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Signal identification system

Assignee: MEDIAGUIDE HOLDINGS LLC
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Filing: 1989-10-25
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Granted: 1992-05-12
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Expires: 2009-10-25
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Abstract

Abstract A signal identification system, suitable for producing an identification code on a sound track recording is described. The system includes an encoder 209 effective to eliminate a variable sequence of frequency bands from an audio signal and insert a sequence of code signals into the frequency bands. As the sequence of frequency bands varies throughout the sound track recording, the presence of the code is difficult to detect.

Inventors

  • 👤 Stuart J. Best
  • 👤 Nigel Johnson
  • 👤 Adrian M. Sandford

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 12:19
CPC Classifications
H; H04; H04H; H04H20/00; H04H20/28; H04H20/30; H04H20/31; G; G11; G11B; G11B20/00; G11B20/00086; G11B20/00884; G11B20/00891

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 138 words
A signal identification system comprising: encoding means comprising means for choosing a variable sequence of frequency bands from a plurality of different predetermined frequency bands in the bandwidth of a given signal; means for eliminating the chosen sequence of frequency bands from the given signal to form a sequence of corresponding notches in the given signal; and means for inserting a sequence of code signals into the notches, each code signal comprising frequencies within the bandwidth of the notch or notches into which it is inserted; and decoding means including delay means adapted to delay the insertion of the code signals into the notches until the decoding means ascertains that the amplitude of the code signal is sufficient to be detectable within the given signal, and to determine whether the code signal is present in the given signal.
Claim 2
Dependent Claim 138 words
A signal identification system comprising: encoding means comprising means for choosing a variable sequence of frequency bands from a plurality of different predetermined frequency bands in the bandwidth of a given signal; means for eliminating the chosen sequence of frequency bands from the given signal to form a sequence of corresponding notches in the given signal; and means for inserting a sequence of code signals into the notches, each code signal comprising frequencies within the bandwidth of the notch or notches into which it is inserted; and decoding means including delay means adapted to delay the insertion of the code signals into the notches until the decoding means ascertains that the amplitude of the code signal is sufficient to be detectable within the given signal, and to determine whether the code signal is present in the given signal.
Claim 3
Dependent Claim 28 words
A system according to claim 1 in which there are at least three different predetermined frequency bands, each code signal comprising frequencies within two different predetermined frequency bands.
Claim 4
Dependent Claim 25 words
A system according to claim 2 in which the code signals within each of the two different predetermined frequency values represent respective different binary values.
Claim 5
Dependent Claim 29 words
A system according to claim 1 in which the decoding means further includes means for inspecting all possible combinations of the predetermined frequency bands in a given signal simultaneously.
Claim 6
Dependent Claim 33 words
A system according to claim 1 in which the variable sequence is a predetermined sequence and the decoding system includes means for inspecting predetermined frequency bands in the order of the predetermined sequence.
Claim 7
Dependent Claim 89 words
An encoding system for the coding of a given signal comprising: means for choosing a variable sequence of frequency bands from a plurality of different predetermined frequency bands in the bandwidth of a given signal; means for eliminating the sequence of chosen frequency bands from the given signal to form a sequence of corresponding notches in the given signal; and means for inserting a sequence of code signals into the notches, each code signal comprising frequencies within the bandwidth of the notch or notches into which it is inserted.
Claim 8
Dependent Claim 89 words
An encoding system for the coding of a given signal comprising: means for choosing a variable sequence of frequency bands from a plurality of different predetermined frequency bands in the bandwidth of a given signal; means for eliminating the sequence of chosen frequency bands from the given signal to form a sequence of corresponding notches in the given signal; and means for inserting a sequence of code signals into the notches, each code signal comprising frequencies within the bandwidth of the notch or notches into which it is inserted.
Claim 9
Dependent Claim 28 words
A system according to claim 6 in which there are at least three different predetermined frequency bands, each code signal comprising frequencies within two different predetermined frequency bands.
Claim 10
Independent Claim 25 words
A system according to claim. 7 in which the code signals within each of the two different predetermined frequency values represent respective different binary values.
Claim 11
Dependent Claim 34 words
A system according to claim 6 in which the encoding means includes means for inhibiting the- insertion of the code signal into the notches where the code signal is not likely to be detectable.
Claim 12
Dependent Claim 42 words
A decoding system for decoding a signal in which a code signal has been incorporated in a variable sequence of predetermined frequency bands in the signal, the decoding system including means for inspecting a plurality of combinations of the predetermined frequency bands.
Claim 13
Dependent Claim 42 words
A decoding system for decoding a signal in which a code signal has been incorporated in a variable sequence of predetermined frequency bands in the signal, the decoding system including means for inspecting a plurality of combinations of the predetermined frequency bands.

References Cited (Backward Citations)

US4156205A Cited
US4325089A Cited
EP0135192A2 Cited
EP0245037A2 Cited
US4876617A Cited
US4802212A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-05-12 1995-11-11 1996-05-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-05-12 1999-11-11 2000-05-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-05-12 2003-11-11 2004-05-12 $7700.00 Window Closed / Lapsed

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