Patent ID: 8885699

Claim:
A method of operating an unrolled Decision Feedback Equalizer (DFE) having a plurality of input samplers, the method comprising: a) creating a reduced set of compensation factors (R) based on an original set of compensation factors (K N ) for the unrolled DFE, where R<K N , and where K represents number of bits encoded into each baud, and N represents the DFE depth in number of bauds; b) applying the reduced set of compensation factors as input sampler thresholds for the plurality of input samplers to generate a reduced set of unrolled DFE decisions, the number of input samplers being no more than R; and c) selecting an appropriate DFE decision from the reduced set of unrolled DFE decisions based upon previous bit values and in accordance with a mapping table, wherein step a) comprises: a0) merging the original set of compensation factors until their number reaches a pre-defined target R and keeping track of which levels in the original set of compensation factors were merged together; and a1) computing a mapping function to map between the previous bit values and the new input sampler thresholds; creating the mapping table based on the mapping function; and assigning values of a mapping table by assigning an increasing index value for each unique value of the unique index list.