US6765527B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
System and method of radar detection of non-linear interfaces
Assignee: Johns Hopkins University
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Filing: 2002-01-31
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Granted: 2004-07-20
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Expires: 2022-01-31
Abstract
Abstract A harmonic radar nonlinear junction detector system for detecting concealed weapons, electronics, and other man-made objects utilizing state-of-the art wireless technology, circuit fabrication, signal synthesis, and computer processing techniques to detect and characterize man-made objects possessing nonlinear junctions. The system transmits a pair of low power waveforms and a receiver within the system is coherently tuned to harmonics of the transmitted frequencies of the waveforms to detect man-made metal objects and electronics that contain non-linear junctions. The receiver is also capable of receiving inter-modulation products reflected from the man-made objects that are a result of using two incident signals. The system uses two signal sources generating user-definable waveforms of variable frequencies in order to provide enhanced discrimination and target identification abilities via the processing of returned inter-modulation products.
Inventors
- 👤 Daniel G. Jablonski
- 👤 Harvey W. Ko
- 👤 Douglas A. Oursler
- 👤 Dexter G. Smith
- 👤 David M. White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:33
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/02; G01S7/41; G01S7/411; G01N; G01N22/00; G01S13/00; G01S13/02; G01S13/06; G01S13/08; G01S13/32; G01S13/34; G01S13/347; G01S17/00; G01S17/87
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
331 words
A system for detecting and characterizing man-made objects that possess nonlinear junctions in which incident signals are transmitted into free space, and upon contact with said man-made objects that possess nonlinear junctions, said man-made objects that possess nonlinear junctions will reflect new signals that can be received and characterized, said system comprising: a first signal generator that generates a first incident signal, f 1 ; a second signal generator that generates a second incident signal, f 2 , wherein said first incident signal, f 1 , has a high frequency and said second incident signal, f 2 , has a low frequency; transmit circuitry that transmits said first signal, f 1 , and said second signal, f 2 ; receive circuitry that is tuned to receive signals that are exact harmonic multiples of said incident signals, f 1 and f 2 , and is also tuned to receive inter-modulation products that are reflected from said man-made objects that possess nonlinear junctions as a result of said man-made objects being illuminated by said incident signals f 1 and f 2 ; an antenna assembly coupled with said transmit and receive circuitry and including a high frequency directional array antenna that assists in the transmission of said first incident signal, f 1 , and a low frequency omni-directional array antenna that assists in the transmission of said second incident signal, f 2 , wherein said antenna assembly also assists in the reception of reflected signals from said man-made objects that possess nonlinear junctions; a signal processor that processes said received reflected signals from said man-made objects that possess nonlinear junctions such that the man-made objects can be characterized according to their composition; a master clock that synchronizes said first signal generator, said second signal generator, said receive circuitry, said transmit circuitry, and said signal processor; and a data bus that couples said master clock, said first signal generator, said second signal generator, said receive circuitry, said transmit circuitry, and said signal processor together.
Claim 2
Independent Claim
331 words
A system for detecting and characterizing man-made objects that possess nonlinear junctions in which incident signals are transmitted into free space, and upon contact with said man-made objects that possess nonlinear junctions, said man-made objects that possess nonlinear junctions will reflect new signals that can be received and characterized, said system comprising: a first signal generator that generates a first incident signal, f 1 ; a second signal generator that generates a second incident signal, f 2 , wherein said first incident signal, f 1 , has a high frequency and said second incident signal, f 2 , has a low frequency; transmit circuitry that transmits said first signal, f 1 , and said second signal, f 2 ; receive circuitry that is tuned to receive signals that are exact harmonic multiples of said incident signals, f 1 and f 2 , and is also tuned to receive inter-modulation products that are reflected from said man-made objects that possess nonlinear junctions as a result of said man-made objects being illuminated by said incident signals f 1 and f 2 ; an antenna assembly coupled with said transmit and receive circuitry and including a high frequency directional array antenna that assists in the transmission of said first incident signal, f 1 , and a low frequency omni-directional array antenna that assists in the transmission of said second incident signal, f 2 , wherein said antenna assembly also assists in the reception of reflected signals from said man-made objects that possess nonlinear junctions; a signal processor that processes said received reflected signals from said man-made objects that possess nonlinear junctions such that the man-made objects can be characterized according to their composition; a master clock that synchronizes said first signal generator, said second signal generator, said receive circuitry, said transmit circuitry, and said signal processor; and a data bus that couples said master clock, said first signal generator, said second signal generator, said receive circuitry, said transmit circuitry, and said signal processor together.
Claim 3
Dependent Claim
25 words
The system of claim 1 wherein said first signal generator generates a first incident signal, f 1 , having a frequency of approximately 1 GHz.
Claim 4
Dependent Claim
44 words
The system of claim 1 wherein said first signal generator generates a first incident signal, f 1 , and said second signal generator generates a second incident signal, f 2 , having a frequency close to but different than that off f 1 .
Claim 5
Dependent Claim
27 words
The system of claim 1 wherein said first signal generator generates a first incident signal, f 1 , having a frequency within the range of 10-24 GHz.
Claim 6
Dependent Claim
42 words
The system of claim 1 wherein said first signal generator generates a first incident signal, f 1 , and said second signal generator generates a second incident signal, f 2 , having a frequency much lower than that of f 1 .
Claim 7
Dependent Claim
44 words
The system of claim 1 wherein a second system, having its master clock synchronized to the master clock of the original system via a common timing mechanism, is used to provide antenna aperture enhancement such that the spatial resolution of the systems is increased.
Claim 8
Dependent Claim
33 words
The system of claim 1 in which a synthetic antenna aperture enhancement is achieved by operating the system at two different locations at a known time interval with respect to a man-made object.
Claim 9
Dependent Claim
22 words
The system of claim 1 further including an operator display for displaying results of the signal processor with respect to man-made objects.
Claim 10
Dependent Claim
26 words
The system of claim 1 further including audio output capabilities for notifying an operator of the results of the signal processor with respect to man-made objects.
Claim 11
Dependent Claim
18 words
The system of claim 1 further including a user interface for controlling the frequency of the transmitted waveforms.
Claim 12
Dependent Claim
15 words
The system of claim 1 in which the system is implemented into a fixed portal.
Claim 13
Dependent Claim
33 words
The system of claim 1 in which the system is implemented as a portable wearable unit that can be discreetly worn by an individual and used while the individual moves about an area.
Claim 14
Dependent Claim
24 words
The system of claim 1 in which the system is implemented as a portable unit that can be used while moving about an area.
Claim 15
Dependent Claim
34 words
The system of claim 1 wherein the signal processor is configured to process said received reflected signals from said man-made objects that possess nonlinear junctions without canceling said received reflected signals from one another.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2007-07-20 | 2008-01-19 | 2008-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-07-20 | 2012-01-19 | 2012-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-07-20 | 2016-01-19 | 2016-07-20 | $7700.00 | Window Closed / Lapsed |