Patent US5942899A successfully refreshed from Google Patents.
US5942899A
Expired / Lapsed
US
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Hyperspectral radiometric mine detector based upon sensing microwave brightness temperature and interference contrast signatures
Assignee: Northrop Grumman Systems Corp
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Filing: 1997-07-28
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Granted: 1999-08-24
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Expires: 2017-07-28
Abstract
Abstract A passive mine detection apparatus useful for searching out buried mines, exploits natural soil emissions at microwave frequencies and unique interference-induced spectral reflection signatures from planar surfaces of buried mines interacting with the soil emissions. The apparatus comprises a focussed beam antenna, low noise amplifiers for respective polarizations, baseband converter, spectrum analyzer, A to D converter, signature recognition processor, display and/or alarm. Hand-held and vehicle-mounted implementations are disclosed.
Inventors
- 👤 Abraham Shrekenhamer
- 👤 Mostafa Karam
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 03:33
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/12
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
92 words
An apparatus for detecting buried mines; the apparatus comprising: an antenna for receiving selected frequency signals; at least one low-noise amplifier for amplifying said signals; a programmable filter for sampling the frequency spectrum of said signals; a video detector for detecting selected frequency within said spectrum; a video integrator and amplifier for generating a selected range of said spectrum; an analog-to-digital converter for digitizing said selected spectrum range; a processor for detecting a pre-selected radiometric signature within said digitized spectrum range; and a display for generating a visual representation of mine detection.
Claim 2
Independent Claim
92 words
An apparatus for detecting buried mines; the apparatus comprising: an antenna for receiving selected frequency signals; at least one low-noise amplifier for amplifying said signals; a programmable filter for sampling the frequency spectrum of said signals; a video detector for detecting selected frequency within said spectrum; a video integrator and amplifier for generating a selected range of said spectrum; an analog-to-digital converter for digitizing said selected spectrum range; a processor for detecting a pre-selected radiometric signature within said digitized spectrum range; and a display for generating a visual representation of mine detection.
Claim 3
Dependent Claim
21 words
The apparatus recited in claim 1 further comprising a programmable frequency source and a mixer for downconverting said signals to baseband.
Claim 4
Dependent Claim
24 words
The apparatus recited in claim 1 wherein said antenna is configured for receiving signals in the frequency range of 1 GHz to 10 GHz.
Claim 5
Dependent Claim
22 words
The apparatus recited in claim 1 wherein said signals comprise natural radiance emissions from soil and interfering reflections from buried mine surfaces.
Claim 6
Dependent Claim
23 words
The apparatus recited in claim 1 further comprising means for separately processing radiometric signatures resulting from horizontal and vertical polarizations of said signals.
Claim 7
Dependent Claim
22 words
The apparatus recited in claim 1 further comprising an audible alarm activated by a signature corresponding to detection of a buried mine.
Claim 8
Dependent Claim
18 words
The apparatus recited in claim 1 wherein said antenna comprises a movable lens feed for changing focal length.
Claim 9
Dependent Claim
18 words
The apparatus recited in claim 1 wherein said antenna comprises a movable reflector feed for changing focal length.
Claim 10
Dependent Claim
14 words
The apparatus recited in claim 1 wherein said apparatus is configured for hand-held implementation.
Claim 11
Dependent Claim
14 words
The apparatus recited in claim 1 wherein said apparatus is configured for vehicle-mounted implementation.
Claim 12
Independent Claim
92 words
An apparatus for use in searching for and detecting buried mines; the apparatus comprising: an antenna for receiving naturally occurring radiometric emissions from soil; a baseband converter for converting said emissions to a baseband frequency; a spectrum analyzer for generating the frequency spectrum of said emissions; a spectral signature analyzer for recognizing the frequency spectrum signature of a buried mine; and a mine signature recognition indicator for alerting a user of a detected mine; wherein said antenna is configured for receiving signals in the frequency range of 1 GHz to 10 GHz.
Claim 13
Independent Claim
92 words
An apparatus for use in searching for and detecting buried mines; the apparatus comprising: an antenna for receiving naturally occurring radiometric emissions from soil; a baseband converter for converting said emissions to a baseband frequency; a spectrum analyzer for generating the frequency spectrum of said emissions; a spectral signature analyzer for recognizing the frequency spectrum signature of a buried mine; and a mine signature recognition indicator for alerting a user of a detected mine; wherein said antenna is configured for receiving signals in the frequency range of 1 GHz to 10 GHz.
