US3796989A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direction sensitive doppler processor
Assignee: Westinghouse Electric Corp
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Filing: 1972-06-01
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Granted: 1974-03-12
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Expires: 1992-06-01
Abstract
Abstract The invention relates to an improvement in direction sensitive ultrasonic Doppler detecting devices wherein an ultrasonic transducer transmits a given frequency signal toward an object which in turn reflects the given signal and Doppler shifted signals based on the movement of the object. The reflected signals including the Doppler shifted signals are processed and evaluated to determine the characteristics of the object movement both as to direction and degree. The insertion of a differentiating circuit in the processing of the reflected signals minimizes false interpretation of the reflected signals caused by non-harmonic oscillatory movement of the object. Furthermore through the addition of a signal processing circuit utilizing a non-linear multiplier circuit for multiplying the instantaneous values of the components of the reflected signals in contrast to the linear multiplication of these signals, the loss of sensitivity of the Dopper detection device as a function of distance is represented as 1/(distance to object) instead of 1/(distance to object)2 as in the case in the conventional coherent Doppler detection devices.
Inventors
- 👤 P Johnston
- 👤 J Reeves
- 👤 R Ravas
- 👤 T Heinrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:42
CPC Classifications
G; G01; G01S; G01S15/00; G01S15/02; G01S15/50; G01S15/58; G01S15/586; G01S13/00; G01S13/02; G01S13/50; G01S13/58; G01S13/62; G08; G08B; G08B13/00; G08B13/16; G08B13/1609; G08B13/1618; G08B13/1627
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
230 words
In a Doppler-type system for detecting movement of an object, the combination comprising, transmitting means for transmitting a signal at a certain frequency, receiving means for receiving The reflected portion of said signal from the object, first mixing means for deriving a Doppler signal which is the difference in frequency between the transmitted and received signal, first phase shifting means for phase shifting the transmitted signal a predetermined amount, second mixing means for deriving a Doppler signal which is the difference in frequency between the phase shifted transmitted signal and the received signal, differentiating means operatively connected to said second mixing means for differentiating the output signal from said second mixing means to provide an output signal which is phase shifted a second predetermined amount and exhibits an amplitude which is a function of the velocity of the moving object, correlating means for evaluating the signals produced by said first mixing means and said differentiating means to produce an object detection signal indicative of the movement of the object, and measuring means operatively connected to said correlating means, said measuring means including an integrating means, the operation of said differentiating means resulting in an output signal from said integrating means indicative of zero net object movement in response to object movement from a reference position and returning to the reference position regardless of velocity to and from the reference position.
Claim 2
Dependent Claim
230 words
In a Doppler-type system for detecting movement of an object, the combination comprising, transmitting means for transmitting a signal at a certain frequency, receiving means for receiving The reflected portion of said signal from the object, first mixing means for deriving a Doppler signal which is the difference in frequency between the transmitted and received signal, first phase shifting means for phase shifting the transmitted signal a predetermined amount, second mixing means for deriving a Doppler signal which is the difference in frequency between the phase shifted transmitted signal and the received signal, differentiating means operatively connected to said second mixing means for differentiating the output signal from said second mixing means to provide an output signal which is phase shifted a second predetermined amount and exhibits an amplitude which is a function of the velocity of the moving object, correlating means for evaluating the signals produced by said first mixing means and said differentiating means to produce an object detection signal indicative of the movement of the object, and measuring means operatively connected to said correlating means, said measuring means including an integrating means, the operation of said differentiating means resulting in an output signal from said integrating means indicative of zero net object movement in response to object movement from a reference position and returning to the reference position regardless of velocity to and from the reference position.
Claim 3
Dependent Claim
27 words
In a Doppler-type system as claimed in claim 1 wherein said output signal from said differentiating means is in-phase with the output from said first mixing means.
Claim 4
Dependent Claim
28 words
In a Doppler-type system as claimed in claim 1 wherein said output signal from said differentiating means is 180* out-of-phase with the output from said first mixing means.
Claim 5
Dependent Claim
48 words
In a Doppler-type system as claimed in claim 1 wherein said correlating means produces an output signal of a first polarity in response to movement of an object in one direction and an output of opposite polarity in response to movement of the object in an opposite direction.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-11 | 1977-09-10 | 1978-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-11 | 1981-09-10 | 1982-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-11 | 1985-09-10 | 1986-03-12 | $7700.00 | Window Closed / Lapsed |