US5027210A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Noise reduction in high definition television signals
Assignee: National Transcommunications Ltd
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Filing: 1988-03-30
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Granted: 1991-06-25
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Expires: 2008-03-30
Abstract
Abstract In a high definition multiplexed analog component system, a high definition signal is processed by splitting it into high and low frequency components and pre-emphasizing the high frequency component with a non-linear characteristic and at the receiver a complementary de-emphasis process is applied to produce a noise-reduced high definition signal compatible with existing conventional receivers. A processor of a pre-connector for the high definition signal can be used for intersample interference due to non-compatibility between the pre and de-emphasis characteristics in a digital implementation of the system.
Inventors
- 👤 Brian H. Beech
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:17
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/14; H04N5/21; H04N11/00; H04N11/24
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
121 words
A method of processing a high definition television signal, comprising the steps of: filtering the signal to provide a high frequency sub-band and a low frequency sub-band; applying a non-linear pre-emphasis signal to the high frequency sub-band; recombining and transmitting the signal; receiving the signal; filtering the received signal to provide high frequency and low frequency sub-bands; applying a complementary non-linear de-emphasis to the high frequency sub-band; and wherein the processing is carried out by analoq circuitry means; the steps of filtering the signal and applying pre-emphasis are carried out by the single step of applying the signal to a feedback loop, the feedback loop including a characteristic corresponding to the filtering and de-emphasis to be applied to the received signal.
Claim 2
Independent Claim
121 words
A method of processing a high definition television signal, comprising the steps of: filtering the signal to provide a high frequency sub-band and a low frequency sub-band; applying a non-linear pre-emphasis signal to the high frequency sub-band; recombining and transmitting the signal; receiving the signal; filtering the received signal to provide high frequency and low frequency sub-bands; applying a complementary non-linear de-emphasis to the high frequency sub-band; and wherein the processing is carried out by analoq circuitry means; the steps of filtering the signal and applying pre-emphasis are carried out by the single step of applying the signal to a feedback loop, the feedback loop including a characteristic corresponding to the filtering and de-emphasis to be applied to the received signal.
Claim 3
Dependent Claim
23 words
A method in accordance with claim 1 and including the further step of filtering the de-emphasized signal to attenuate out of band components.
Claim 4
Independent Claim
26 words
A method of processing in accordance with claims 1 and wherein the non-linear characteristic is arranged such that its effect is symmetric independent of static deviation.
Claim 5
Dependent Claim
53 words
A method of processing in accordance with claim 1 and wherein the non-linear pre-emphasis is of the form: VO=Ve.sup.(q/KTM) (Vi-VO) -Ve.sup.-(q/KTM) (Vi-VO) (where Vi is the input voltage; VO is the output voltage; q is the electron charge; K is Boltzman's constant T is absolute temperature; and V and M are shape factors).
Claim 6
Dependent Claim
53 words
A method of processing in accordance with claim 2 and wherein the non-linear pre-emphasis is of the form: VO=Ve.sup.(q/KTM) (Vi-VO) -Ve.sup.-(q/KTM) (Vi-VO) (where Vi is the input voltage; VO is the output voltage; q is the electron charge; K is Boltzman's constant T is absolute temperature; and V and M are shape factors).
Claim 7
Dependent Claim
53 words
A method of processing in accordance with claim 3 and wherein the non-linear pre-emphasis is of the form: VO=Ve.sup.(q/KTM) (Vi-VO) -Ve.sup.-(q/KTM) (Vi-VO) (where Vi is the input voltage; VO is the output voltage; q is the electron charge; K is Boltzman's constant T is absolute temperature; and V and M are shape factors).
Claim 8
Dependent Claim
26 words
A method of processing in accordance with claim 2 and wherein the non-linear characteristic is arranged such that its effect is symmetric independent of static deviation.
