| 摘要 |
The present invention relates to a method for jointly processing signals (U) to be transmitted over respective ones of a plurality of subscriber lines (L1 to L4) through a non-linear precoder (21). The non-linear precoder comprises a first non-linear precoding stage (301; 301') configured to operate according to a first triangular precoding matrix (L; M; N) and including a modulo unit (Γ; γ), followed by a second linear precoding stage (302; 302') configured to operate according to a second precoding matrix (Q; P). in accordance with an embodiment of the invention, the method comprises organizing the plurality of subscriber lines into a first group of subscriber lines (GA) and a second group of subscriber lines (GB), the first group of subscriber lines at least comprising all the subscriber lines of the plurality of subscriber lines that do not support non-linear precoding operation (L2; L4) and the second group of subscriber lines comprising the remaining subscriber lines of the plurality of subscriber lines (L1; L3), scaling first signals (UA) to be transmitted over respective ones of the first group of subscriber lines to confine respective intermediate transmit power levels at the input of the modulo unit and further to bypass or make ineffective the operation of the modulo unit, and processing the so scaled first signals (UA') and second signals (UB) to be transmitted over respective ones of the second group of subscriber lines through the first and second precoding stages. The present invention also relates to a non-linear precoder (21). |
