US4100369A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for numerically generating a wave which is phase modulated and which is free from unwanted modulation products
Assignee: Alcatel CIT SA
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Filing: 1976-08-19
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Granted: 1978-07-11
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Expires: 1996-08-19
Abstract
Abstract A digital device has an input for receiving successive samples of input data in digital form representative of phase values zeta . A sequence of the most recent input samples is stored in an input memory. A carrier phase source provides a signal representative of the phase theta of a carrier wave. A function memory stores values of a function ki x sin ( zeta n-i+ theta n) and is addressed by first selection means which select a group corresponding to a coefficient ki and second selection means which select a member of the group corresponding to the value of ( zeta + theta ). During a calculation period the sum of all values of the function is calculated for i varying between l and a predetermined number r. Each such sum forms a sample of the output wave which is converted to analogue form and filtered to remove unwanted sampling components.
Inventors
- 👤 Claude Stenstrom
- 👤 Christian Saint-Supery
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:52
CPC Classifications
H; H04; H04L; H04L27/00; H04L27/18; H04L27/20; H04L27/2032; H04L27/2092
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
153 words
Device for generating an output wave which is phase modulated and which is free from unwanted modulation products, said device receiving at a first frequency digital values representing the modulation phase to be applied to a carrier wave, and generating said output wave in the form of a sequence of digital values delivered at a second frequency, said device comprising: a source for delivering, at said second frequency, digital values representing the phase of the carrier wave to be modulated, delay means receiving said digital values representing the modulation phase for sampling them at said second frequency and for delivering, at each period of said second frequency, the digital values representing the modulation phase relative to the r preceding periods of said second frequency, a memory for storing r groups of digital values, corresponding to a given set of sinusoidal values multiplied by r predetermined coefficients k 1 to k r , respectively,
Claim 2
Dependent Claim
153 words
Device for generating an output wave which is phase modulated and which is free from unwanted modulation products, said device receiving at a first frequency digital values representing the modulation phase to be applied to a carrier wave, and generating said output wave in the form of a sequence of digital values delivered at a second frequency, said device comprising: a source for delivering, at said second frequency, digital values representing the phase of the carrier wave to be modulated, delay means receiving said digital values representing the modulation phase for sampling them at said second frequency and for delivering, at each period of said second frequency, the digital values representing the modulation phase relative to the r preceding periods of said second frequency, a memory for storing r groups of digital values, corresponding to a given set of sinusoidal values multiplied by r predetermined coefficients k 1 to k r , respectively,
Claim 3
Dependent Claim
132 words
address selection means for addressing said memory, said selection means being connected to said delay means and to said source for determining, at each period of said second frequency, r data items representative of the r respective sums of the values of the modulation phase for the r preceding periods and the value of the phase of the carrier for said each period, said memory delivering, in response to said r data items, r sinusoidal values corresponding to said r sums, multiplied respectively by k 1 to k r , and adding means for adding, on each period of said second frequency, the r values delivered by said memory, said coefficients k 1 to k r being equal to the weighting coefficients of a low-pass non-recursive filter having a given frequency response.
Claim 4
Dependent Claim
132 words
address selection means for addressing said memory, said selection means being connected to said delay means and to said source for determining, at each period of said second frequency, r data items representative of the r respective sums of the values of the modulation phase for the r preceding periods and the value of the phase of the carrier for said each period, said memory delivering, in response to said r data items, r sinusoidal values corresponding to said r sums, multiplied respectively by k 1 to k r , and adding means for adding, on each period of said second frequency, the r values delivered by said memory, said coefficients k 1 to k r being equal to the weighting coefficients of a low-pass non-recursive filter having a given frequency response.
Claim 5
Dependent Claim
70 words
A device according to claim 1, characterized in that said selection means comprises means for processing a signal which is representative of zero or non-zero, to within π, of the sums of the values of the modulation phase and of the value of the carrier phase; and means for applying this signal to said adding means, so as to block the addition each time one of the sums is zero.
Claim 6
Dependent Claim
23 words
A device according to claim 1, characterized in that said second frequency is equal to four times the frequency of the carrier wave.
Claim 7
Dependent Claim
123 words
A device according to claim 1, characterized in that the values of the r groups are preregistered in the memory at addresses each formed by two words, one of which words characterizes the group and the other of which characterizes the sinusoidal value concerned, and in that the selection means comprises two sub-assemblies, one of which is controlled by a rhythm signal for selecting sequentially, each at said second frequency, the r groups, and the other of which receives, at each sampling period of said second frequency, the r data items on the modulation phase delivered by the delay line and the data item concerning the phase of the carrier, to select the value to be read in each of the r groups.
Claim 8
Dependent Claim
23 words
A device according to claim 4, characterized in that said second frequency is equal to four times the frequency of the carrier wave.
Claim 9
Dependent Claim
70 words
A device according to claim 4, characterized in that said selection means comprises means for processing a signal which is representative of zero or non-zero, to within π, of the sums of the values of the modulation phase and of the value of the carrier phase; and means for applying this signal to said adding means, so as to block the addition each time one of the sums is zero.
Claim 10
Dependent Claim
23 words
A device according to claim 6, characterized in that said second frequency is equal to four times the frequency of the carrier wave.
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) | 1981-07-10 | 1982-01-09 | 1982-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-10 | 1986-01-09 | 1986-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-10 | 1990-01-09 | 1990-07-11 | $7700.00 | Window Closed / Lapsed |