US5021882A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Definition television systems
Assignee: Massachusetts Institute of Technology
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Filing: 1989-05-24
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Granted: 1991-06-04
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Expires: 2009-05-24
Abstract
Abstract A receiver-compatible EDTV system wherein enhancement information is adaptively modulated to suppress channel noise and is transmitted outside the usable picture area of a receiver compatible signal of the receiver compatible EDTV system.
Inventors
- 👤 William F. Schreiber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 03:49
CPC Classifications
H; H04; H04N; H04N19/00; H04N19/10; H04N19/169; H04N19/186; H04N11/00; H04N11/24; H04N11/28; H04N19/60; H04N19/61; H04N19/619; H04N19/63; H04N7/00; H04N7/04; H04N7/08
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
67 words
A receiver-compatible EDTV system comprising means for adaptively modulating an enhancement signal so as to suppress channel noise and means for transmitting the adaptively-modulated enhancement signal as part of a receiver-compatible signal and outside the usable picture area of the receiver-compatible EDTV system but within at least a portion of the usable picture area of an NTSC system, said receiver-compatible signal carrying an EDTV aspect ratio image.
Claim 2
Dependent Claim
67 words
A receiver-compatible EDTV system comprising means for adaptively modulating an enhancement signal so as to suppress channel noise and means for transmitting the adaptively-modulated enhancement signal as part of a receiver-compatible signal and outside the usable picture area of the receiver-compatible EDTV system but within at least a portion of the usable picture area of an NTSC system, said receiver-compatible signal carrying an EDTV aspect ratio image.
Claim 3
Dependent Claim
41 words
The system of claim 1 further comprising means for increasing effective bandwidth at the expense of signal-to-noise ratio by superimposing a reduced amplitude enhancement signal on a multilevel digital signal, said reduced-amplitude enhancement signal being derived from the adaptively-modulated enhancement signal.
Claim 4
Dependent Claim
57 words
The system of claim 1 further comprising a receiver compatible with said enhanced-definition television system, said receiver comprising compatible front-end circuitry for selecting and demodulating the received RF signal to produce a video signal, compatible processing circuitry for processing the video signal to produce display data, and display circuitry to display said data on a display device.
Claim 5
Dependent Claim
29 words
The system of claim 1 wherein the enhancement signal is placed within bar areas located at the top and/or bottom of the usable picture area of the NTSC system.
Claim 6
Dependent Claim
38 words
The system of claim 1 wherein said high frequency information lies outside a block of frequency space, said block having the dimensions of about 425 samples per width by 240 lines per height by 12 frames per second.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-06-03 | 1994-12-03 | 1995-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-03 | 1998-12-03 | 1999-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-03 | 2002-12-03 | 2003-06-04 | $7700.00 | Window Closed / Lapsed |