ADAPTIVE EQUALIZATION USING A CONDITIONAL UPDATE SIGN-SIGN LEAST MEAN SQUARE ALGORITHM

摘要

An adaptive equalizer finite impulse response (FIR) filter for high-speed communication channels with modest complexity, where the filter is iteratively updated during a training sequence by a circuit performing the update: (I), where (II) is the filter vector representing the filter taps of the FIR filter, (III) is the data vector representing present and past samples of the received data x(t), d(t) is the desired data used for training, z(t) is the output of the FIR filter, µ determines the memory or window size of the adaptation, and K is a scale factor taking into account practical limitations of the communication channel, receiver, and equalizer. Furthermore, a procedure and circuit structure is provided for calibrating the scale factor K.