Patent US3721753A successfully refreshed from Google Patents.
US3721753A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Color television receiver
Assignee: Sony Corp
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Filing: 1971-10-22
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Granted: 1973-03-20
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Expires: 1991-10-22
Abstract
Abstract A decoding system to receive PAL color television signals in which one line of chrominance information is applied to synchronous demodulators and the same line, delayed one line interval by means of a switching circuit and delay means, is again applied to the same demodulators. Detecting means are provided for detecting the phase of burst signals in the chrominance information applied to the demodulators. Reference subcarrier generating means connected to the demodulators are phase-controlled in response to the phase of the burst signals, and the switching circuit is controlled by the output of the detecting means in response to the phase of the burst signal so as to apply to the demodulators only the chrominance information whose suppressed carrier signal has a predetermined phase relation with the reference subcarriers.
Inventors
- 👤 K Mima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:14
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/44; H04N9/465
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
170 words
A decoding system for chrominance signal components of a color television signal transmitted in accordance with a phase alternation by line system, said decoding system comprising: A. First circuit means comprising: 1. delay means for delaYing said chrominance signal components for substantially one line period, and 2. switch means operative to change the condition thereof at every line period, said circuit means producing first and second sets of modified chrominance signals, each of said sets being composed of the delayed and non-delayed chrominance signal components arranged in sequence alternately every line period; B. First and second demodulator means for demodulating at least one of said sets of modified chrominance signals; C. Means for extracting burst signals from said first and second sets of modified chrominance signals, respectively; D. Second circuit means supplied with said burst signals to produce a control signal in response to the phase of said burst signals; and E. Controlling means for controlling said switch means in said first circuit means in accordance with said control signal.
Claim 2
Dependent Claim
170 words
A decoding system for chrominance signal components of a color television signal transmitted in accordance with a phase alternation by line system, said decoding system comprising: A. First circuit means comprising: 1. delay means for delaYing said chrominance signal components for substantially one line period, and 2. switch means operative to change the condition thereof at every line period, said circuit means producing first and second sets of modified chrominance signals, each of said sets being composed of the delayed and non-delayed chrominance signal components arranged in sequence alternately every line period; B. First and second demodulator means for demodulating at least one of said sets of modified chrominance signals; C. Means for extracting burst signals from said first and second sets of modified chrominance signals, respectively; D. Second circuit means supplied with said burst signals to produce a control signal in response to the phase of said burst signals; and E. Controlling means for controlling said switch means in said first circuit means in accordance with said control signal.
Claim 3
Dependent Claim
67 words
A decoding system according to claim 1 in which said switch means comprises: A. A switching circuit changed over at every line period so that the sequence of said delayed and non-delayed chrominance signal components in said first set of modified chrominance signals is reversed with respect to the sequence in said second set of modified chrominance signals; and B. An actuating circuit operating said switching circuit.
Claim 4
Dependent Claim
123 words
switch means operative to change the condition thereof at every line period, said circuit means producing first and second sets of modified chrominance signals, each of said sets being composed of the delayed and non-delayed chrominance signal components arranged in sequence alternately every line period; B. First and second demodulator means for demodulating at least one of said sets of modified chrominance signals; C. Means for extracting burst signals from said first and second sets of modified chrominance signals, respectively; D. Second circuit means supplied with said burst signals to produce a control signal in response to the phase of said burst signals; and E. Controlling means for controlling said switch means in said first circuit means in accordance with said control signal.
Claim 5
Dependent Claim
123 words
switch means operative to change the condition thereof at every line period, said circuit means producing first and second sets of modified chrominance signals, each of said sets being composed of the delayed and non-delayed chrominance signal components arranged in sequence alternately every line period; B. First and second demodulator means for demodulating at least one of said sets of modified chrominance signals; C. Means for extracting burst signals from said first and second sets of modified chrominance signals, respectively; D. Second circuit means supplied with said burst signals to produce a control signal in response to the phase of said burst signals; and E. Controlling means for controlling said switch means in said first circuit means in accordance with said control signal.
Claim 6
Dependent Claim
47 words
A decoding system according to claim 2 in which said switching circuit comprises: A. At least two input terminals supplied with the delayed and non-delayed chrominance signal components, respectively; and B. At least two output terminals deriving said first and second sets of modified chrominance signals, respectively.
Claim 7
Dependent Claim
27 words
A decoding system according to claim 2 in which said actuating circuit is connected to said controlling means to be controlled in accordance with said control signal.
Claim 8
Dependent Claim
21 words
A decoding system according to claim 4 in which said actuating circuit comprises a flip-flop circuit connected to said switching circuit.
Claim 9
Dependent Claim
90 words
A decoding system according to claim 5 in which said phase-comparing circuit comprises: A. A local oscillator connected to said means for extracting burst signals to be controlled in response to one of said burst signals; B. A phase shifter for phase-shifting the output from said local oscillator relative to the other of said burst signals by a predetermined phase angle; and C. A phase detector connected to said phase shifter for detecting the phase relationship between said other of the burst signals and the output from said local oscillator.
Claim 10
Dependent Claim
91 words
A decoding system according to claim 5 in which said phase-comparing circuit comprises: A. A local oscillator connected to said means for extracting burst signals to be controlled in response to one of said burst signals; B. A phase shifter connected to said oscillator for phase-shifting the output therefrom relative to the other of said burst signals by a predetermined phase angle; and C. A phase detector connected to said phase shifter for detecting the phase relationship between said other of the burst signals and the output from said local oscillator.
Claim 11
Dependent Claim
46 words
A decoding system according to claim 1 in which said second circuit means has a phase-comparing circuit comparing the phases of the burst signals extracted from said first and second sets of modified chrominance signals, said phase-comparing circuit producing said control signal as an output signal.
Claim 12
Dependent Claim
27 words
A decoding system according to claim 8 in which means is provided for supplying the output of said local oscillator to said first and second demodulator means.
Claim 13
Dependent Claim
71 words
A decoding system according to claim 1 in which said second circuit means comprises: A. A phase shifter for phase-shifting at least one of the burst signals extracted from said first and second modified chrominance signals by a predetermined phase angle; and B. An adding circuit for adding said burst signals, at least one of which is phase-shifted, and the output of sAid adding circuit is formed into said control signal.
Claim 14
Dependent Claim
46 words
A decoding circuit according to claim 10 in which said second circuit further comprises: A. A local oscillator controlled in response to the output of said adding circuit; and B. Means for supplying the output of said local oscillator to said first and second demodulator means.
Claim 15
Dependent Claim
29 words
A decoding system according to claim 11 in which said second circuit further comprises means for making continuous wave signals from said burst signals respectively before said adding circuit.
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) | 1976-03-19 | 1976-09-18 | 1977-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-19 | 1980-09-18 | 1981-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-19 | 1984-09-18 | 1985-03-20 | $7700.00 | Window Closed / Lapsed |