Patent ID: 6675184
Filing Date: 2004-01-06
Classification: H04L

Abstract:
An adaptive type signal estimator comprising:an estimation signal storage unit for outputting a first sample signal to which nonlinear distortion is added; a convolution arithmetic unit for adding linear distortion to the first sample signal and outputting a signal as a second sample signal; a branch metric arithmetic unit for generating a branch metric used for Viterbi algorithm operation from a reception signal and the second sample signal, and outputting the branch metric; a signal determination unit for outputting a determination signal by performing maximum-likelihood sequence estimation using an output from said branch metric arithmetic unit on the basis of a Viterbi algorithm; and a coefficient corrector for receiving the first sample signal, the reception signal, and the determination signal, and outputting data correcting the second sample signal output from said convolution arithmetic unit, wherein said coefficient corrector obtains a difference signal on the basis of a replica generated from the determination signal and the first sample signal and a delayed reception signal obtained by delaying the reception signal by a predetermined period of time, obtains a product signal by multiplying the difference signal by a convergence factor, updates an impulse response value by using the product signal, and outputs the updated impulse response value to said convolution arithmetic unit.