US3602737A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit arrangement for reduction of high frequency noise disturbances in wide bandsignals such as video signals
Assignee: Robert Bosch Fernsehanlagen GmbH
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Filing: 1970-02-18
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Granted: 1971-08-31
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Expires: 1990-02-18
Abstract
Abstract System for reducing noise in video signals by subtracting coherent noise modulation from useful signal. The high frequency component of the video signal is separated into parts above and below a given amplitude. The low-amplitude part corresponds to the noise level and is subtracted from the wide-band signal. The high-amplitude part is restored for compensation.
Inventors
- 👤 Helmut Radecke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:02
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/14; H04N5/21; H03; H03G; H03G5/00; H03G5/16; H03G5/18; H03G9/00; H03G9/02; H03G9/025
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
110 words
A circuit arrangement for reduction of high-frequency noise disturbances in a wide-band electrical signal comprising: a. amplitude-division means responsive to the higher-frequency components of said wide-band signal for dividing said components into a low-amplitude signal having signal amplitudes below a predetermined value and a high-amplitude signal having signal amplitudes above said predetermined value, b. means for subtracting said low-amplitude signal from said wide-band signal to form a difference signal, and c. means for adding said high amplitude signal to said difference signal to derive an output signal, whereby the transmission characteristic for the higher-frequency signals having low amplitude is smaller than it is for the highfrequency signals having high amplitude.
Claim 2
Dependent Claim
110 words
A circuit arrangement for reduction of high-frequency noise disturbances in a wide-band electrical signal comprising: a. amplitude-division means responsive to the higher-frequency components of said wide-band signal for dividing said components into a low-amplitude signal having signal amplitudes below a predetermined value and a high-amplitude signal having signal amplitudes above said predetermined value, b. means for subtracting said low-amplitude signal from said wide-band signal to form a difference signal, and c. means for adding said high amplitude signal to said difference signal to derive an output signal, whereby the transmission characteristic for the higher-frequency signals having low amplitude is smaller than it is for the highfrequency signals having high amplitude.
Claim 3
Dependent Claim
51 words
A circuit arrangement according to claim 1 wherein said wide-band electrical signals are television signals, said predetermined value corresponds to a typical maximum value of the noise disturbance, and further comprising means for equalizing the transit time and level of said low-amplitude signal before using it in said means for subtracting.
Claim 4
Dependent Claim
115 words
A circuit arrangement according to claim 1 wherein said amplitude-division means further comprises a. two transistors of opposite conductivity type, each having emitter, collector and base, b. means for delivering said higher frequency components to the emitters of said two transistors with different DC mean values corresponding to said predetermined value being associated with the two emitter signals, c. means for bringing the bases of the two transistors to a common mean potential between the DC mean values, d. means for taking the signal components lying below the predetermined value from the emitters of the transistors, and e. means for taking the signal components lying above the predetermined value from the collectors of the transistors.
Claim 5
Dependent Claim
39 words
A circuit arrangement according to claim 3, wherein said two transistors are of a type typified by silicon transistors which have a sufficiently high-forward voltage that the fixing of the predetermined value can be effected with only three resistances.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-30 | 1975-03-01 | 1975-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-30 | 1979-03-01 | 1979-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-30 | 1983-03-01 | 1983-08-31 | $7700.00 | Window Closed / Lapsed |