Claim 9
Dependent Claim
53 words
A method of processing in accordance with claim 7 and wherein the non-linear pre-emphasis is of the form: VO=Ve.sup.(q/KTM) (Vi-VO) -Ve.sup.-(q/KTM) (Vi-VO) (where Vi is the input voltage; VO is the output voltage; q is the electron charge; K is Boltzman's constant T is absolute temperature; and V and M are shape factors).
Claim 10
Independent Claim
103 words
A method of processing a high definition television signal, comprising the steps of: filtering the signal to provide a high frequency sub-band and a low frequency sub-band; applying a non-linear pre-emphasis signal to the high frequency sub-band; recombining and transmitting the signal; receiving the signal; filtering the received signal to provide high frequency and low frequency sub-bands; applying a complementary non-linear de-emphasis to the high frequency sub-band; and wherein the processing is carried out by digital circuitry means; and further comprising the step applying pre-correction prior to filtering and pre-emphasis to compensate for errors due to the pre and de-emphasis characteristics being non-complementary.
Claim 11
Independent Claim
103 words
A method of processing a high definition television signal, comprising the steps of: filtering the signal to provide a high frequency sub-band and a low frequency sub-band; applying a non-linear pre-emphasis signal to the high frequency sub-band; recombining and transmitting the signal; receiving the signal; filtering the received signal to provide high frequency and low frequency sub-bands; applying a complementary non-linear de-emphasis to the high frequency sub-band; and wherein the processing is carried out by digital circuitry means; and further comprising the step applying pre-correction prior to filtering and pre-emphasis to compensate for errors due to the pre and de-emphasis characteristics being non-complementary.
Claim 12
Dependent Claim
32 words
A method of processing in accordance with claim 9 and wherein the pre-correction applied is also designed to correct for intersample interference produced by the channel along which the signal is transmitted.
Claim 13
Dependent Claim
26 words
A method of processing in accordance with claim 9 and wherein the non-linear characteristic is arranged such that its effect is symmetric independent of static deviation.
Claim 14
Dependent Claim
53 words
A method of processing in accordance with claim 9 and wherein the non-linear pre-emphasis is of the form: VO=Ve.sup.(q/KTM) (Vi-VO) -Ve.sup.-(q/KTM) (Vi-VO) (where Vi is the input voltage; VO is the output voltage; q is the electron charge; K is Boltzman's constant T is absolute temperature; and V and M are shape factors).
Claim 15
Dependent Claim
53 words
A method of processing in accordance with claim 10 and wherein the non-linear pre-emphasis is of the form: VO=Ve.sup.(q/KTM) (Vi-VO) -Ve.sup.-(q/KTM) (Vi-VO) (where Vi is the input voltage; VO is the output voltage; q is the electron charge; K is Boltzman's constant T is absolute temperature; and V and M are shape factors).
Claim 16
Dependent Claim
53 words
A method of processing in accordance with claim 11 and wherein the non-linear pre-emphasis is of the form: VO=Ve.sup.(q/KTM) (Vi-VO) -Ve.sup.-(q/KTM) (Vi-VO) (where Vi is the input voltage; VO is the output voltage; q is the electron charge; K is Boltzman's constant T is absolute temperature; and V and M are shape factors).
Claim 17
Dependent Claim
26 words
A method of processing in accordance with claim 10 and wherein the non-linear characteristic is arranged such that its effect is symmetric independent of static deviation.
Claim 18
Dependent Claim
53 words
A method of processing in accordance with claim 15 and wherein the non-linear pre-emphasis is of the form: VO=Ve.sup.(q/KTM) (Vi-VO) -Ve.sup.-(q/KTM) (Vi-VO) (where Vi is the input voltage; VO is the output voltage; q is the electron charge; K is Boltzman's constant T is absolute temperature; and V and M are shape factors).
