Pulse or digital communications – Equalizers – Automatic
Reexamination Certificate
2007-08-28
2007-08-28
Odom, Curtis B. (Department: 2611)
Pulse or digital communications
Equalizers
Automatic
C375S232000, C375S234000
Reexamination Certificate
active
10390366
ABSTRACT:
Optimal Decision Feedback Equalizer (DFE) coefficients are determined from a channel estimate by casting the DFE coefficient problem as a standard recursive least squares (RLS) problem and solving the RLS problem. In one embodiment, a fast recursive method, e.g., fast transversal filter (FTF) technique, is used to compute the Kalman gain of the RLS problem, which is then directly used to compute MIMO Feed Forward Equalizer (FFE) coefficients. The FBE coefficients are computed by convolving the FFE coefficients with the channel impulse response. Complexity of a conventional FTF algorithm may be reduced to one third of its original complexity by selecting a DFE delay to force the FTF algorithm to use a lower triangular matrix. The length of the DFE may be selected to minimize the tap energy in the FBE coefficients or to ensure that the tap energy in the FBE coefficients meets a threshold.
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Broadcom Corporation
Garlick Bruce E.
Garlick & Harrison & Markison
Odom Curtis B.
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