US 8,558,955 B2 · Cable equalization locking

Abstract

Provided herein are methods and systems that provide automatic compensation for frequency attenuation of a video signal transmitted over a cable. In accordance with an embodiment, a system includes an equalizer and a compensation controller. The equalizer receives a video signal that was transmitted over a cable, provides compensation for frequency attenuation that occurred during the transmission over the cable, and outputs a compensated video signal. The compensation controller automatically adjusts the compensation provided by the equalizer based on comparisons of one or more portions of the compensated video signal to one or more reference voltage levels. The compensating is selectively locked and reset in response to specific conditions being detected, e.g., a locking condition and a reset condition.

Claims11

Dependent claims

A system to provide automatic compensation for frequency attenuation of a video signal transmitted over a cable, comprising:

an equalizer that receives a video signal that was transmitted over a cable, provides compensation for frequency attenuation that occurred during the transmission over the cable, and outputs a compensated video signal, wherein the equalizer includes
a high band equalizer that compensates for high frequency attenuation caused by the cable;
a low band equalizer that compensates for low frequency attenuation caused by the cable;
and
a DC gain controller that fine tunes DC gain of the equalizer;
and
a compensation controller that automatically adjusts the compensation provided by the equalizer based on comparisons of one or more portions of the compensated video signal to one or more reference voltage levels;
wherein the compensation controller automatically adjusts the compensation provided by the equalizer by automatically controlling the high band equalizer, the low band equalizer and the DC gain controller;
and
wherein the compensation controller locks the compensation provided by the high band equalizer, the low band equalizer and the DC gain controller in response to detecting a lock condition.

7 more elements

A method for providing automatic compensation for frequency attenuation of a video signal transmitted over a cable, comprising:

(a) compensating for frequency attenuation that occurred during the transmission of the video signal over the cable to thereby produce a compensated video signal;
(b) comparing one or more portions of the compensated video signal to one or more reference voltage levels;
(c) automatically adjusting the compensating performed at step (a) based on results of the comparing performed at step (b);
and
(d) locking the compensating in response to a lock condition being detected;
wherein step (a) include:
(a.1) compensating for high frequency attenuation caused by the cable;
(a.2) compensating for low frequency attenuation caused by the cable;
and
(a.3) fine tuning DC gain;
wherein step (c) includes
(c.1) automatically adjusting the compensating for high frequency attenuation performed at step (a.1);
(c.2) automatically adjusting the compensating for low frequency attenuation performed at step (a.2);
and
(c.3) automatically adjusting the fine tuning of DC gain performed at step (a.3);
and
wherein step (d) includes automatically locking the compensating for high frequency attenuation, the compensation for low frequency attenuation and the fine tuning of the DC gain in response to the lock condition being detected.

14 more elements

Dependencies are inferred from the claim text.

Cable equalization locking

Life of this patent

Cable equalization locking

Life of this patent

Abstract

Claims11