Method for reducing echoes in television equalizer video signals and apparatus therefor

A television equalizer comprising:

• a first digital filter receiving a sampled video signal as an input and providing an output;
• a first summing node, coupled to the first digital filter, receiving the output of the first digital filter and providing an output signal of the equalizer;
• a second digital filter, coupled to the first summing node, receiving the output signal of the equalizer as an input and providing an output to the first summing node;
• a second summing node, coupled to the first summing node, receiving as inputs the output signal of the equalizer and a reference signal, and providing as an output an error signal equal to a difference between the output signal of the equalizer and the reference signal;
• and
• an echo suppression circuit, coupled to the first and second digital filters, receiving as an input the error signal, selecting more significantly valued filtered coefficients of the first and second filters, adaptively updating the selected filter coefficients and providing the updated filter coefficients to the first and second filters to reduce the error signal.

A television equalizer comprising:

• first filter means, receiving a sampled video signal as an input and providing an output;
• first summing means, coupled to the first filter means, receiving the output of the first filter means and providing an output signal of the equalizer;
• second filter means, coupled to the first summing means, receiving the output signal of the equalizer as an input and providing an output to the first summing means;
• second summing means, coupled to the first summing means, receiving as input the output signal of the equalizer and a reference signal, and providing as an output an error signal equal to the difference between the output signal of the equalizer and the reference signal;
• and
• echo suppression means, coupled to the first and second filter means, receiving as an input the error signal, selecting more significantly valued filter coefficients of the first and second filter means, adaptively updating the selected coefficients, and providing the coefficients to the first and second filter means to reduce the error signal.