Patent US3708748A successfully refreshed from Google Patents.
US3708748A
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Retrospective pulse modulation and apparatus therefor
Assignee: International Business Machines Corp
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Filing: 1970-04-27
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Granted: 1973-01-02
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Expires: 1990-04-27
Abstract
Abstract Digital data in self-timing reference is free from error due to irregular data spacing because of variations in speed and/or direction of scan in manual or machine applications with a pulse modulation of retrospective nature. Initially reference data manifestations are established and thereafter digital data are established partly on the basis of preceding manifestations of the data. In a binary data translating system, for example, a pair of reference pulses are spaced apart by a given interval. A binary unit is thereafter manifested by a pulse following at the same or similar interval and a binary zero is manifested by a pulse following at a differing interval. Each manifestation of a binary number thereafter depends on the interval between preceding pulses. A principle advantage of retrospective pulse modulation lies in demodulation. Large variations in the spacing and relatively larger variations in the scanning speed are accommodated readily. Magnetic tape and like records can not only be addressed at conventional high speeds in searching and at conventional low speeds later used in reproducing but, also can be searched continuously as the change is made between those speeds. Adaptive rate communications are particularly enhanced by the principle. Optical scanning of bar codes is improved by differing the spacing of uniform width bars or with bars of differing widths and differing spacing. These arrangements are applicable to railroad car and like object identifying, label data processing, human identification, card data processing, graphical display data probing systems and many other uses. Synchronous and asynchronous capability permits input to almost any digital data processing system.
Inventors
- 👤 E Nassimbene
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:27
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/10; G11B20/14; G11B20/1403; G11B20/1407; G11B20/1411; G06; G06F; G06F3/00; G06F3/01; G06F3/02; G06F3/0202; G06K; G06K7/00; G06K7/01; G06K7/016; G06K7/0166; H; H04; H04L; H04L25/00; H04L25/38; H04L25/40; H04L25/49
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
217 words
Retrospective pulse modulation encoding and decoding apparatus comprising, a pulse train generating circuit for producing substantially uniformly spaced pulses at the output terminals thereof, a modulating circuit having input terminals coupled to the output terminals of said generating circuit, output terminals and data input terminals, said modulating circuit being arranged for selectively varying the spacing of said pulses from said generating circuit as applied at said modulating circuit input terminals in response to the data applied at said data input terminals for delivering pulses spaced apart at said modulating circuit output terminals by a plurality of differing intervals with data of one nature represented by a plurality of pulses spaced apart by successive, equal intervals and data of another nature represented by a plurality of pulses spaced apart by successive, unequal intervals, measuring circuitry responsive to pulses emanating from the output terminals of said modulating circuit and having logical circuitry for measuring successive intervals between said emanating pulses, and comparing circuitry coupled to said measuring circuitry for comparing successive pairs of intervals with each interval after the first interval being compared with the preceding and thereafter the succeeding interval, and circuitry coupled to said comparing circuitry for interpreting equal pairs of intervals as information of one nature and unequal pairs of intervals as information of another nature.
Claim 2
Dependent Claim
217 words
Retrospective pulse modulation encoding and decoding apparatus comprising, a pulse train generating circuit for producing substantially uniformly spaced pulses at the output terminals thereof, a modulating circuit having input terminals coupled to the output terminals of said generating circuit, output terminals and data input terminals, said modulating circuit being arranged for selectively varying the spacing of said pulses from said generating circuit as applied at said modulating circuit input terminals in response to the data applied at said data input terminals for delivering pulses spaced apart at said modulating circuit output terminals by a plurality of differing intervals with data of one nature represented by a plurality of pulses spaced apart by successive, equal intervals and data of another nature represented by a plurality of pulses spaced apart by successive, unequal intervals, measuring circuitry responsive to pulses emanating from the output terminals of said modulating circuit and having logical circuitry for measuring successive intervals between said emanating pulses, and comparing circuitry coupled to said measuring circuitry for comparing successive pairs of intervals with each interval after the first interval being compared with the preceding and thereafter the succeeding interval, and circuitry coupled to said comparing circuitry for interpreting equal pairs of intervals as information of one nature and unequal pairs of intervals as information of another nature.
