US4935814A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Picture quality indicator for satellite broadcasting receiver
Assignee: Panasonic Holdings Corp
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Filing: 1988-12-28
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Granted: 1990-06-19
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Expires: 2008-12-28
Abstract
Abstract By the extraction of the noise component from the FM demodulated output and the detection thereof, the output proportional to the noise power is obtained, and it is indicated as the CN ratio of the received signal. This quality indication of the received signal makes the antenna pointing angle adjustment easier than before, and also realizes the picture quality indication for a satellite broadcasting receiver.
Inventors
- 👤 Noriaki Omoto
- 👤 Mitsugu Kuboki
- 👤 Osamu Shizuya
- 👤 Yoshikazu Yoshimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:14
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/44; H04N5/445; H04N17/00; H01; H01Q; H01Q1/00; H01Q1/12; H01Q1/125; H01Q1/1257; H04N7/00; H04N7/20
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
89 words
Picture quality indicator for satellite broadcasting receiver comprising: an FM-demodulator for demodulating the satellite broadcasting signal, a band-pass filter for extracting a noise component from the output signal of said FM demodulator thereby removing TV signal components, an amplifier for amplifying said noise component, a detection circuit for detecting and outputting the amount of the noise component output from said amplifier, and a level indicator for indicating a value corresponding to a CN ratio of the TV signal obtained on the basis of the output of said detection circuit.
Claim 2
Dependent Claim
89 words
Picture quality indicator for satellite broadcasting receiver comprising: an FM-demodulator for demodulating the satellite broadcasting signal, a band-pass filter for extracting a noise component from the output signal of said FM demodulator thereby removing TV signal components, an amplifier for amplifying said noise component, a detection circuit for detecting and outputting the amount of the noise component output from said amplifier, and a level indicator for indicating a value corresponding to a CN ratio of the TV signal obtained on the basis of the output of said detection circuit.
Claim 3
Dependent Claim
46 words
Picture quality indicator for satellite broadcasting receiver in accordance with claim 1, wherein the band-pass filter passes only the noise component which includes no video luminance signal component, no color sub-carrier nor its second, third harmonic components, and no audio sub-carrier component nor its harmonic components.
Claim 4
Dependent Claim
33 words
Picture quality indicator for satellite broadcasting receiver stated in claim 1, wherein the amplifier amplifying the noise component is an amplitude-limiting type amplifier wherein the amplification gain decreases as the noise level increases.
Claim 5
Dependent Claim
121 words
Picture quality indicator for satellite broadcasting receiver comprising: an FM-demodulator for demodulating the satellite broadcasting signal, a band-pass filter for extracting a noise component from the output signal of said FM demodulator thereby removing TV signal components, a first amplifier for amplifying said noise component, a detection circuit for detecting and outputting the amount of the noise component output from said first amplifier, a second amplifier for amplifying the output of said detection circuit, said second amplifier having a variable gain characteristic such that the gain thereof decreases as the input thereto increases, and a level indicator for indicating a value corresponding to a CN ratio of the TV signal obtained on the basis of the output of said detection circuit.
Claim 6
Dependent Claim
121 words
Picture quality indicator for satellite broadcasting receiver comprising: an FM-demodulator for demodulating the satellite broadcasting signal, a band-pass filter for extracting a noise component from the output signal of said FM demodulator thereby removing TV signal components, a first amplifier for amplifying said noise component, a detection circuit for detecting and outputting the amount of the noise component output from said first amplifier, a second amplifier for amplifying the output of said detection circuit, said second amplifier having a variable gain characteristic such that the gain thereof decreases as the input thereto increases, and a level indicator for indicating a value corresponding to a CN ratio of the TV signal obtained on the basis of the output of said detection circuit.
References Cited (Backward Citations)
US4125809A
Cited
US4214273A
Cited
US4281348A
Cited
US4349840A
Cited
DE3121611A1
Cited
EP0117598A1
Cited
US4605968A
Cited
US4658438A
Cited
DE3513361A1
Cited
US4723303A
Cited
US4721997A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-06-18 | 1993-12-18 | 1994-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-18 | 1997-12-18 | 1998-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-18 | 2001-12-18 | 2002-06-19 | $7700.00 | Window Closed / Lapsed |