US3763364A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for storing and reading out periodic waveforms
Assignee: Boeing North American Inc
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Filing: 1971-11-26
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Granted: 1973-10-02
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Expires: 1991-11-26
Abstract
Abstract The present invention is directed to a system for storing and reading out periodic waveshapes. The system utilizes the even and/or odd symmetry of a waveform in such a way that only sample points for one-half of the waveform need be stored in a memory device. When the waveform is read from the memory, the unstored sample points of the second half of the waveform are recreated, using the inherent symmetry of the stored samples of the waveform. The capacity of the memory storage device can then be cut in half, reducing substantially the cost of the system. If the desired periodic waveform is not symmetrical, it is converted into an equivalent waveform having an identical power spectrum but different phasing which created waveform is symmetrical. When such a created waveform is used to activate an audio device, the ear of the listener is unable to discern the difference between the desired waveform and the created one. This invention, therefore, has particular utility in electronic musical instruments.
Inventors
- 👤 R Deutsch
- 👤 R Ashby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:52
CPC Classifications
G; G10; G10H; G10H7/00; G10H7/08; G10H7/12; G06; G06F; G06F1/00; G06F1/02; G06F1/03; G06F1/035; G06F1/0353
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
76 words
Apparatus for creating periodic waveshapes comprising in combination: means for providing representation of sampled amplitude values of one-half cycle of a symmetrical waveform; utilization means; and means for addressing said providing means to feed said representations of sampled amplitude values tO said utilization means in a first order and then for addressing said providing means to feed said representations of sampled amplitude values to said utilization means in a second order opposite to said first order.
Claim 2
Dependent Claim
76 words
Apparatus for creating periodic waveshapes comprising in combination: means for providing representation of sampled amplitude values of one-half cycle of a symmetrical waveform; utilization means; and means for addressing said providing means to feed said representations of sampled amplitude values tO said utilization means in a first order and then for addressing said providing means to feed said representations of sampled amplitude values to said utilization means in a second order opposite to said first order.
Claim 3
Dependent Claim
25 words
The apparatus according to claim 1 wherein said addressing means addresses said providing means at selected rates to control the frequency of said periodic waveshape.
Claim 4
Dependent Claim
45 words
The apparatus according to claim 1 and further comprising: means interposed between the output of said providing means and the input of said utilization means for reversing the polarity of the provided representations of sampled amplitude values for said second order of said addressing means.
Claim 5
Dependent Claim
200 words
Apparatus for storing and reading periodic waveshapes comprising in combination: a memory for storing representations of sampled amplitude values of one-half cycle of an odd symmetrical waveform; means for addressing said memory in a first direction to read out said representations of stored amplitude values in a first order and for then addressing said memory in a second direction to read out said representations of stored amplitude values in a second order opposite to said first order; utilization means; first gate means for receiving the output from said memory and for feeding said output to said utilization means when said addressing means is operating in said first direction and for inhibiting said output when said addressing means is operating in said second direction; second gate means for receiving the output from said memory and for passing said output when said addressing means is operating in said second direction and for inhibiting said output when said addressing means is operating in said first direction; and complementary means for receiving the output of said second gate means and for inverting said output and for feeding said inverted signal to said utilizing means so as to complete one cycle of the symmetrical waveform.
Claim 6
Dependent Claim
200 words
Apparatus for storing and reading periodic waveshapes comprising in combination: a memory for storing representations of sampled amplitude values of one-half cycle of an odd symmetrical waveform; means for addressing said memory in a first direction to read out said representations of stored amplitude values in a first order and for then addressing said memory in a second direction to read out said representations of stored amplitude values in a second order opposite to said first order; utilization means; first gate means for receiving the output from said memory and for feeding said output to said utilization means when said addressing means is operating in said first direction and for inhibiting said output when said addressing means is operating in said second direction; second gate means for receiving the output from said memory and for passing said output when said addressing means is operating in said second direction and for inhibiting said output when said addressing means is operating in said first direction; and complementary means for receiving the output of said second gate means and for inverting said output and for feeding said inverted signal to said utilizing means so as to complete one cycle of the symmetrical waveform.
Claim 7
Dependent Claim
117 words
Apparatus for storing and reading periodic waveshapes comprising in combination: a memory for storing values corresponding to representations of amplitude samples of one-half of a cycle of a symmetrical waveform; means for addressing said memory in a first direction to read out the representations corresponding to the amplitude samples of the first half cycle of said symmetrical waveform; means for addressing said memory in a second direction opposite to said first direction to read out the representations corresponding to the amplitude samples of said first half cycle of said symmetrical waveform; and means for reversing the polarity of the representations read out in the second direction so as to form the complete cycle of the desired waveform.
Claim 8
Dependent Claim
117 words
Apparatus for storing and reading periodic waveshapes comprising in combination: a memory for storing values corresponding to representations of amplitude samples of one-half of a cycle of a symmetrical waveform; means for addressing said memory in a first direction to read out the representations corresponding to the amplitude samples of the first half cycle of said symmetrical waveform; means for addressing said memory in a second direction opposite to said first direction to read out the representations corresponding to the amplitude samples of said first half cycle of said symmetrical waveform; and means for reversing the polarity of the representations read out in the second direction so as to form the complete cycle of the desired waveform.
Claim 9
Dependent Claim
87 words
Apparatus for storing and reading periodic waveshapes comprising in combination: a memory for storing representations of sampled amplitude values of one-half cycle of a symmetrical waveform; means for addressing said memory in a first direction to read out said representations of stored amplitude values in a first order and for then addressing said memory in a second direction to read out said representations of stored amplitude values in a second order opposite to said first order; and utilization means for receiving the outputs from said memory means.
Claim 10
Dependent Claim
87 words
Apparatus for storing and reading periodic waveshapes comprising in combination: a memory for storing representations of sampled amplitude values of one-half cycle of a symmetrical waveform; means for addressing said memory in a first direction to read out said representations of stored amplitude values in a first order and for then addressing said memory in a second direction to read out said representations of stored amplitude values in a second order opposite to said first order; and utilization means for receiving the outputs from said memory means.
Claim 11
Dependent Claim
91 words
The apparatus according to claim 6 wherein said means for addressing is comprised of an up-down counter, the individual output stages of which are connected to corresponding storage positions in said memory; and an input control signal for commanding said up-down counter to count at a rate determined by said control signal so as to cause said up-down counter to address said memory in a first direction as the counter counts up and to cause said up-down counter to address said memory in an opposite direction as the counter counts down.
Claim 12
Dependent Claim
72 words
The apparatus according to claim 6 wherein said means for addressing said memory is comprised of a counter having a count capabiLity which is at least twice the number of stored values in said memory wherein said counter is connected to said memory such that the first half of said counter addresses said memory in a first direction and the second half of said counter addresses said memory in an opposite direction.
Claim 13
Dependent Claim
54 words
The apparatus according to claim 6 and further comprising: means interposed between the output of said memory and the input of said utilization means for reversing the polarity of the stored representations of sample amplitude values for one direction of said memory readout when the waveform stored in said memory is of odd symmetry.
Claim 14
Dependent Claim
29 words
The apparatus according to claim 6 wherein said representations of stored sampled amplitudes are digital words corresponding to the amplitude increments of said waveform at the successive sample points.
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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) | 1976-10-01 | 1977-04-02 | 1977-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-01 | 1981-04-02 | 1981-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-01 | 1985-04-02 | 1985-10-02 | $7700.00 | Window Closed / Lapsed |