Claim 19
Dependent Claim
110 words
A transmitter circuit for a high definition television signal, the circuit comprising: filter means arranged to split the signal into high and low frequency sub-bands: means for applying a non-linear pre-emphasis to the signal, the non-linear pre-emphasis characteristic being arranged to be complementary to a non-linear de-emphasis characteristic to be applied at the receiver end; and wherein the circuit provides analog processing; and the filter means and means for applying non-linear pre-emphasis comprise a feedback loop into which the signal is input, the feedback loop including circuit means for filtering the feedback signal and applying a non-linear de-emphasis thereto, the non-linear de-emphasis being complementary to the pre-emphasis characteristic being applied.
Claim 20
Dependent Claim
110 words
A transmitter circuit for a high definition television signal, the circuit comprising: filter means arranged to split the signal into high and low frequency sub-bands: means for applying a non-linear pre-emphasis to the signal, the non-linear pre-emphasis characteristic being arranged to be complementary to a non-linear de-emphasis characteristic to be applied at the receiver end; and wherein the circuit provides analog processing; and the filter means and means for applying non-linear pre-emphasis comprise a feedback loop into which the signal is input, the feedback loop including circuit means for filtering the feedback signal and applying a non-linear de-emphasis thereto, the non-linear de-emphasis being complementary to the pre-emphasis characteristic being applied.
Claim 21
Dependent Claim
52 words
A transmitter circuit in accordance with claim 17 and wherein the non-linear pre-emphasis is of the form: VO=Ve.sup.(q/KTM) (Vi-VO) -Ve.sup.-(q/KTM) (Vi-VO) (where Vi is the input voltage; VO is the output voltage; q is the electron charge; K is Boltzman's constant T is absolute temperature; and V and M are shape factors).
Claim 22
Dependent Claim
83 words
A transmitter circuit for a high definition television signal, the circuit comprising: filter means arranged to split the signal into high and low frequency sub-bands: means for applying a non-linear pre-emphasis to the signal, the non-linear pre-emphasis characteristic being arranged to be complementary to a non-linear de-emphasis characteristic to be applied at the receiver end; and wherein the circuit provides digital processing; and further comprising: pre-corrector circuitry for applying a pre-correction function to the signal before filtering and pre-emphasis to compensate for errors.
Claim 23
Dependent Claim
83 words
A transmitter circuit for a high definition television signal, the circuit comprising: filter means arranged to split the signal into high and low frequency sub-bands: means for applying a non-linear pre-emphasis to the signal, the non-linear pre-emphasis characteristic being arranged to be complementary to a non-linear de-emphasis characteristic to be applied at the receiver end; and wherein the circuit provides digital processing; and further comprising: pre-corrector circuitry for applying a pre-correction function to the signal before filtering and pre-emphasis to compensate for errors.
Claim 24
Dependent Claim
44 words
A transmitter circuit in accordance with claim 19 and wherein the pre-corrector circuitry comprises means for filtering the signal to provide at least two frequency bands; means for applying a non-linear function to one of the bands; and means for recombining the frequency bands.
Claim 25
Dependent Claim
62 words
A transmitter circuit in accordance with claim 19 and wherein the means for applying a non-linear pre-emphasis to the signal also applies a function of the form: VO=Ve.sup.(q/KTM) (Vi-VO) -Ve.sup.-(q/KTM) (Vi-VO) (where Vi is the input voltage; VO is the output voltage; q is the electron charge; K is Boltzman's constant T is absolute temperature; and V and M are shape factors).
Claim 26
Dependent Claim
53 words
A method of processing in accordance with claim 20 and wherein the non-linear pre-emphasis is of the form: VO=Ve.sup.(q/KTM) (Vi-VO) -Ve.sup.-(q/KTM) (Vi-VO) (where Vi is the input voltage; VO is the output voltage; q is the electron charge; K is Boltzman's constant T is absolute temperature; and V and M are shape factors).
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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) | 1994-06-24 | 1994-12-24 | 1995-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-24 | 1998-12-24 | 1999-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-24 | 2002-12-24 | 2003-06-25 | $7700.00 | Window Closed / Lapsed |