Digital transmitter

Pulse or digital communications – Transmitters – Antinoise or distortion

Reexamination Certificate

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C375S229000, C333S02800T

Reexamination Certificate

active

07099404

ABSTRACT:
An equalizer provided in a digital transmitter compensates for attenuation in a signal channel to a digital receiver. The equalizer generates signal levels as a logical function of bit history to emphasize transition signal levels relative to repeated signal levels. The preferred equalizer includes an FIR transition filter using a look-up table. Parallel circuits including FIR filters and digital-to-analog converters provide a high speed equalizer with lower speed circuitry. The equalizer is particularly suited to in-cabinet and local area network transmissions where feedback circuitry facilitates adaptive training of the equalizer.

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