US3887770A
Expired / Lapsed
US
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Decoder apparatus adapted for different 4-channel matrix systems
Assignee: Sansui Electric Co Ltd
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Filing: 1973-11-28
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Granted: 1975-06-03
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Expires: 1993-11-28
Abstract
Abstract A decoder apparatus adapted for different four-channel matrix systems, wherein the sum and difference signals of two-channel composite signals are obtained by addition and subtraction respectively; an amplitude level ratio between the sum and difference signals is varied before addition and subtraction to obtain four-channel reproduced signals adapted for any of the different four-channel matrix systems. Where reproduction is to be effected according to one of the matrix systems, a sum signal and a difference signal used to reproduce rear signals are displaced 90* in phase by a phase shifter.
Inventors
- 👤 Susumu Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:04
CPC Classifications
H; H04; H04H; H04H20/00; H04H20/86; H04H20/88; H04H20/89; H04S; H04S3/00; H04S3/02
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
388 words
A decoder apparatus for decoding two-channel composite signals obtained by different four-channel matrix systems into four-channel signals in the form well matching any of said matrix systems comprising: first means connected to receive the two-channel composite signals for producing a sum signal; second means connected to receive the two-channel composite signals for producing a difference signal; third means connected to receive the sum and difference signals for additively combining the sum and difference signals to produce a first reproduced signal associated with one of front channels; fourth means connected to receive the sum and difference signals for subtractively combining the sum and difference signals to produce a second reproduced signal associated with the other of the front channels; fifth means for selectively varying an amplitude level ratio between the sum and difference signals supplied to said third and fourth means in accordance with the type of the two-channel composite signals being decoded; sixth means connected to receive the two-channel composite signals for generating a difference signal; seventh means connected to receive the two-channel composite signals for generating a sum signal; eighth means connected to receive the difference signal from said sixth means and the sum signal fRom said seventh means for additively combining the sum and difference signals to obtain a third reproduced signal associated with one of rear channels; ninth means connected to receive the difference signal from said sixth means and the sum signal from said seventh means for subtractively combining the sum and difference signals to obtain a fourth reproduced signal associated with the other of the rear channels; tenth means for varying an amplitude level ratio between the sum and difference signals supplied to said eighth and ninth means simultaneously with the ratio varying operation of said fifth means; and at least one first phase shifting means selectively connected in circuit or out of circuit with respect to the inputs to said eighth and ninth means simultaneously with the ratio varying operation of said fifth and tenth means such that when said first phase shifting means is in circuit one input to said eighth and ninth means is phase shifted with respect to the other input thereto and when said first phase shifting means is out of circuit it produces no relative phase shift of the input signals to said eighth and ninth means.
Claim 2
Dependent Claim
388 words
A decoder apparatus for decoding two-channel composite signals obtained by different four-channel matrix systems into four-channel signals in the form well matching any of said matrix systems comprising: first means connected to receive the two-channel composite signals for producing a sum signal; second means connected to receive the two-channel composite signals for producing a difference signal; third means connected to receive the sum and difference signals for additively combining the sum and difference signals to produce a first reproduced signal associated with one of front channels; fourth means connected to receive the sum and difference signals for subtractively combining the sum and difference signals to produce a second reproduced signal associated with the other of the front channels; fifth means for selectively varying an amplitude level ratio between the sum and difference signals supplied to said third and fourth means in accordance with the type of the two-channel composite signals being decoded; sixth means connected to receive the two-channel composite signals for generating a difference signal; seventh means connected to receive the two-channel composite signals for generating a sum signal; eighth means connected to receive the difference signal from said sixth means and the sum signal fRom said seventh means for additively combining the sum and difference signals to obtain a third reproduced signal associated with one of rear channels; ninth means connected to receive the difference signal from said sixth means and the sum signal from said seventh means for subtractively combining the sum and difference signals to obtain a fourth reproduced signal associated with the other of the rear channels; tenth means for varying an amplitude level ratio between the sum and difference signals supplied to said eighth and ninth means simultaneously with the ratio varying operation of said fifth means; and at least one first phase shifting means selectively connected in circuit or out of circuit with respect to the inputs to said eighth and ninth means simultaneously with the ratio varying operation of said fifth and tenth means such that when said first phase shifting means is in circuit one input to said eighth and ninth means is phase shifted with respect to the other input thereto and when said first phase shifting means is out of circuit it produces no relative phase shift of the input signals to said eighth and ninth means.
Claim 3
Dependent Claim
388 words
A decoder apparatus for decoding two-channel composite signals obtained by different four-channel matrix systems into four-channel signals in the form well matching any of said matrix systems comprising: first means connected to receive the two-channel composite signals for producing a sum signal; second means connected to receive the two-channel composite signals for producing a difference signal; third means connected to receive the sum and difference signals for additively combining the sum and difference signals to produce a first reproduced signal associated with one of front channels; fourth means connected to receive the sum and difference signals for subtractively combining the sum and difference signals to produce a second reproduced signal associated with the other of the front channels; fifth means for selectively varying an amplitude level ratio between the sum and difference signals supplied to said third and fourth means in accordance with the type of the two-channel composite signals being decoded; sixth means connected to receive the two-channel composite signals for generating a difference signal; seventh means connected to receive the two-channel composite signals for generating a sum signal; eighth means connected to receive the difference signal from said sixth means and the sum signal fRom said seventh means for additively combining the sum and difference signals to obtain a third reproduced signal associated with one of rear channels; ninth means connected to receive the difference signal from said sixth means and the sum signal from said seventh means for subtractively combining the sum and difference signals to obtain a fourth reproduced signal associated with the other of the rear channels; tenth means for varying an amplitude level ratio between the sum and difference signals supplied to said eighth and ninth means simultaneously with the ratio varying operation of said fifth means; and at least one first phase shifting means selectively connected in circuit or out of circuit with respect to the inputs to said eighth and ninth means simultaneously with the ratio varying operation of said fifth and tenth means such that when said first phase shifting means is in circuit one input to said eighth and ninth means is phase shifted with respect to the other input thereto and when said first phase shifting means is out of circuit it produces no relative phase shift of the input signals to said eighth and ninth means.
