US3903401A
Expired / Lapsed
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Spectrum analyzer using delta modulation encoding
Assignee: AT&T Inc
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Filing: 1974-06-27
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Granted: 1975-09-02
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Expires: 1994-06-27
Abstract
Abstract Disclosed are a method and apparatus for computing the power spectrum of an applied analog signal at a chosen frequency, by converting the analog signal into a binary sequence, by separately multiplying the binary sequence by a sequence of cosine and sine functions, by accumulating and squaring the resultant product signals, by adding the squared signals, and by multiplying the added signals with a constant signal which is a function of the chosen frequency.
Inventors
- 👤 Nuggehally Sampath Jayant
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:36
CPC Classifications
G; G01; G01R; G01R23/00; G01R23/16
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
116 words
Apparatus for developing a signal representative of the power at a preselected frequency of a predtermined time segment of a delta modulated signal comprising: first means for multiplying said delta modulated signal with a cosine signal having its argument dependent on said preselected frequency; second means for multiplying said delta modulated signal with a sine signal having its argument identical to that of said cosine signal; third means for accumulating said first means output signal; sixth means for squaring said third means output signal; fourth means for accumulating said second means output signal; seventh means for squaring said fourth means output signal; and fifth means for adding the output signals of said sixth and seventh means.
Claim 2
Dependent Claim
116 words
Apparatus for developing a signal representative of the power at a preselected frequency of a predtermined time segment of a delta modulated signal comprising: first means for multiplying said delta modulated signal with a cosine signal having its argument dependent on said preselected frequency; second means for multiplying said delta modulated signal with a sine signal having its argument identical to that of said cosine signal; third means for accumulating said first means output signal; sixth means for squaring said third means output signal; fourth means for accumulating said second means output signal; seventh means for squaring said fourth means output signal; and fifth means for adding the output signals of said sixth and seventh means.
Claim 3
Dependent Claim
33 words
The apparatus of claim 1, further comprising: a multiplier for multiplying the output signal of said fifth means with a constant signal of a magnitude that is a function of said preselected frequency.
Claim 4
Dependent Claim
126 words
Apparatus for developing a signal representative of the power at a preselected frequency of a predetermined time segment of a delta modulated signal comprising: first means for multiplying said delta modulated signal with a trigonometric function comprising a difference of cosine signals having arguments dependent on said preselected frequency; second means for multiplying said delta modulated signal with a trigonometric function comprising a difference of sine signals having arguments identical to those of said cosine signals; third means for accumulating said first means output signal; fourth means for accumulating said second means output signal; fifth means for squaring said third means output signal; sixth means for squaring said fourth means output signal; and seventh means for adding the output signals of said first and sixth means.
Claim 5
Dependent Claim
126 words
Apparatus for developing a signal representative of the power at a preselected frequency of a predetermined time segment of a delta modulated signal comprising: first means for multiplying said delta modulated signal with a trigonometric function comprising a difference of cosine signals having arguments dependent on said preselected frequency; second means for multiplying said delta modulated signal with a trigonometric function comprising a difference of sine signals having arguments identical to those of said cosine signals; third means for accumulating said first means output signal; fourth means for accumulating said second means output signal; fifth means for squaring said third means output signal; sixth means for squaring said fourth means output signal; and seventh means for adding the output signals of said first and sixth means.
Claim 6
Dependent Claim
148 words
Apparatus for developing a signal representative of the power at a preselected frequency of a predetermined time segment of a delta modulated signal comprising: first means, for generating a difference of cosine signals having arguments dependent on said preselected frequency; second means, for generating a difference of sine signals having arguments identical to those of said cosine signals; third means for developing a first product signal of said delta modulated signal with said first means output signal; fourth means for developing a second product signal of said delta modulated signal with said second means output signal; fifth means for accumulating said first product signal; sixth means for accumulating said second product signal; seventh means for squaring the output signal of said fifth means; eighth means for squaring the output signal of said sixth means; and ninth means for adding the output signals of said seventh and eighth means.
Claim 7
Dependent Claim
148 words
Apparatus for developing a signal representative of the power at a preselected frequency of a predetermined time segment of a delta modulated signal comprising: first means, for generating a difference of cosine signals having arguments dependent on said preselected frequency; second means, for generating a difference of sine signals having arguments identical to those of said cosine signals; third means for developing a first product signal of said delta modulated signal with said first means output signal; fourth means for developing a second product signal of said delta modulated signal with said second means output signal; fifth means for accumulating said first product signal; sixth means for accumulating said second product signal; seventh means for squaring the output signal of said fifth means; eighth means for squaring the output signal of said sixth means; and ninth means for adding the output signals of said seventh and eighth means.
Claim 8
Dependent Claim
34 words
The apparatus of claim 4, further comprising a multiplier for multiplying the output signal of said means for adding with a constant signal of a magnitude that is a function of said preselected frequency.