Claim 3
Dependent Claim
70 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 1 and incorporating rate determining circuitry coupled to said comparing circuitry for producing an output indicative of the efficacy of the translation of pulses from said comparing circuitry, and controlling circuitry coupled between rate determining circuitry and said generating circuit for varying the recurrence rate of said generating circuit in response to the output of said rate determining circuitry.
Claim 4
Dependent Claim
46 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 2 and wherein said rate determining and controlling circuitry are arranged for maximum recurrence rate in the absence of output from said rate determining circuitry and for reducing the recurrence rate as that output increases.
Claim 5
Dependent Claim
273 words
A retrospective pulse modulation communication system comprising, a pulse train generating circuit for producing electric pulses spaced apart in time at output terminals, and arranged for control of the spacing of said pulses by a control potential at control terminals of said generating circuit, a rate controlling circuit connected tO said generating circuit for producing said control potential in response to a control signal applied at control terminals of said controlling circuit, modulating circuitry having two input circuits and an output circuit, means connecting said output terminals of said generating circuit to one of said input circuits of said modulating circuitry, means for applying an information signal to the other of said input circuits of said modulating circuitry, said modulating circuitry being arranged for altering the spacing of said pulses by a plurality of intervals with each interval after the first interval associated with a preceding interval for representing elements of said characters in accordance with the information in said signal demodulating circuitry having an input circuit arranged for responding to said output circuit of said modulating circuitry and an output circuit, said demodulating circuitry responding to the spacing of said pulses by measuring successive intervals therebetween and comparing successive pairs of intervals with each interval after the first interval being compared with the preceding and thereafter the succeeding interval except for the last interval, utilization circuitry coupled to said demodulating circuitry, error detecting circuitry coupled to said demodulating circuitry, and circuitry coupled between said error detecting circuitry and said generating circuit for varying the rate of generation of said pulses inversely to the rate of errors detected by said error detecting circuitry.
Claim 6
Dependent Claim
273 words
A retrospective pulse modulation communication system comprising, a pulse train generating circuit for producing electric pulses spaced apart in time at output terminals, and arranged for control of the spacing of said pulses by a control potential at control terminals of said generating circuit, a rate controlling circuit connected tO said generating circuit for producing said control potential in response to a control signal applied at control terminals of said controlling circuit, modulating circuitry having two input circuits and an output circuit, means connecting said output terminals of said generating circuit to one of said input circuits of said modulating circuitry, means for applying an information signal to the other of said input circuits of said modulating circuitry, said modulating circuitry being arranged for altering the spacing of said pulses by a plurality of intervals with each interval after the first interval associated with a preceding interval for representing elements of said characters in accordance with the information in said signal demodulating circuitry having an input circuit arranged for responding to said output circuit of said modulating circuitry and an output circuit, said demodulating circuitry responding to the spacing of said pulses by measuring successive intervals therebetween and comparing successive pairs of intervals with each interval after the first interval being compared with the preceding and thereafter the succeeding interval except for the last interval, utilization circuitry coupled to said demodulating circuitry, error detecting circuitry coupled to said demodulating circuitry, and circuitry coupled between said error detecting circuitry and said generating circuit for varying the rate of generation of said pulses inversely to the rate of errors detected by said error detecting circuitry.
Claim 7
Dependent Claim
232 words
Retrospective pulse modulation encoding and decoding apparatus comprising, recording apparatus including a document retaining element, a document recording element, an advancement device coupled to said elements for positioning said recording element relative to said retaining element successively in a given direction in substantially uniform intervals, and mechanism for selectively activating and inhibiting said recording element in accordance with data to be recorded on a document retained by said retaining element in the form of manifestations spaced at a plurality of intervals with data of one nature denoted by successive intervals of equal spacing and data of another nature denoted by successive intervals of unequal spacing and each interval after the first interval being significant with respect to the preceding interval and with respect to the subsequent interval; and reproducing apparatus including a document scanning element arranged for movement over said document in said given direction and having output terminals delivering an electric wave manifesting successive intervals of corresponding equal and unequal spacing in accordance with the data that was recorded on said document, and circuitry coupled to said scanning element for measuring successive intervals of said wave and comparing successive pairs of said intervals with each interval after the first interval being compared with the preceding interval and with the succeeding interval except for the last interval for substantially equal and substantially unequal intervals on each comparison thereby for reproducing said data.
