US5530601A
Expired / Lapsed
US
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Tracking threshold circuit for peak detection
Assignee: International Business Machines Corp
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Filing: 1993-09-30
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Granted: 1996-06-25
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Expires: 2013-09-30
Abstract
Abstract A method and apparatus for detecting peaks in a signal which comprises an alternating polarity waveform including a plurality of points. A selected point in the signal is designated. Thereafter, a threshold value for the selected point is established utilizing a prior threshold value associated set off with spaces with a point prior to the selected point as follows: (m(n)=t0*ax(n)+t1*m(n-1) wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point. In this manner the threshold value may be adjusted for fluctuations in amplitude of the signal. Next, the selected point is compared with the threshold value to determine whether or not the selected point is within a predetermined distance of the threshold. If the selected point is within the predetermined distance of the threshold value, a determination is made as to whether or not the selected point represents a peak in order to ascertain the presence of a logic one at the selected point, wherein digital data may be detected in a signal.
Inventors
- 👤 Robert A. Hutchins
- 👤 Ara S. Patapoutian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:24
CPC Classifications
H; H04; H04L; H04L25/00; H04L25/02; H04L25/06; H04L25/061; H04L25/062; G; G11; G11B; G11B20/00; G11B20/10; G11B20/10009; G11B5/00; G11B5/02; G11B5/09
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
179 words
A method for detecting peaks in a signal which comprises an alternating polarity waveform having a plurality of points, said method comprising; designating a selected point from said plurality of points in said signal; establishing a threshold value for said selected point utilizing a prior threshold value associated with a point prior to said selected point as follows: m(n)=t0*ax(n)+t1*m(n-1) wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point, wherein said threshold value may be adjusted for fluctuations in said signal; comparing said selected point with said threshold value to determine if said selected point is within a selected distance of said threshold; and if said selected point is within said selected distance of said threshold value, determining whether said selected point represents a peak to ascertain the presence of a logic one at said selected point, wherein digital data.
Claim 2
Independent Claim
179 words
A method for detecting peaks in a signal which comprises an alternating polarity waveform having a plurality of points, said method comprising; designating a selected point from said plurality of points in said signal; establishing a threshold value for said selected point utilizing a prior threshold value associated with a point prior to said selected point as follows: m(n)=t0*ax(n)+t1*m(n-1) wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point, wherein said threshold value may be adjusted for fluctuations in said signal; comparing said selected point with said threshold value to determine if said selected point is within a selected distance of said threshold; and if said selected point is within said selected distance of said threshold value, determining whether said selected point represents a peak to ascertain the presence of a logic one at said selected point, wherein digital data.
Claim 3
Dependent Claim
7 words
The method of claim 1, wherein t0=1-t1
Claim 4
Dependent Claim
7 words
The method of claim 1, wherein: t0<1-t1
Claim 5
Dependent Claim
7 words
The method of claim 1, wherein: t0>1-t1
Claim 6
Dependent Claim
16 words
The method of claim 1, wherein t0 is determined by requirements of a tape drive system.
Claim 7
Independent Claim
217 words
A method for detecting peaks in a signal which comprises an alternating polarity waveform having a plurality of points, said method comprising; designating a selected point from said plurality of points in said signal; establishing a threshold value for said selected point utilizing a prior threshold value associated with a point prior to said selected point as follows: m(n)=t0*ax(n)+t1*m(n-1) wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point, wherein said threshold value may be adjusted for fluctuations in said signal; comparing said selected point with said threshold value to determine if said selected point is within a selected distance of said threshold; and if said selected point is within said selected distance of said threshold value, determining whether said selected point represents a peak to ascertain the presence of a logic one at said selected point, wherein said determining step further includes comparing said selected point with a preselected value and skipping said determining step if said selected point is not within a second distance from said preselected value, wherein digital data in a signal is detected.
Claim 8
Independent Claim
217 words
A method for detecting peaks in a signal which comprises an alternating polarity waveform having a plurality of points, said method comprising; designating a selected point from said plurality of points in said signal; establishing a threshold value for said selected point utilizing a prior threshold value associated with a point prior to said selected point as follows: m(n)=t0*ax(n)+t1*m(n-1) wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point, wherein said threshold value may be adjusted for fluctuations in said signal; comparing said selected point with said threshold value to determine if said selected point is within a selected distance of said threshold; and if said selected point is within said selected distance of said threshold value, determining whether said selected point represents a peak to ascertain the presence of a logic one at said selected point, wherein said determining step further includes comparing said selected point with a preselected value and skipping said determining step if said selected point is not within a second distance from said preselected value, wherein digital data in a signal is detected.
Claim 9
Independent Claim
220 words
A method for detecting logical data from a signal, said method comprising; reading data from a data source and creating a signal from said data, wherein said signal is an alternating polarity waveform comprising a plurality of points; designating a selected point from said plurality of points in said signal; establishing a threshold value for said selected point utilizing a prior threshold value associated with a point prior to said selected point as follows: m(n)=t0*ax(n)+t1*m(n-1) wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point, wherein said threshold value may be adjusted for fluctuations in said signal; comparing said selected point with said threshold value to determine if said selected point is within a selected distance of said threshold; if said selected point is within said selected distance of said threshold value, determining whether said selected point represents a peak to ascertain the presence of a logic one at said selected point; and producing logic one and logic zero data in response to a presence and absence of logic ones in said signal, wherein binary data in said signal is detected.
