Patent ID: 7409003

Claim:
A method for implementing adaptive Tomlinson-Harashima precoding using a digital data communications link, the method comprising: coding outgoing bit stream into symbols in a transmitter ( 1 ), correcting channel distortion by preceding the symbols in the transmitter ( 1 ), using Tomlinson-Harashima precoding employing coefficient parameter values, sending the precoded symbols over a data communications channel ( 2 , CHN) to a receiver ( 3 ), in which the symbols, which have passed through the signal processing means of the channel ( 2 , CHN) and the receiver ( 3 ), are reconstructable to form a bit stream, wherein at least one set of new coefficient parameter values are formed for the precoder (TML) with the aid of an error variable (e), which is formed using the symbol decisions (S′) of the receiver ( 3 ) and a signal (Q) that is obtained by compensating the effect of the precoder transfer function from the received signal with an inverse precoder transfer function.