US6825456B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signal processing for object detection system
Assignee: Peacock Law Pc
•
Filing: 2002-01-29
•
Granted: 2004-11-30
•
Expires: 2022-01-29
Abstract
Abstract Methods and apparatus for detecting objects. In one embodiment, a person entering a secured or “Safe Zone™” is illuminated with low-power polarized radio waves. Differently polarized waves which are reflected back from the person are collected and measured. In a preferred embodiment, concealed weapons are detected by calculating the difference of a pair of differences (Delta A and B) of different polarized reflected energy (upper and lower curves in the two graphs) in the time domain, and by using signal processing methods and apparatus to improve the reliability of the detection process.
Inventors
- 👤 George G. Chadwick
- 👤 Jerry Hausner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 16:02
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/88; G01S13/887; G01S7/00; G01S7/02; G01S7/024; G01S7/025; G01S7/41; G01S7/411; G01S7/412; G01V; G01V3/00; G01V3/12; G01S7/28; G01S7/285; G01S7/288; G01S7/2883
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
107 words
A method of detecting an object comprising the steps of: illuminating a target with polarized radiation; collecting first radiation reflected from said target which has a polarization which is the same as the radiation used to illuminate said target; collecting second radiation reflected from said target which is oppositely polarized to that of said radiation which is used to illuminate said target; and comparing a difference between amplitudes of said first and second radiation with a predetermined value representative of an expected difference were the object not present; and wherein a single receiver channel is employed by the two collecting steps, which receiver channel is time multiplexed.
Claim 2
Independent Claim
107 words
A method of detecting an object comprising the steps of: illuminating a target with polarized radiation; collecting first radiation reflected from said target which has a polarization which is the same as the radiation used to illuminate said target; collecting second radiation reflected from said target which is oppositely polarized to that of said radiation which is used to illuminate said target; and comparing a difference between amplitudes of said first and second radiation with a predetermined value representative of an expected difference were the object not present; and wherein a single receiver channel is employed by the two collecting steps, which receiver channel is time multiplexed.
Claim 3
Dependent Claim
19 words
A method as recited in claim 1 , wherein the receiver channel is time multiplexed with a microwave switch.
Claim 4
Dependent Claim
16 words
A method as recited in claim 1 , wherein the illuminating step comprises transmitting pulse doublets.
Claim 5
Dependent Claim
15 words
A method as recited in claim 1 , in which said target is a person.
Claim 6
Dependent Claim
16 words
A method as recited in claim 4 , in which said object is a concealed weapon.
Claim 7
Dependent Claim
16 words
A method as recited in claim 5 , in which said concealed weapon is a firearm.
Claim 8
Dependent Claim
37 words
A method as recited in claim 1 , additionally comprising the step of using a Fast Fourier Transform to substantially discount the moving components of said target to improve the detection of unchanging components of said target.
Claim 9
Dependent Claim
23 words
A method as recited in claim 7 , additionally comprising the step of generating a reference signal from sampling transmit and local oscillators.
Claim 10
Dependent Claim
17 words
A method as recited in claim 1 , in which said target is illuminated with radio waves.
Claim 11
Independent Claim
122 words
A method of detecting an object comprising the steps of: illuminating a target with polarized radiation; collecting first radiation reflected from said target which has a polarization which is the same as the radiation used to illuminate said target; collecting second radiation reflected from said target which is oppositely polarized to that of said radiation which is used to illuminate said target; generating a reference signal from sampling transmit and local oscillators; comparing a difference between amplitudes of said first and second radiation with a predetermined value representative of an expected difference were the object not present; and using a Fast Fourier Transform to substantially discount the moving components of said target to improve the detection of unchanging components of said target.
Claim 12
Independent Claim
122 words
A method of detecting an object comprising the steps of: illuminating a target with polarized radiation; collecting first radiation reflected from said target which has a polarization which is the same as the radiation used to illuminate said target; collecting second radiation reflected from said target which is oppositely polarized to that of said radiation which is used to illuminate said target; generating a reference signal from sampling transmit and local oscillators; comparing a difference between amplitudes of said first and second radiation with a predetermined value representative of an expected difference were the object not present; and using a Fast Fourier Transform to substantially discount the moving components of said target to improve the detection of unchanging components of said target.
Claim 13
Dependent Claim
15 words
A method as recited in claim 10 , in which said target is a person.
Claim 14
Dependent Claim
16 words
A method as recited in claim 11 , in which said object is a concealed weapon.
Claim 15
Dependent Claim
16 words
A method as recited in claim 12 , in which said concealed weapon is a firearm.
Claim 16
Dependent Claim
26 words
A method as recited in claim 10 , wherein a single receiver channel is employed by the two collecting steps, which receiver channel is time multiplexed.
Claim 17
Dependent Claim
19 words
A method as recited in claim 14 , wherein the receiver channel is time multiplexed with a microwave switch.
Claim 18
Dependent Claim
16 words
A method as recited in claim 10 , wherein the illuminating step comprises transmitting pulse doublets.
Claim 19
Dependent Claim
17 words
A method as recited in claim 10 , in which said target is illuminated with radio waves.
References Cited (Backward Citations)
US3500395A
Cited
US3599211A
Cited
US3669038A
Cited
US3911435A
Cited
US3713156A
Cited
US3707672A
Cited
US3924546A
Cited
US4122783A
Cited
US4341165A
Cited
US4586441A
Cited
US4481887A
Cited
US4461221A
Cited
US4706031A
Cited
US4656954A
Cited
US4675677A
Cited
US4905008A
Cited
US5081456A
Cited
US5227800A
Cited
US4951058A
Cited
US5039981A
Cited
US5408414A
Cited
US5222155A
Cited
US5381153A
Cited
US5557283A
Cited
US5455590A
Cited
US5552776A
Cited
US5195448A
Cited
US5774357A
Cited
US5334981A
Cited
US5576972A
Cited
US5517429A
Cited
US5311166A
Cited
US5692446A
Cited
US5457394A
Cited
US5519400A
Cited
US5512834A
Cited
US5365237A
Cited
US5337053A
Cited
US5446461A
Cited
US5694867A
Cited
US5706402A
Cited
WO1996019737A1
Cited
US5598152A
Cited
US5552705A
Cited
WO1997001771A1
Cited
US5644314A
Cited
JPH09304517A
Cited
US5673050A
Cited
US5694498A
Cited
US6359582B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2007-11-30 | 2008-05-31 | 2008-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-11-30 | 2012-05-31 | 2012-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-11-30 | 2016-05-31 | 2016-11-30 | $7700.00 | Window Closed / Lapsed |