US3891929A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acoustic surface wave frequency synthesizer
Assignee: United States Department of the Air Force
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Filing: 1974-01-14
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Granted: 1975-06-24
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Expires: 1994-01-14
Abstract
Abstract Frequency synthesis is achieved by combining selected outputs from a multiplicity of acoustic surface wave filters. Each filter has a different filter pass frequency and in combination they define, in equal frequency increments, a given frequency. In a preferred embodiment the filters are fabricated as multiple parallel contiguous acoustic surface wave transmission channels on the propagating surface of a single piezoelectric substrate member. Input and output transducers are thinned interdigital electrodes with the output transducers being apodized in some instances. The filter outputs are fed to a switching matrix the output of which is controlled or coded by a number generator.
Inventors
- 👤 Paul H Carr
- 👤 Alan J Budreau
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:28
CPC Classifications
H; H03; H03B; H03B19/00; H03H; H03H9/00; H03H9/74; H03H9/76
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
107 words
An acoustic surface wave frequency synthesizer comprising a multiplicity of acoustic surface wave filters, each filter having an electromagnetic wave to acoustic surface wave input transducer and an acoustic surface wave to electromagnetic wave output transducer, a pulsed source of electromagnetic wave energy connected to supply, simultaneously, electromagnetic wave pulses to each filter input transducer, a system clock connected to said source of electromagnetic wave energy, a switching matrix having an output and multiple inputs, each filter output transducer being connected to a separate switch matrix input, and a switching matrix control means, said control means being connected to said switching matrix and to said system clock.
Claim 2
Dependent Claim
107 words
An acoustic surface wave frequency synthesizer comprising a multiplicity of acoustic surface wave filters, each filter having an electromagnetic wave to acoustic surface wave input transducer and an acoustic surface wave to electromagnetic wave output transducer, a pulsed source of electromagnetic wave energy connected to supply, simultaneously, electromagnetic wave pulses to each filter input transducer, a system clock connected to said source of electromagnetic wave energy, a switching matrix having an output and multiple inputs, each filter output transducer being connected to a separate switch matrix input, and a switching matrix control means, said control means being connected to said switching matrix and to said system clock.
Claim 3
Dependent Claim
136 words
An acoustic surface wave frequency synthesizer comprising a single piezoelectric substrate member having an acoustic surface wave propagating surface, said propagating surface being divided into multiple parallel contiguous acoustic surface wave transmission channels, each transmission channel having an electromagnetic wave to acoustic surface wave input transducer and an acoustic surface wave to electromagnetic wave output transducer and constituting a discrete acoustic surface wave filter, a pulsed source of electromagnetic wave energy connected to supply, simultaneously, electromagnetic wave pulses to each filter input transducer, a system clock connected to said source of electromagnetic wave energy, a switching matrix having an output and multiple inputs, each said filter output transducer being connected to a separate switch matrix input, and a switching matrix control means, said control means being connected to said switching matrix and to said system clock.
Claim 4
Dependent Claim
136 words
An acoustic surface wave frequency synthesizer comprising a single piezoelectric substrate member having an acoustic surface wave propagating surface, said propagating surface being divided into multiple parallel contiguous acoustic surface wave transmission channels, each transmission channel having an electromagnetic wave to acoustic surface wave input transducer and an acoustic surface wave to electromagnetic wave output transducer and constituting a discrete acoustic surface wave filter, a pulsed source of electromagnetic wave energy connected to supply, simultaneously, electromagnetic wave pulses to each filter input transducer, a system clock connected to said source of electromagnetic wave energy, a switching matrix having an output and multiple inputs, each said filter output transducer being connected to a separate switch matrix input, and a switching matrix control means, said control means being connected to said switching matrix and to said system clock.
Claim 5
Dependent Claim
39 words
An acoustic surface wave frequency synthesizer as defined in claim 2 wherein each filter has a discrete and different filter pass frequency, the combination of said filter pass frequencies defining, in substantially equal frequency increments, a given frequency band.
Claim 6
Dependent Claim
23 words
An acoustic surface wave frequency synthesizer as defined in claim 3 wherein said input and output transducers comprise thinned multiple finger interdigital electrodes.
Claim 7
Dependent Claim
21 words
An acoustic surface wave frequency synthesizer as defined in claim 4 wherein the interdigital fingers of said output transducer are apodized.
Claim 8
Dependent Claim
28 words
An acoustic surface wave frequency synthesizer as defined in claim 5 wherein the interdigital fingers of said output transducer are apodized in accordance with a cos2 apodization function.
Claim 9
Dependent Claim
22 words
An acoustic surface wave frequency synthesizer as defined in claim 6 wherein said piezoelectric substrate member consists of YZ cut lithium tantalate.
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) | 1978-06-23 | 1978-12-23 | 1979-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-23 | 1982-12-23 | 1983-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-23 | 1986-12-23 | 1987-06-24 | $7700.00 | Window Closed / Lapsed |