US3717756A
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US
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High precision circulating digital correlator
Assignee: ELECTRONIC COMMUNICATIONS
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Filing: 1970-10-30
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Granted: 1973-02-20
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Expires: 1990-10-30
Abstract
Abstract A digital correlator of high precision and relative simplicity includes a pair of circulating memories, a multiplier and an accumulator. The input signal to be studied is sampled to produce a series of binary samples which are stored in one of the memories. The correlation coefficients of the input signal are computed by forming the products of the samples and summing those products to the corresponding correlation coefficients previously stored in the other memory, to thereby update the coefficients during each sampling of the input signal.
Inventors
- 👤 J Stitt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 05:41
CPC Classifications
G; G06; G06F; G06F17/00; G06F17/10; G06F17/15
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
210 words
A system for deriving the correlation function of an input analog signal comprising means for sampling said input signal at a predetermined rate and for sequentially producing a binary sample representative of the analog value of said input signal at the time of sampling, first k-stage circulating memory means respectively storing in its stages the k previously obtained binary samples, second k-stage circulating memory means respectively storing in its stages a set of previously computed k correlation coefficients, product forming means coupled to the output of said sampling means and the input stage of said first memory means for initially forming the product of the most recent sampled binary signal with itself, and thereafter with each of said binary samples stored in said first memory means, and means coupled to t2 output of said product forming means having first and second inputs couPled respectively to the output stage of said second memory means and to the output of said product forming means, and an output coupled to the input stage of said second memory means, for respectively summing said products with corresponding ones of said stored correlation coefficients, to thereby update said correlation coefficients, and respectively restore the thus updated correlation coefficients into the stages of said second memory means.
Claim 2
Independent Claim
210 words
A system for deriving the correlation function of an input analog signal comprising means for sampling said input signal at a predetermined rate and for sequentially producing a binary sample representative of the analog value of said input signal at the time of sampling, first k-stage circulating memory means respectively storing in its stages the k previously obtained binary samples, second k-stage circulating memory means respectively storing in its stages a set of previously computed k correlation coefficients, product forming means coupled to the output of said sampling means and the input stage of said first memory means for initially forming the product of the most recent sampled binary signal with itself, and thereafter with each of said binary samples stored in said first memory means, and means coupled to t2 output of said product forming means having first and second inputs couPled respectively to the output stage of said second memory means and to the output of said product forming means, and an output coupled to the input stage of said second memory means, for respectively summing said products with corresponding ones of said stored correlation coefficients, to thereby update said correlation coefficients, and respectively restore the thus updated correlation coefficients into the stages of said second memory means.
Claim 3
Independent Claim
210 words
A system for deriving the correlation function of an input analog signal comprising means for sampling said input signal at a predetermined rate and for sequentially producing a binary sample representative of the analog value of said input signal at the time of sampling, first k-stage circulating memory means respectively storing in its stages the k previously obtained binary samples, second k-stage circulating memory means respectively storing in its stages a set of previously computed k correlation coefficients, product forming means coupled to the output of said sampling means and the input stage of said first memory means for initially forming the product of the most recent sampled binary signal with itself, and thereafter with each of said binary samples stored in said first memory means, and means coupled to t2 output of said product forming means having first and second inputs couPled respectively to the output stage of said second memory means and to the output of said product forming means, and an output coupled to the input stage of said second memory means, for respectively summing said products with corresponding ones of said stored correlation coefficients, to thereby update said correlation coefficients, and respectively restore the thus updated correlation coefficients into the stages of said second memory means.
Claim 4
Independent Claim
210 words
A system for deriving the correlation function of an input analog signal comprising means for sampling said input signal at a predetermined rate and for sequentially producing a binary sample representative of the analog value of said input signal at the time of sampling, first k-stage circulating memory means respectively storing in its stages the k previously obtained binary samples, second k-stage circulating memory means respectively storing in its stages a set of previously computed k correlation coefficients, product forming means coupled to the output of said sampling means and the input stage of said first memory means for initially forming the product of the most recent sampled binary signal with itself, and thereafter with each of said binary samples stored in said first memory means, and means coupled to t2 output of said product forming means having first and second inputs couPled respectively to the output stage of said second memory means and to the output of said product forming means, and an output coupled to the input stage of said second memory means, for respectively summing said products with corresponding ones of said stored correlation coefficients, to thereby update said correlation coefficients, and respectively restore the thus updated correlation coefficients into the stages of said second memory means.
Claim 5
Dependent Claim
80 words
The system of claim 1, in which said product forming means includes first and second inputs, switching means alternately operable in first and second positions coupled to said product forming means for applying when in said first position said recently produced binary sample to said first and second inputs of said product forming means, and when in said second position for sequentially applying the contents of said first memory means to one of said inputs of said product forming means.
Claim 6
Dependent Claim
54 words
The system of claim 2, further comprising means for selectively operating said switching means in its said first and second positions, and for sequentially transferring the contents of said first and second memory means to said product forming means and said summing means respectively when said switching means is in its said second position.
Claim 7
Dependent Claim
50 words
The system of claim 3, in which said first and second memory means comprises a K-word MOS circulating memory, wherein K is an integer equal to the number of correlation coefficients stored in said second memory means and is independent of the number of samples taken of said input signal.
Claim 8
Dependent Claim
186 words
A digital filter system for deriving a predetermined function of an input signal comprising means for sampling said input signal and for producing a plurality of binary samples representative of said input signal, m-stage first circulating memory means respectively storing a plurality of filter coefficient reference signals in its stages, m-stage second circulating memory means respectively storing previously computed partial sums in its stages, means having first and second inputs respectively coupled to said sampling means and to the input stage of said first circulating means for selectively and sequentially forming the products of each of said sampled binary signals with predetermined ones of said coefficient signals stored in said first memory means, and means having first and second inputs coupled to the output of said product forming means and the output stage of said second memory means, and an output coupled to the input stage of said second memory means for respectively summing the thus-formed products with the partial sum signals stored in said second memory means, to thereby form the desired correlation function of the input signal of the output of said summing means.
Claim 9
Dependent Claim
186 words
A digital filter system for deriving a predetermined function of an input signal comprising means for sampling said input signal and for producing a plurality of binary samples representative of said input signal, m-stage first circulating memory means respectively storing a plurality of filter coefficient reference signals in its stages, m-stage second circulating memory means respectively storing previously computed partial sums in its stages, means having first and second inputs respectively coupled to said sampling means and to the input stage of said first circulating means for selectively and sequentially forming the products of each of said sampled binary signals with predetermined ones of said coefficient signals stored in said first memory means, and means having first and second inputs coupled to the output of said product forming means and the output stage of said second memory means, and an output coupled to the input stage of said second memory means for respectively summing the thus-formed products with the partial sum signals stored in said second memory means, to thereby form the desired correlation function of the input signal of the output of said summing means.
Claim 10
Dependent Claim
41 words
The system of claim 5, further comprising a source of said reference signals, and switch means coupled to said source and said first memory means, and effective when in one position to transfer said reference signals into said first memory means.
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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) | 1976-02-20 | 1976-08-21 | 1977-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-20 | 1980-08-21 | 1981-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-20 | 1984-08-21 | 1985-02-20 | $7700.00 | Window Closed / Lapsed |