Claim 9
Dependent Claim
190 words
Apparatus for developing a signal representative of the power at a preselected frequency of a preselected time segment of an applied signal comprising: a linear delta modulator responsive to said applied signal for generating a binary delta modulated signal; first means, for generating a difference of cosine signals having arguments dependent on said preselected frequency; second means, for generating a difference of sine signals having arguments identical to those of said cosine signals; a first multiplier for multiplying said delta modulated signals with said first means output signal; a second multiplier for multiplying said delta modulated signal with said second means output signal; a first accumulator for accumulating the output signal of said first multiplier; a second accumulator for accumulating the output signal of said second multiplier; third means for squaring the output signal of said first accumulator; fourth means for squaring the output signal of said second accumulator; fifth means for adding the output signals of said third and four means; and a multiplier for multiplying the output signal of said fifth means for adding with a constant signal having a magnitude that is a function of said frequency.
Claim 10
Dependent Claim
190 words
Apparatus for developing a signal representative of the power at a preselected frequency of a preselected time segment of an applied signal comprising: a linear delta modulator responsive to said applied signal for generating a binary delta modulated signal; first means, for generating a difference of cosine signals having arguments dependent on said preselected frequency; second means, for generating a difference of sine signals having arguments identical to those of said cosine signals; a first multiplier for multiplying said delta modulated signals with said first means output signal; a second multiplier for multiplying said delta modulated signal with said second means output signal; a first accumulator for accumulating the output signal of said first multiplier; a second accumulator for accumulating the output signal of said second multiplier; third means for squaring the output signal of said first accumulator; fourth means for squaring the output signal of said second accumulator; fifth means for adding the output signals of said third and four means; and a multiplier for multiplying the output signal of said fifth means for adding with a constant signal having a magnitude that is a function of said frequency.
Claim 11
Dependent Claim
18 words
The apparatus of claim 1 wherein said linear delta modulator''s binary output signal alternates between +1 and -1.
Claim 12
Dependent Claim
83 words
Apparatus for developing a signal representative of the power at a selected frequency, f, of a predetermined time segment of an applied signal comprising: a linear delta modulator of input step size Delta , responsive to an NT seconds segment of an applied signal and to a clock signal having a period T, developing a binary signal br having values +1 and -1, where r indicates the time position of br and ranges from 1 to N; a cosine generator providing a signal
Claim 13
Dependent Claim
83 words
Apparatus for developing a signal representative of the power at a selected frequency, f, of a predetermined time segment of an applied signal comprising: a linear delta modulator of input step size Delta , responsive to an NT seconds segment of an applied signal and to a clock signal having a period T, developing a binary signal br having values +1 and -1, where r indicates the time position of br and ranges from 1 to N; a cosine generator providing a signal
Claim 14
Dependent Claim
76 words
A spectrum analyzer tuned to a frequency f and responsive to an applied input signal of duration M seconds comprising: first means responsive to said applied input signal and to a clock signal having a period T seconds for developing a binary signal alternating between +1 and -1 where the integral of said binary signal forms a stepwise approximation of said applied input signal divided by a constant Delta ; means for generating first trigonometric signals
Claim 15
Dependent Claim
76 words
A spectrum analyzer tuned to a frequency f and responsive to an applied input signal of duration M seconds comprising: first means responsive to said applied input signal and to a clock signal having a period T seconds for developing a binary signal alternating between +1 and -1 where the integral of said binary signal forms a stepwise approximation of said applied input signal divided by a constant Delta ; means for generating first trigonometric signals
Claim 16
Independent Claim
176 words
The method of generating a power spectral estimate of an incoming signal at a preselected frequency comprising the steps of: converting a time segment of said incoming signal in accordance with linear delta modulation techniques into a sequence of N binary signals, br, having values + or - 1 at a rate of 1/T Hz, where r is a variable incrementing from 1 to N; multiplying each of said binary signals by a difference of cosine signals whose arguments are dependent on said preselected frequency and on said r variable to develop a sequence of N first signals; multiplying each of said binary signals by a difference of sine signals whose arguments are identical to those of said cosine signals to develop a sequence of N second signals; accumulating said sequence of N first signals; accumulating said sequence of N second signals; independently squaring the resultant signals of said two accumulating steps; adding said squared signals; and multiplying said added signals with a constant signal having a magnitude that is a function of said preselected frequency.
Claim 17
Independent Claim
176 words
The method of generating a power spectral estimate of an incoming signal at a preselected frequency comprising the steps of: converting a time segment of said incoming signal in accordance with linear delta modulation techniques into a sequence of N binary signals, br, having values + or - 1 at a rate of 1/T Hz, where r is a variable incrementing from 1 to N; multiplying each of said binary signals by a difference of cosine signals whose arguments are dependent on said preselected frequency and on said r variable to develop a sequence of N first signals; multiplying each of said binary signals by a difference of sine signals whose arguments are identical to those of said cosine signals to develop a sequence of N second signals; accumulating said sequence of N first signals; accumulating said sequence of N second signals; independently squaring the resultant signals of said two accumulating steps; adding said squared signals; and multiplying said added signals with a constant signal having a magnitude that is a function of said preselected frequency.
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) | 1978-09-01 | 1979-03-03 | 1979-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-01 | 1983-03-03 | 1983-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-01 | 1987-03-03 | 1987-09-02 | $7700.00 | Window Closed / Lapsed |