Claim 8
Dependent Claim
232 words
Retrospective pulse modulation encoding and decoding apparatus comprising, recording apparatus including a document retaining element, a document recording element, an advancement device coupled to said elements for positioning said recording element relative to said retaining element successively in a given direction in substantially uniform intervals, and mechanism for selectively activating and inhibiting said recording element in accordance with data to be recorded on a document retained by said retaining element in the form of manifestations spaced at a plurality of intervals with data of one nature denoted by successive intervals of equal spacing and data of another nature denoted by successive intervals of unequal spacing and each interval after the first interval being significant with respect to the preceding interval and with respect to the subsequent interval; and reproducing apparatus including a document scanning element arranged for movement over said document in said given direction and having output terminals delivering an electric wave manifesting successive intervals of corresponding equal and unequal spacing in accordance with the data that was recorded on said document, and circuitry coupled to said scanning element for measuring successive intervals of said wave and comparing successive pairs of said intervals with each interval after the first interval being compared with the preceding interval and with the succeeding interval except for the last interval for substantially equal and substantially unequal intervals on each comparison thereby for reproducing said data.
Claim 9
Dependent Claim
34 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 5 and wherein said mechanism includes means for initiating the recording by a pair of manifestations spaced apart by one of said intervals.
Claim 10
Dependent Claim
24 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 6 and wherein said initiating means are active before each character of information.
Claim 11
Dependent Claim
33 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 6 and wherein said initiating means are active for manifesting said pair of manifestations at one of at least two differing intervals.
Claim 12
Dependent Claim
29 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 6 and incorporating means for separating each character from the preceding and the succeeding characters in the series.
Claim 13
Dependent Claim
29 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 9 and wherein said separating means are active over an interval differing from either of said two intervals.
Claim 14
Dependent Claim
28 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 6 and wherein said initiating means are active for overlapping the final manifestation of any previous character.
Claim 15
Dependent Claim
29 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 6 and wherein said initiating means are active for overlapping the final two manifestations of any previous character.
Claim 16
Dependent Claim
26 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 5 and wherein said mechanism is active for manifesting characters of a minimum overall intervals.
Claim 17
Dependent Claim
26 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 13 and wherein said mechanism is active for manifesting characters of a uniform overall interval.
Claim 18
Dependent Claim
63 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 5 and wherein said recording apparatus is a printer for recording said data on a paper document in the form of printed bars arranged parallel to each other and spaced apart in said given direction, and said scanning element is an optical scanner with a photoelectric device for producing said electric wave.
Claim 19
Dependent Claim
53 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 15 and wherein said recording apparatus is a printer for recording said data in the form of bars of a plurality of widths, and said scanning element producers said electric wave in response to the sensing of both edges of said bars.
Claim 20
Dependent Claim
49 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 15 and wherein said recording apparatus is a magnetic transducer for recording said data on a magnetic record document in the form of transitions of a plurality of magnetic domains and said scanning element is an electromagnetic transducer.
Claim 21
Dependent Claim
25 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 17 and wherein said magnetic record document is in the form of magnetic tape.
Claim 22
Dependent Claim
31 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 17 and wherein said magnetic record document is in the form of a magnetic stripe laid down on a substrate.
Claim 23
Dependent Claim
47 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 5 and wherein said recording apparatus is a punch for recording said data in the form of apertures spaced apart in said document, and said scanning element includes electric contact devices for producing said electric wave.
Claim 24
Dependent Claim
46 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 5 and wherein said recording apparatus is a punch for recording said in the form of apertures spaced apart in said document, and said scanning element includes a photosensitive device for producing said electric wave.
Claim 25
Dependent Claim
43 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 5 and wherein said scanning element is arranged for movement over said document at a speed independent of the rate of recording of information on said document for producing said electric wave.
Claim 26
Dependent Claim
45 words
Retrospective pulse modulation encoding and decoding apparatus as defined in claim 5 and wherein said recording apparatus includes a character set prerecorded on another document and scanning element for recording said data on the first said document by selecting characters as desired from said set.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-02 | 1976-07-03 | 1977-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-02 | 1980-07-03 | 1981-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-02 | 1984-07-03 | 1985-01-02 | $7700.00 | Window Closed / Lapsed |