Claim 14
Dependent Claim
22 words
The apparatus recited in claim 11 wherein said emissions comprise natural radiance emissions from soil and interfering reflections from buried mine surfaces.
Claim 15
Independent Claim
91 words
An apparatus for use in searching for and detecting buried mines; the apparatus comprising: an antenna for receiving naturally occurring radiometric emissions from soil; a baseband converter for converting said emissions to a baseband frequency; a spectrum analyzer for generating the frequency spectrum of said emissions; a spectral signature analyzer for recognizing the frequency spectrum signature of a buried mine; and a mine signature recognition indicator for alerting a user of a detected mine; further comprising means for separately processing radiometric signatures resulting from horizontal and vertical polarizations of said signals.
Claim 16
Independent Claim
91 words
An apparatus for use in searching for and detecting buried mines; the apparatus comprising: an antenna for receiving naturally occurring radiometric emissions from soil; a baseband converter for converting said emissions to a baseband frequency; a spectrum analyzer for generating the frequency spectrum of said emissions; a spectral signature analyzer for recognizing the frequency spectrum signature of a buried mine; and a mine signature recognition indicator for alerting a user of a detected mine; further comprising means for separately processing radiometric signatures resulting from horizontal and vertical polarizations of said signals.
Claim 17
Dependent Claim
22 words
The apparatus recited in claim 1 further comprising an audible alarm activated by a signature corresponding to detection of a buried mine.
Claim 18
Independent Claim
86 words
An apparatus for use in searching for and detecting buried mines; the apparatus comprising: an antenna for receiving naturally occurring radiometric emissions from soil; a baseband converter for converting said emissions to a baseband frequency; a spectrum analyzer for generating the frequency spectrum of said emissions; a spectral signature analyzer for recognizing the frequency spectrum signature of a buried mine; and a mine signature recognition indicator for alerting a user of a detected mine; wherein said antenna comprises a movable lens feed for changing focal length.
Claim 19
Independent Claim
86 words
An apparatus for use in searching for and detecting buried mines; the apparatus comprising: an antenna for receiving naturally occurring radiometric emissions from soil; a baseband converter for converting said emissions to a baseband frequency; a spectrum analyzer for generating the frequency spectrum of said emissions; a spectral signature analyzer for recognizing the frequency spectrum signature of a buried mine; and a mine signature recognition indicator for alerting a user of a detected mine; wherein said antenna comprises a movable lens feed for changing focal length.
Claim 20
Independent Claim
86 words
An apparatus for use in searching for and detecting buried mines; the apparatus comprising: an antenna for receiving naturally occurring radiometric emissions from soil; a baseband converter for converting said emissions to a baseband frequency; a spectrum analyzer for generating the frequency spectrum of said emissions; a spectral signature analyzer for recognizing the frequency spectrum signature of a buried mine; and a mine signature recognition indicator for alerting a user of a detected mine; wherein said antenna comprises a movable reflector feed for changing focal length.
Claim 21
Independent Claim
86 words
An apparatus for use in searching for and detecting buried mines; the apparatus comprising: an antenna for receiving naturally occurring radiometric emissions from soil; a baseband converter for converting said emissions to a baseband frequency; a spectrum analyzer for generating the frequency spectrum of said emissions; a spectral signature analyzer for recognizing the frequency spectrum signature of a buried mine; and a mine signature recognition indicator for alerting a user of a detected mine; wherein said antenna comprises a movable reflector feed for changing focal length.
Claim 22
Dependent Claim
14 words
The apparatus recited in claim 13 wherein said apparatus is configured for hand-held implementation.
Claim 23
Dependent Claim
14 words
The apparatus recited in claim 13 wherein said apparatus is configured for vehicle-mounted implementation.
Claim 24
Dependent Claim
21 words
The apparatus recited in claim 15 wherein said focal length change is implemented by altering axial feed position of said antenna.
Claim 25
Dependent Claim
21 words
The apparatus recited in claim 16 wherein said focal length change is implemented by altering axial feed position of said antenna.
References Cited (Backward Citations)
US4825165A
Cited
US4766385A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-08-23 | 2003-02-22 | 2003-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-08-23 | 2007-02-22 | 2007-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-08-23 | 2011-02-22 | 2011-08-24 | $7700.00 | Window Closed / Lapsed |