Claim 4
Dependent Claim
388 words
A decoder apparatus for decoding two-channel composite signals obtained by different four-channel matrix systems into four-channel signals in the form well matching any of said matrix systems comprising: first means connected to receive the two-channel composite signals for producing a sum signal; second means connected to receive the two-channel composite signals for producing a difference signal; third means connected to receive the sum and difference signals for additively combining the sum and difference signals to produce a first reproduced signal associated with one of front channels; fourth means connected to receive the sum and difference signals for subtractively combining the sum and difference signals to produce a second reproduced signal associated with the other of the front channels; fifth means for selectively varying an amplitude level ratio between the sum and difference signals supplied to said third and fourth means in accordance with the type of the two-channel composite signals being decoded; sixth means connected to receive the two-channel composite signals for generating a difference signal; seventh means connected to receive the two-channel composite signals for generating a sum signal; eighth means connected to receive the difference signal from said sixth means and the sum signal fRom said seventh means for additively combining the sum and difference signals to obtain a third reproduced signal associated with one of rear channels; ninth means connected to receive the difference signal from said sixth means and the sum signal from said seventh means for subtractively combining the sum and difference signals to obtain a fourth reproduced signal associated with the other of the rear channels; tenth means for varying an amplitude level ratio between the sum and difference signals supplied to said eighth and ninth means simultaneously with the ratio varying operation of said fifth means; and at least one first phase shifting means selectively connected in circuit or out of circuit with respect to the inputs to said eighth and ninth means simultaneously with the ratio varying operation of said fifth and tenth means such that when said first phase shifting means is in circuit one input to said eighth and ninth means is phase shifted with respect to the other input thereto and when said first phase shifting means is out of circuit it produces no relative phase shift of the input signals to said eighth and ninth means.
Claim 5
Dependent Claim
19 words
A decoder apparatus according to claim 1 wherein said fifth and tenth means respectively include a voltage dividing circuit.
Claim 6
Dependent Claim
19 words
A decoder apparatus according to claim 1 wherein said fifth and tenth means respectively include a variable gain amplifier.
Claim 7
Dependent Claim
31 words
A decoder apparatus according to claim 1 wherein said first phase shifting means is operative to introduce between the sum and difference signals a predetermined relative phase difference of substantially 90*.
Claim 8
Dependent Claim
140 words
A decoder apparatus according to claim 1 further comprising second and third phase shifting means connected to input sides of said first, second, sixth and seventh means for shifting the phases of the two-channel composite signals by a reference phase-shift angle; eleventh means connected to receive two-channel signals whose phases are not shifted for generating a sum signal; and means interlockingly actuated with the ratio varying operations of said fifth and tenth means for supplying said eighth and ninth means with the sum signal from said eleventh means in place of the sum signal from said seventh means, and wherein said first phase shifting means is operative to introduce between the difference signal from said sixth means and the sum signal from said eleventh means a relative phase difference which is different from the reference phase-shift angle by substantially 90*.
Claim 9
Dependent Claim
42 words
A decoder apparatus according to claim 1 further comprising: second phase shifting means with the output of said eighth means connected as the input thereto; and third phase shifting means with the output of said ninth means connected as the input thereto.
Claim 10
Dependent Claim
242 words
A decoder apparatus for decoding two-channel composite signals obtained by different four-channel matrix systems into four-channel output signals comprising: first means for additively combining sum and difference signals of the composite signals to produce a first output; second means for subtractively combining sum and difference signals of the composite signals to produce a second output; first gain control amplifier means connected to receive the difference signal of the composite signals which is applied to said first and second means; third means for additively combining sum and difference signals of the composite signals to produce a third output; fourth means for subtractively combining sum and difference signals of the composite signals to produce a fourth output; second gain control amplifier means connected to receive the sum signal of the composite signals which is applied to said third and fourth means; changing means for changing the gains of said first and second gain control amplifier in accordance with the type of the composite signals being decoded; and phase shifting means selectively connected in circuit or out of circuit with tHe inputs of said third and fourth means in association with operation of said changing means, said phase shifting means being operative to introduce a relative phase shift of substantially 90* between the sum and difference signals of the composite signals which are applied to said third and fourth means only when said phase shifting means is in circuit with said third and fourth means.
Claim 11
Dependent Claim
242 words
A decoder apparatus for decoding two-channel composite signals obtained by different four-channel matrix systems into four-channel output signals comprising: first means for additively combining sum and difference signals of the composite signals to produce a first output; second means for subtractively combining sum and difference signals of the composite signals to produce a second output; first gain control amplifier means connected to receive the difference signal of the composite signals which is applied to said first and second means; third means for additively combining sum and difference signals of the composite signals to produce a third output; fourth means for subtractively combining sum and difference signals of the composite signals to produce a fourth output; second gain control amplifier means connected to receive the sum signal of the composite signals which is applied to said third and fourth means; changing means for changing the gains of said first and second gain control amplifier in accordance with the type of the composite signals being decoded; and phase shifting means selectively connected in circuit or out of circuit with tHe inputs of said third and fourth means in association with operation of said changing means, said phase shifting means being operative to introduce a relative phase shift of substantially 90* between the sum and difference signals of the composite signals which are applied to said third and fourth means only when said phase shifting means is in circuit with said third and fourth means.
References Cited (Backward Citations)
US3783192A
Cited
US3787192A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |