US3657655A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detection system for control information
Assignee: Individual
•
Filing: 1969-04-15
•
Granted: 1972-04-18
•
Expires: 1989-04-15
Abstract
Abstract Disclosed herein is a detection system for control information transmitted from the sending side to the receiving side in a broadcast system, in which the control information is detected in consideration of the following two conditions: (1) if a control signal representative of the control information is intermitted by the control at the sending side or by noise, the control signal is deemed continuous in case of the intermitted time of the control signal is less than a predetermined first time (t); and (2) if a signal deemed continuous exceeds a predetermined second time (T) longer than the first time (t), this signal is decided as the control information.
Inventors
- 👤 Masayuki Fukata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:58
CPC Classifications
H; H04; H04H; H04H20/00; H04H20/28
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
154 words
A system for detecting control information transmitted in a transmission path of a broadcast system, comprising: selection means coupled with the transmission path for selecting at least one frequency representative of the control information, rectifying means connected to the output of said selection means for rectifying the output signal of the selection means so as to produce pulses of periods equal to the periods of respective continuous signals from the output of said selection means, a pulse-width expander connected to the rectifying means for expanding, by a first time (t), the duration of each of said pulses so as to produce a continuous DC voltage when the intermitted periods in the control information signals are less than said first time (t), and decision means connected to the output of the pulse-width expander for deciding when the duration of the continuous DC voltage exceeds a predetermined second time (T) and for producing an indication thereof.
Claim 2
Independent Claim
154 words
A system for detecting control information transmitted in a transmission path of a broadcast system, comprising: selection means coupled with the transmission path for selecting at least one frequency representative of the control information, rectifying means connected to the output of said selection means for rectifying the output signal of the selection means so as to produce pulses of periods equal to the periods of respective continuous signals from the output of said selection means, a pulse-width expander connected to the rectifying means for expanding, by a first time (t), the duration of each of said pulses so as to produce a continuous DC voltage when the intermitted periods in the control information signals are less than said first time (t), and decision means connected to the output of the pulse-width expander for deciding when the duration of the continuous DC voltage exceeds a predetermined second time (T) and for producing an indication thereof.
Claim 3
Dependent Claim
48 words
A detection system of control information according to claim 1, in which the decision means comprises a timer performing the time measurement by the output of the pulse width expander and restoring the measurement result thereof by the inverse signal of the output of the pulse width expander.
Claim 4
Dependent Claim
48 words
A detection system of control information according to claim 1, in which the decision means comprises a timer performing the time measurement by the output rectified of the selection means and restoring the measurement result thereof by the inverse signal of the output of the pulse width expander.
Claim 5
Dependent Claim
77 words
A detection system of control information according to claim 1, in which the decision means comprises a bistable circuit set by the output rectified of the selection means and reset by the inverse signal of the output of the pulse width expander, and a timer performing the time measurement in a case of the set state of the bistable circuit and restoring the measurement result thereof in a case of the reset state of the bistable circuit.
Claim 6
Dependent Claim
48 words
A detection system of control information according to claim 1, in which a plurality of selectiOn means is provided for selecting a plurality of tones representative of the control information, and a logical product of the outputs of the selection means is applied to the pulse width expander.
References Cited (Backward Citations)
US3496467A
Cited
US3513399A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-18 | 1975-10-18 | 1976-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-18 | 1979-10-18 | 1980-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-18 | 1983-10-18 | 1984-04-18 | $7700.00 | Window Closed / Lapsed |