Patent US5828693A successfully refreshed from Google Patents.
US5828693A
Expired / Lapsed
US
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Spread spectrum frequency hopping reader system
Assignee: Intermec IP Corp
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Filing: 1996-03-21
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Granted: 1998-10-27
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Expires: 2016-03-21
Abstract
Abstract An apparatus for sourcing an interrogation signal for use in a object identification system including a frequency hopping source for generation of an interrogation signal which is coupled to a homo dyne radio for transmission by a bi-directional antenna to a tag. Upon receipt, the tag provides a return signal that is backscatter modulated to include tag identification or other data which is processed by the sourcing system. The frequency hopping source includes a voltage controller oscillator which is driven by a pseudo random code generator for selecting one of a plurality of hopping frequencies at which the interrogation signal is to be generated based on the available bandwidth.
Inventors
- 👤 Wesley M. Mays
- 👤 Aaron J. Kam Siu
- 👤 Mike D. Fontanarosa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:59
CPC Classifications
G; G07; G07B; G07B15/00; G07B15/06; G07B15/063; G06; G06K; G06K7/00; G06K7/0008; G08; G08G; G08G1/00; G08G1/01; G08G1/017; H; H04; H04B; H04B1/00; H04B1/69; H04B1/713; H04B1/715; H04B1/7136; H04B2001/71365
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
119 words
A reader for use in an interrogation system, the reader generating a radio frequency signal to be returned by an electronic tag when the tag enters a predefined envelope region associated with the reader, the reader comprising: a radio frequency source outputting a radio frequency signal at one of a plurality of frequencies within a frequency range; means for hopping the radio frequency signal according to a first sequence among the plurality of frequencies in the frequency range; a detector for detecting destructive interference in a return signal from an electronic tag located within an envelope region associated with the reader; and a controller operating to vary the hopping upon the detection of destructive interference in the return signal.
Claim 2
Dependent Claim
119 words
A reader for use in an interrogation system, the reader generating a radio frequency signal to be returned by an electronic tag when the tag enters a predefined envelope region associated with the reader, the reader comprising: a radio frequency source outputting a radio frequency signal at one of a plurality of frequencies within a frequency range; means for hopping the radio frequency signal according to a first sequence among the plurality of frequencies in the frequency range; a detector for detecting destructive interference in a return signal from an electronic tag located within an envelope region associated with the reader; and a controller operating to vary the hopping upon the detection of destructive interference in the return signal.
Claim 3
Dependent Claim
15 words
The apparatus of claim 1 where the radio frequency source is a voltage controlled oscillator.
Claim 4
Dependent Claim
25 words
The apparatus of claim 1 wherein the means for hopping the radio frequency source hops between the pluralities of frequencies in a pseudo random manner.
Claim 5
Dependent Claim
16 words
The apparatus of claim 3 wherein the means for hopping includes a pseudo random code generator.
Claim 6
Dependent Claim
68 words
The apparatus of claim 4 wherein the pseudo random code generator includes a first pseudo random code including a plurality of code entries; and a timing circuit receiving as an input a clock signal, the timing circuit controlling the sequential outputting of the code entries in the first pseudo random code, the outputted code entries controlling the frequency at which the radio frequency source outputs the interrogation signal.
Claim 7
Dependent Claim
64 words
The apparatus of claim 1 wherein the frequency range is divided into a plurality of bins, each of which defines a sub-range of frequencies; and the controller includes a bin selector for selecting one of the plurality of bins such that the interrogation signal is outputted at a frequency within a sub-range of frequencies associated with the selected one of the plurality of bins.
Claim 8
Dependent Claim
23 words
The apparatus of claim 6 wherein the radio frequency source hops between frequencies in the sub-ranges of frequencies in a pseudo random manner.
Claim 9
Dependent Claim
39 words
The apparatus of claim 7 wherein the means for hopping the radio frequency source further includes a pseudo random code generator, the pseudo random code generator outputting a code entry for selecting a frequency within the sub-range of frequencies.
Claim 10
Dependent Claim
49 words
The apparatus of claim 6 further including means for guarding against transmissions outside the frequency range including guard bands at each end of the frequency range; and wherein the interrogation signal has a first bandwidth and the guard bands are at least half as wide as the first bandwidth.
Claim 11
Dependent Claim
25 words
The apparatus of claim 6 wherein the frequency range includes one or more guard bands, the guard bands separating adjacent bins in the frequency range.
Claim 12
Dependent Claim
34 words
The apparatus of claim 1 further including means for adjusting a dwell time at which the radio frequency source remains at a first frequency before hopping to a next frequency in the frequency range.
Claim 13
Dependent Claim
25 words
The apparatus of claim 5 further including means for outputting a non sequential code entry in the first pseudo random code upon a predetermined condition.
Claim 14
Dependent Claim
28 words
The apparatus of claim 12 further including means for detecting interference with another radio frequency source, and where the predetermined condition includes interference with another radio frequency source.
Claim 15
Dependent Claim
39 words
The apparatus of claim 1 further including means for selecting sequential code entries from a second sequence upon a predetermined condition, and for selecting sequential code entries from the first sequence upon a next occurrence of the predetermined condition.
Claim 16
Dependent Claim
16 words
The apparatus of claim 14 wherein the predetermined condition includes interference with another radio frequency source.
Claim 17
Dependent Claim
21 words
The apparatus of claim 1 wherein the controller operates to vary the hopping by varying a dwell time for the reader.
Claim 18
Dependent Claim
27 words
The apparatus of claim 1 wherein the controller operates to vary the hopping by initiating a non-sequential hop in the first sequence upon detection of destructive interference.
Claim 19
Dependent Claim
26 words
The apparatus of claim 1 wherein the controller operates to vary the hopping by initiating hopping according to a second sequence upon detection of destructive interference.
Claim 20
Dependent Claim
55 words
The apparatus of claim 1 wherein the frequency range is divided into a plurality of bins; and the controller includes a bin selector operable to cause the radio frequency source to output a plurality of frequencies within a selected bin and wherein the controller operates to vary the hopping by enabling a new bin selection.
Claim 21
Dependent Claim
97 words
A reader for reading data from an electronic tag comprising: a bi-directional antenna; a frequency hopping source for generating an interrogation signal at a frequency within a frequency range according to a first sequence; a homodyne radio for transmitting the interrogation signal to the electronic tag through the antenna and for receiving a radio frequency signal returned from the electronic tag; means for processing the radio frequency signal to decode the data from the electronic tag; and a controller operating to vary the hopping of the frequency hopping source to minimize occurrences of interference among adjacent readers.
Claim 22
Dependent Claim
97 words
A reader for reading data from an electronic tag comprising: a bi-directional antenna; a frequency hopping source for generating an interrogation signal at a frequency within a frequency range according to a first sequence; a homodyne radio for transmitting the interrogation signal to the electronic tag through the antenna and for receiving a radio frequency signal returned from the electronic tag; means for processing the radio frequency signal to decode the data from the electronic tag; and a controller operating to vary the hopping of the frequency hopping source to minimize occurrences of interference among adjacent readers.
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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) | 2001-10-26 | 2002-04-27 | 2002-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-10-26 | 2006-04-27 | 2006-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-10-26 | 2010-04-27 | 2010-10-27 | $7700.00 | Window Closed / Lapsed |