US6351215B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Monitoring antenna system
Assignee: RF Code Inc
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Filing: 1999-01-20
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Granted: 2002-02-26
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Expires: 2019-01-20
Abstract
Abstract A monitoring system incorporates antennas that transmit signals at predetermined frequencies; the transmitted signals are received by tags located in the active monitoring area of the antenna which then transmit signals back to the antenna. The antennas are tuned to each desired frequency prior to driving the antennas to transmit at the desired frequency. The system transmits a range of frequencies in a sequence that uses overlapping frequency steps. The monitoring system is also constructed having a variable configuration resulting in the ability to be reconfigured under program control to conform to varying system requirements. The integrated monitoring system employs programmable formats for reconfiguration such that upon program input from a host computer the system can assume predetermined configurations to conform to the particular tasks for the specific application. The monitoring system incorporates an antenna system that employs digitally controlled, differentially driven, scanning transceivers, and walk through magnetic induction antennas positionable in various configurations to maximize detection of tags being transported through the antenna system.
Inventors
- 👤 James L. Rodgers
- 👤 Billy C. Fowler
- 👤 Howard K. Jaecks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:02
CPC Classifications
H; H01; H01Q; H01Q23/00; G; G01; G01S; G01S13/00; G01S13/74; G01S13/75; G01S13/751; G01S13/753; G01S13/756; G01S13/758; G06; G06K; G06K19/00; G06K19/06; G06K19/067; G06K19/07; G06K19/0701; G06K19/0723; G06K19/0724; G06K19/077; G06K19/07749; G06K19/07773; G06K19/07777; G06K19/07779; G06K19/07783; G06K7/00; G06K7/0008; G06K7/10; G06K7/10009; G06K7/10316; G06K7/10336; G06K7/10346; H01Q1/00; H01Q1/12; H01Q1/22; H01Q1/2208; H01Q1/36; H01Q1/38; H01Q21/00; H01Q21/28; H01Q7/00
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
97 words
In a monitoring system for detecting the presence of a tag the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; an antenna tap connected to said signal source for receiving said digital signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a planar antenna loop connected to said antenna tap for transmitting signals at the signal frequency of said analog signal; wherein said antenna is responsive to signals from said tap for generating a magnetic field surrounding said loop at said analog signal frequency.
Claim 2
Dependent Claim
97 words
In a monitoring system for detecting the presence of a tag the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; an antenna tap connected to said signal source for receiving said digital signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a planar antenna loop connected to said antenna tap for transmitting signals at the signal frequency of said analog signal; wherein said antenna is responsive to signals from said tap for generating a magnetic field surrounding said loop at said analog signal frequency.
Claim 3
Dependent Claim
82 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; an antenna tap connected to said signal source for receiving said digital signals and generating an analog signal having a signal frequency of one of said selected frequencies, said tap including differential antenna drivers; and a differentially drive planar antenna loop connected to said antenna drivers for transmitting signals at the signal frequency of said analog signal.
Claim 4
Dependent Claim
82 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; an antenna tap connected to said signal source for receiving said digital signals and generating an analog signal having a signal frequency of one of said selected frequencies, said tap including differential antenna drivers; and a differentially drive planar antenna loop connected to said antenna drivers for transmitting signals at the signal frequency of said analog signal.
Claim 5
Dependent Claim
32 words
The combination set forth in claim 2 wherein said antenna is responsive to the analog signals from said drivers for generating a magnetic field surrounding said loop at said analog signal frequency.
Claim 6
Dependent Claim
120 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; an antenna tap connected to said signal source for receiving said digital signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a portal planar loop antenna connected to said antenna tap for transmitting signals at the signal frequency of said analog signal; wherein said antenna is responsive to the signals from said tap for generating a magnetic field surrounding said loop at said analog signal frequency; and said portal antenna has a magnetic field coupling to the tag in said magnetic field being transported through said loop.
Claim 7
Dependent Claim
120 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; an antenna tap connected to said signal source for receiving said digital signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a portal planar loop antenna connected to said antenna tap for transmitting signals at the signal frequency of said analog signal; wherein said antenna is responsive to the signals from said tap for generating a magnetic field surrounding said loop at said analog signal frequency; and said portal antenna has a magnetic field coupling to the tag in said magnetic field being transported through said loop.
Claim 8
Dependent Claim
31 words
The improvement set forth in claim 4 wherein said portal antenna is positioned and sized to permit tag carrying items to be transported perpendicularly through the plane of said antenna loop.
Claim 9
Dependent Claim
119 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; an antenna tap connected to said signal source for receiving said digital signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a transversal planar loop antenna connected to said antenna tap for transmitting signals at the signal frequency of said analog signal; wherein said antenna is responsive to signals from said tap for generating a magnetic field surrounding said loop at said analog signal frequency; and said transversal antenna has a magnetic field coupling to the tag in said magnetic field being transported adjacent said loop.
Claim 10
Dependent Claim
119 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; an antenna tap connected to said signal source for receiving said digital signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a transversal planar loop antenna connected to said antenna tap for transmitting signals at the signal frequency of said analog signal; wherein said antenna is responsive to signals from said tap for generating a magnetic field surrounding said loop at said analog signal frequency; and said transversal antenna has a magnetic field coupling to the tag in said magnetic field being transported adjacent said loop.
Claim 11
Dependent Claim
38 words
The improvement set forth in claim 6 wherein said transversal antenna is positioned and sized to permit tag carrying items to be transported through the magnetic field of said antenna parallel to the plane of said antenna loop.
Claim 12
Dependent Claim
128 words
In a monitoring system for detecting the presence of a tag the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; a plurality of antenna taps connected to said signal source for receiving said digital signals and generating respective first and second analog signals each having a frequency corresponding to one of said selected frequencies; a first planar antenna loop connected to one of said antenna taps for transmitting signals at the signal frequency of the first analog signal; and a second planar antenna loop connected to another of said antenna taps for transmitting signals at the signal frequency of the second analog signal; wherein said first and second planar antenna loops are positioned in planes at an angle with respect to each other.
Claim 13
Dependent Claim
128 words
In a monitoring system for detecting the presence of a tag the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; a plurality of antenna taps connected to said signal source for receiving said digital signals and generating respective first and second analog signals each having a frequency corresponding to one of said selected frequencies; a first planar antenna loop connected to one of said antenna taps for transmitting signals at the signal frequency of the first analog signal; and a second planar antenna loop connected to another of said antenna taps for transmitting signals at the signal frequency of the second analog signal; wherein said first and second planar antenna loops are positioned in planes at an angle with respect to each other.
Claim 14
Dependent Claim
13 words
The improvement set forth in claim 8 wherein said planes intersect each other.
Claim 15
Dependent Claim
19 words
The improvement set forth in claim 8 wherein said antennas are portal antennas and said angle is about 45°.
Claim 16
Dependent Claim
58 words
The improvement set forth in claim 10 wherein the first planar antenna loop and the second planar antenna loop are formed around an axis; the first plane is perpendicular to the axis; and a line of intersection, between the second plane and a vertical plane that includes the axis, forms an angle of about 45° with the axis.
Claim 17
Dependent Claim
155 words
In a monitoring system for detecting the presence of a tag the improvement comprising; a digital signal source for generating digital signals representing selected frequencies; a plurality of antenna taps connected to said signal source for receiving said digital signals and generating respective first and second analog signals each having a frequency corresponding to one of said selected frequencies; a first portal planar antenna loop connected to one of said antenna taps for transmitting signals at the signal frequency of the first analog signal; and a second portal planar antenna loop connected to another of said antenna taps for transmitting signals at the signal frequency of the second analog signal; wherein said first and second portal planar antenna loops are positioned in parallel planes spaced along a path of the tag to be detected; and each of said antenna loops is driven differentially with respect to each other to cancel noise existing along said path.
