Pulse or digital communications – Equalizers – Automatic
Reexamination Certificate
2008-07-15
2008-07-15
Vo, Don N (Department: 2611)
Pulse or digital communications
Equalizers
Automatic
C375S350000
Reexamination Certificate
active
07400677
ABSTRACT:
A method and apparatus is disclosed to overcome the effects of intersymbol interference during data transmission. Overcoming the effects of intersymbol interference makes possible higher data transmission rates for a given error rate. In one embodiment a receiver-transmitter pair is configured with a precode filter at the transmit side and a feed forward filter and a feedback filter at the receive side. Filter coefficients are calculated to reduce the undesirable effects of the channel, such as intersymbol interference. In one embodiment a training process occurs with the feedforward filter and a feedback filter, such that the first N coefficients of the feedback filter are set to zero. Thereafter, the coefficients of the feedforward filter are subject to spectral factorization and separated into minimum phase roots and maximum phase roots. The minimum phase roots comprise the precode filter coefficients and the maximum phase roots are established as feedforward filter coefficients.
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Solarflare Communications, Inc.
Vo Don N
Weide & Miller Ltd.
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