Claim 10
Independent Claim
220 words
A method for detecting logical data from a signal, said method comprising; reading data from a data source and creating a signal from said data, wherein said signal is an alternating polarity waveform comprising a plurality of points; designating a selected point from said plurality of points in said signal; establishing a threshold value for said selected point utilizing a prior threshold value associated with a point prior to said selected point as follows: m(n)=t0*ax(n)+t1*m(n-1) wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point, wherein said threshold value may be adjusted for fluctuations in said signal; comparing said selected point with said threshold value to determine if said selected point is within a selected distance of said threshold; if said selected point is within said selected distance of said threshold value, determining whether said selected point represents a peak to ascertain the presence of a logic one at said selected point; and producing logic one and logic zero data in response to a presence and absence of logic ones in said signal, wherein binary data in said signal is detected.
Claim 11
Independent Claim
196 words
An apparatus for detecting peaks in a signal which comprises an alternating polarity waveform having a plurality of points, said apparatus comprising; designation means for designating a selected point from said plurality of points in said signal; establishment means for establishing a threshold value for said selected point utilizing a prior threshold value associated with a point prior to said selected point as follows: m(n)=t0*ax(n)+t1*m(n-1) wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point, wherein said threshold value may be adjusted for fluctuations in said signal; comparison means for comparing said selected point with said threshold value to determine if said selected point is within a selected distance of said threshold; and determination means for determining whether said selected point represents a peak to ascertain the presence of a logic one at said selected point, if said selected point is within said selected distance of said threshold value, wherein digital data in a signal is detected.
Claim 12
Independent Claim
196 words
An apparatus for detecting peaks in a signal which comprises an alternating polarity waveform having a plurality of points, said apparatus comprising; designation means for designating a selected point from said plurality of points in said signal; establishment means for establishing a threshold value for said selected point utilizing a prior threshold value associated with a point prior to said selected point as follows: m(n)=t0*ax(n)+t1*m(n-1) wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point, wherein said threshold value may be adjusted for fluctuations in said signal; comparison means for comparing said selected point with said threshold value to determine if said selected point is within a selected distance of said threshold; and determination means for determining whether said selected point represents a peak to ascertain the presence of a logic one at said selected point, if said selected point is within said selected distance of said threshold value, wherein digital data in a signal is detected.
Claim 13
Dependent Claim
12 words
The apparatus of claim 8, wherein said signal is a digital signal.
Claim 14
Dependent Claim
12 words
The apparatus of claim 8, wherein said signal is an analog signal.
Claim 15
Dependent Claim
7 words
The apparatus of claim 8, wherein: t0=1-t1
Claim 16
Dependent Claim
7 words
The apparatus of claim 8, wherein: t0<1-t1
Claim 17
Dependent Claim
7 words
The apparatus of claim 8, wherein: t0>1-t1
Claim 18
Independent Claim
212 words
An apparatus for detecting peaks in a signal which comprises an alternating polarity waveform having a plurality of points, said apparatus comprising; designation means for designating a selected point from said plurality of points in said signal; establishment means for establishing a threshold value for said selected point utilizing a prior threshold value associated with a point prior to said selected point as follows: m(n)=t0*ax(n)+t1*m(n-1) wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point, wherein said threshold value may be adjusted for fluctuations in said signal; comparison means for comparing said selected point with said threshold value to determine if said selected point is within a selected distance of said threshold; and determination means for determining whether said selected point represents a peak to ascertain the presence of a logic one at said selected point, if said selected point is within said selected distance of said threshold value, wherein said determination means includes means for comparing said selected point with a preselected value and wherein digital data in a signal is detected.
Claim 19
Independent Claim
212 words
An apparatus for detecting peaks in a signal which comprises an alternating polarity waveform having a plurality of points, said apparatus comprising; designation means for designating a selected point from said plurality of points in said signal; establishment means for establishing a threshold value for said selected point utilizing a prior threshold value associated with a point prior to said selected point as follows: m(n)=t0*ax(n)+t1*m(n-1) wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point, wherein said threshold value may be adjusted for fluctuations in said signal; comparison means for comparing said selected point with said threshold value to determine if said selected point is within a selected distance of said threshold; and determination means for determining whether said selected point represents a peak to ascertain the presence of a logic one at said selected point, if said selected point is within said selected distance of said threshold value, wherein said determination means includes means for comparing said selected point with a preselected value and wherein digital data in a signal is detected.
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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) | 1999-06-25 | 1999-12-25 | 2000-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-06-25 | 2003-12-25 | 2004-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-06-25 | 2007-12-25 | 2008-06-25 | $7700.00 | Window Closed / Lapsed |