US3676565A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Time domain waveform synthesizing method
Assignee: Singer Co
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Filing: 1970-12-01
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Granted: 1972-07-11
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Expires: 1990-12-01
Abstract
Abstract A method of synthesizing time domain waveforms from data in the frequency domain with improved resolution in the middle and lower frequencies. Frequency data is broken down into groups and each group processed through an inverse Fourier or fast Fourier transform to obtain time domain data which is then added together in the proper time relationship. The resulting composite digital information is then passed through a digital to analog converter to provide an analog time domain waveform.
Inventors
- 👤 John Joseph Rowe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:00
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/02; G01S7/40; G01R; G01R23/00; G01R23/16
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
134 words
A method of transforming frequency domain data to time domain data with improved resolution in the middle and lower frequencies comprising: a. segregating the frequency domain data into groups, each group containing a range of frequencies which is a portion of the total frequency range and storing said groups in a digital computer; b. individually processing each group, in the computer, through an inverse Fourier transform to obtain groups of time domain data, the processing rate of each group being such that for a constant period of time data will be available for the total period from all groups, and storing said time domain data in said computer; and c. adding the time domain data from each of said groups to the other in the proper time sequence to obtain composite time domain data.
Claim 2
Independent Claim
134 words
A method of transforming frequency domain data to time domain data with improved resolution in the middle and lower frequencies comprising: a. segregating the frequency domain data into groups, each group containing a range of frequencies which is a portion of the total frequency range and storing said groups in a digital computer; b. individually processing each group, in the computer, through an inverse Fourier transform to obtain groups of time domain data, the processing rate of each group being such that for a constant period of time data will be available for the total period from all groups, and storing said time domain data in said computer; and c. adding the time domain data from each of said groups to the other in the proper time sequence to obtain composite time domain data.
Claim 3
Dependent Claim
133 words
The invention according to claim 1 wherein the total frequency range is a to bxn, where a is the lowest and bxn the highest frequency, x a multiple between groups, and n represents the number of groups plus 1, and the individual groups are a to b, ax to bx---axn 1 to bxn 1 and axn to bxn; wherein the group axn to bxn is processed xn times, axn 1 is processed xn 1 time, and ax to bx is processed x times each time a to b is processed once; and wherein one word of said a to b group is added to x words of said ax to bx group and likewise one word of each successive group to x words of the following group to obtain said time domain data.
Claim 4
Dependent Claim
35 words
The invention according to claim 1 and further including the steps or providing the resulting composite time domain data in increments to a digital to analog converter to obtain a real time domain wave form.
Claim 5
Dependent Claim
15 words
The invention according to claim 1 wherein said Fourier transform is a fast Fourier transform.
Claim 6
Dependent Claim
74 words
In a training device wherein sound data is presented to a trainee, a method of generating sound data in the time domain comprising; a. computing and storing frequency domain data relating to the sounds to be presented; b. passing said frequency domain data through an inverse Fourier transform to obtain time domain data; and c. sequentially presenting said time domain data to the training device to form a real time time domain wave form.
Claim 7
Dependent Claim
74 words
In a training device wherein sound data is presented to a trainee, a method of generating sound data in the time domain comprising; a. computing and storing frequency domain data relating to the sounds to be presented; b. passing said frequency domain data through an inverse Fourier transform to obtain time domain data; and c. sequentially presenting said time domain data to the training device to form a real time time domain wave form.
Claim 8
Dependent Claim
29 words
The invention according to claim 5 wherein said time domain data is computed in digital form and converted to an analog form prior to presentation to said training device.
Claim 9
Dependent Claim
50 words
The invention according to claim 5 and further including the steps of breaking said frequency domain data into groups prior to passing said data through said transform and adding the resulting time domain data after passing through said transform whereby the resolution at middle and lower frequencies will be improved.
References Cited (Backward Citations)
US3517173A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-11 | 1976-01-10 | 1976-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-11 | 1980-01-10 | 1980-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-11 | 1984-01-10 | 1984-07-11 | $7700.00 | Window Closed / Lapsed |