Claim 18
Dependent Claim
155 words
In a monitoring system for detecting the presence of a tag the improvement comprising; a digital signal source for generating digital signals representing selected frequencies; a plurality of antenna taps connected to said signal source for receiving said digital signals and generating respective first and second analog signals each having a frequency corresponding to one of said selected frequencies; a first portal planar antenna loop connected to one of said antenna taps for transmitting signals at the signal frequency of the first analog signal; and a second portal planar antenna loop connected to another of said antenna taps for transmitting signals at the signal frequency of the second analog signal; wherein said first and second portal planar antenna loops are positioned in parallel planes spaced along a path of the tag to be detected; and each of said antenna loops is driven differentially with respect to each other to cancel noise existing along said path.
Claim 19
Dependent Claim
135 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; a first antenna tap and a second antenna tap each connected to said signal source for receiving said digital signals and generating analog signals each having a frequency correspondence to one of said selected frequencies; and a first planar antenna loop connected to said first antenna tap for transmitting signals at the signal frequency of the first analog signal; a second planar antenna loop connected to said second antenna tap for transmitting signals at the signal frequency of the second analog signal; wherein said first and second antenna taps drive said first and second planar antenna loops respectively with respective signals that are phase shifted with respect to each other.
Claim 20
Dependent Claim
135 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; a first antenna tap and a second antenna tap each connected to said signal source for receiving said digital signals and generating analog signals each having a frequency correspondence to one of said selected frequencies; and a first planar antenna loop connected to said first antenna tap for transmitting signals at the signal frequency of the first analog signal; a second planar antenna loop connected to said second antenna tap for transmitting signals at the signal frequency of the second analog signal; wherein said first and second antenna taps drive said first and second planar antenna loops respectively with respective signals that are phase shifted with respect to each other.
Claim 21
Dependent Claim
14 words
The combination set forth in claim 13 wherein said phase shift is about 90°.
Claim 22
Dependent Claim
119 words
In a monitoring system for detecting the presence of a tag the improvement comprising: a digital signal source for generating digital signals representing selected frequencies and for generating transmit mode signals and receive mode signals; an antenna tap connected to said signal source for receiving said digital signals and said mode signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a planar transceiver antenna loop connected to said antenna tap for transmitting signals at the signal frequencies of said analog signal and for receiving signals transmitted by the tag; wherein said antenna tap is connected to said planar transceiver antenna loop for receiving and amplifying tag signals detected by said antenna.
Claim 23
Dependent Claim
119 words
In a monitoring system for detecting the presence of a tag the improvement comprising: a digital signal source for generating digital signals representing selected frequencies and for generating transmit mode signals and receive mode signals; an antenna tap connected to said signal source for receiving said digital signals and said mode signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a planar transceiver antenna loop connected to said antenna tap for transmitting signals at the signal frequencies of said analog signal and for receiving signals transmitted by the tag; wherein said antenna tap is connected to said planar transceiver antenna loop for receiving and amplifying tag signals detected by said antenna.
Claim 24
Dependent Claim
30 words
The combination set forth in claim 15 wherein said antenna is responsive to signals from said tap for generating a magnetic field surrounding said loop at said analog signal frequency.
Claim 25
Dependent Claim
18 words
The combination set forth in claim 15 wherein said antenna tap differentially drives said planar transceiver loop antenna.
Claim 26
Dependent Claim
152 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies and for generating transmit mode signals and receive mode signals; an antenna tap connected to said signal source for receiving said digital signals and mode signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a planar portal transceiver loop antenna connected to said antenna tap for transmitting signals at the signal frequency of said analog signal and for receiving signals transmitted by the tag; wherein said portal planar transceiver loop antenna is responsive to signals from said tap for generating a magnetic field surrounding said loop at said analog signal frequency and is responsive to signals received from a tag; and said antenna tap is connected to said antenna for receiving and amplifying tag signals detected by said antenna.
Claim 27
Dependent Claim
152 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies and for generating transmit mode signals and receive mode signals; an antenna tap connected to said signal source for receiving said digital signals and mode signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a planar portal transceiver loop antenna connected to said antenna tap for transmitting signals at the signal frequency of said analog signal and for receiving signals transmitted by the tag; wherein said portal planar transceiver loop antenna is responsive to signals from said tap for generating a magnetic field surrounding said loop at said analog signal frequency and is responsive to signals received from a tag; and said antenna tap is connected to said antenna for receiving and amplifying tag signals detected by said antenna.
Claim 28
Dependent Claim
138 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies and for generating transmit mode signals and receive mode signals; an antenna tap connected to said signal source for receiving said digital signals and said mode signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a planar transceiver antenna loop connected to said antenna tap for transmitting signals at the signal frequency of said analog signal and for receiving signals transmitted by the tag; wherein said antenna tap responsive to said mode signals for selecting the reactance of a resonant circuit including said antenna; and said planar transceiver antenna loop has a higher Q during said transmit mode signal than during said receive mode signal.
Claim 29
Dependent Claim
138 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies and for generating transmit mode signals and receive mode signals; an antenna tap connected to said signal source for receiving said digital signals and said mode signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a planar transceiver antenna loop connected to said antenna tap for transmitting signals at the signal frequency of said analog signal and for receiving signals transmitted by the tag; wherein said antenna tap responsive to said mode signals for selecting the reactance of a resonant circuit including said antenna; and said planar transceiver antenna loop has a higher Q during said transmit mode signal than during said receive mode signal.
Claim 30
Dependent Claim
160 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies and for generating transmit mode signals, receive mode, signals, and squelch mode signals; an antenna tap connected to said signal source for receiving said digital signals and mode signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a planar transceiver loop antenna connected to said antenna tap for transmitting signals at the signal frequency of said analog signal and for receiving signals transmitted by the tag; wherein said antenna tap is responsive to said mode signals for selecting the reactance of a resonant circuit including said antenna and for squelching all transmissions in response to said squelch mode signal; and said planar transceiver antenna loop has a higher Q during said transmit mode signal than during said receive mode signal and being squelched during said squelch signal.
Claim 31
Dependent Claim
160 words
In a monitoring system for detecting the presence of a tag, the improvement comprising: a digital signal source for generating digital signals representing selected frequencies and for generating transmit mode signals, receive mode, signals, and squelch mode signals; an antenna tap connected to said signal source for receiving said digital signals and mode signals and generating an analog signal having a signal frequency of one of said selected frequencies; and a planar transceiver loop antenna connected to said antenna tap for transmitting signals at the signal frequency of said analog signal and for receiving signals transmitted by the tag; wherein said antenna tap is responsive to said mode signals for selecting the reactance of a resonant circuit including said antenna and for squelching all transmissions in response to said squelch mode signal; and said planar transceiver antenna loop has a higher Q during said transmit mode signal than during said receive mode signal and being squelched during said squelch signal.
Claim 32
Dependent Claim
108 words
In a monitoring system for detecting the presence of a tag the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; an antenna tap connected to said signal source for receiving said digital signals and generating an analog signal having a signal frequency of one of said selected frequencies; a planar transceiver antenna loop connected to said antenna tap for transmitting signals at the signal frequency of said analog signal and for receiving signals transmitted by the tag; and a resonant circuit including said antenna; wherein said resonant circuit has a higher Q when said antenna is transmitting than when said antenna is receiving.
Claim 33
Dependent Claim
108 words
In a monitoring system for detecting the presence of a tag the improvement comprising: a digital signal source for generating digital signals representing selected frequencies; an antenna tap connected to said signal source for receiving said digital signals and generating an analog signal having a signal frequency of one of said selected frequencies; a planar transceiver antenna loop connected to said antenna tap for transmitting signals at the signal frequency of said analog signal and for receiving signals transmitted by the tag; and a resonant circuit including said antenna; wherein said resonant circuit has a higher Q when said antenna is transmitting than when said antenna is receiving.
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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) | 2005-02-25 | 2005-08-27 | 2006-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-02-25 | 2009-08-27 | 2010-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-02-25 | 2013-08-27 | 2014-02-26 | $7700.00 | Window Closed / Lapsed |