-locked-loop to said gate circuit.
Claim 2
Dependent Claim
217 words
A passive Holography system comprising; a. an input circuit for receiving coherent remotely generated acoustical signals and generating output signals therefrom; b. a first phase-locked-loop circuit coupled to receive said output signals from said input circuit; c. a second phase-locked-loop circuit coupled to the signal from the said first phase-locked-loop to provide a 90* phase shift; d. a multiplier circuit coupled to the output of said second phase-locked-loop circuit and to said input circuit to provide an amplitude modulated signal that represents the received signal at the frequency set by said first phase-locked-loop; e. a first low pass filter coupled to receive the output of said multiplier circuit to filter out noise components; f. a third phase-locked-loop circuit coupled to receive a signal from said second phase-lokced-loop circuit for generating an output signal that is a frequency multiple of said acoustical signal; g. a switching system having manual and automatic positions for providing two modes of operation for said system coupled to said first and said second phase-locked-loop circuits; h. an X-Y recorder coupled to said switching circuit; i. a gate circuit coupled to said X-Y recorder, said gate circuit coupled to receive said amplitude modulated output signal from said multiplier circuit; and, j. means for coupling the output of said first phase-locked-loop to said gate circuit.
Claim 3
Dependent Claim
110 words
The improved passive holography system of claim 1 wherein said first phase-locked-loop circuit includes an input phase comparator circuit, a low pass filter, a direct current amplifier, a voltage controlled oscillator in which said phase comparator receives a signal from said input circuit and couples it thru said second low pass filter to said direct current amplifier that develops an error signal which is utilized to drive the voltage controlled oscillator to change the frequency output of said voltage controlled oscillator in a direction to bring the oscillator to the same frequency as the signal from the input system, said output of said oscillator is coupled to said phase comparator.
Claim 4
Dependent Claim
20 words
The system of claim 2 wherein said second phase-locked-loop circuit has substantially the same configuration as said first phase-locked-loop circuit.
Claim 5
Dependent Claim
43 words
The system of claim 3 wherein there is provided a third phase-locked-loop circuit coupled to receive the output signal of said second phase-locked-loop circuit that is a multiplier of said output signal to provide a system clock circuit for the acoustic holography system.
Claim 6
Dependent Claim
20 words
The system of claim 4 wherein said third phase-loCked-loop circuit has substantially the same configuration as the first phase-locked-loop circuit.
Claim 7
Dependent Claim
48 words
The system of claim 3 wherein said second low pass filter has selected components which provide a memory signal such that loss of incoming signals to the input circuit for brief periods of time does not cause the voltage controlled oscillator to deviate from its then operating signal.
References Cited (Backward Citations)
US3599142A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |