Patent ID: 9065696
Filing Date: 2015-06-23
Classification: H04L

Abstract:
1. An equalizer, comprising: equalizer circuitry configured to output an equalized signal in response to an input signal, a plurality of gain control signals, and a plurality of dither control signals, the equalizer circuitry having a plurality of taps, each tap controlled by a set of control signals comprising one of the plurality of gain control signals and one of the plurality of dither control signals; a mean squared error (MSE) system configured to provide an output MSE value in response to the equalized signal during each of a plurality of cycles; and adaptive control logic configured to adjust the plurality of gain control signals and the plurality of dither control signals in response to an MSE value, the adaptive control logic configured to select the plurality of taps in a predetermined sequence over the plurality of cycles, wherein the adaptive control logic is configured to determine whether the output MSE value is less than a best MSE value following adjustment of the set of control signals controlling a selected tap during one of the plurality of cycles, the adaptive control logic further configured to set the best MSE value to the output MSE value and to adjust a gain control signal controlling the selected tap during a cycle if it is determined that the output MSE value is less than the best MSE value, and wherein if the adaptive control logic determines that the output MSE value is less than the best MSE value following adjustment of the set of control signals controlling a selected tap, then before selecting a next tap of the plurality of taps in the predetermined sequence during a next cycle the adaptive control logic adjusts the dither control signal to a different dither value and determines whether the output MSE value in response to the different dither value is less than the best MSE value, wherein the adaptive control logic is further configured to iteratively adjust a limiting path signal swing in the MSE system and determine whether adjusting the limiting path signal swing results in a decrease in an amplitude difference between a limiting path signal and a linear path signal in the MSE system.