Power consumption management for multicarrier arrangements

Abstract

An arrangement for use in a telecommunication system includes a binder of subscriber lines, a local transceiver circuit, and a far-end crosstalk cancellation circuit. Each of the subscriber lines ends at one of a plurality of remote user terminals. The local transceiver circuit is associated with the binder of subscriber lines and comprises a plurality of substantially identical transceiver modules, each of the transceiver modules being associated to one or a small number of subscriber lines. The far-end crosstalk cancellation circuit is configured to reduce far-end crosstalk between the subscriber lines of the binder, and is operably connected to interface with at least parts of the received data of the respective local transceiver modules. The far-end crosstalk cancellation circuit operable to implement a blind training algorithm for at least one victim subscriber line based on signals received by the respective associated transceiver modules.

1 . An arrangement for use in a telecommunication system, comprising:
 a local transceiver circuit comprising a plurality of substantially identical transceiver modules; and   a far-end crosstalk cancellation circuit configured to reduce far-end crosstalk, the far-end crosstalk cancellation circuit operably connected to interface with at least parts of received data of respective local transceiver modules, the far-end crosstalk cancellation circuit operable to implement an algorithm for at least one victim subscriber line based on signals received by other transceiver modules.   
     
     
         2 . The arrangement of  claim 1 , wherein the far-end crosstalk cancellation circuit is arranged as a chip-integrated canceller unit that is separate from the transceiver modules. 
     
     
         3 . The arrangement of  claim 1 , wherein each of the transceiver modules at an input side comprises a Fast Fourier Transform unit, an output of the Fast Fourier Transform unit being connected to a data input of the far-end crosstalk cancellation circuit. 
     
     
         4 . The arrangement of  claim 1 , wherein the far-end crosstalk cancellation circuit comprises:
 a plurality of multipliers for weighing at least a part of input signals received from respective associated transceiver modules with a complex coefficient; and   a subtracting unit having an input connected to outputs of the multipliers, the subtracting unit configured to subtract the weighed input signals from neighboring lines from the received signal data on a subscriber line which is subject to far-end crosstalk cancellation.   
     
     
         5 . The arrangement of  claim 1 , wherein the system comprises a synchronized DSL system. 
     
     
         6 . The arrangement of  claim 1 , wherein the system comprises a VDSL2 system. 
     
     
         7 . An arrangement for use in a telecommunication system, comprising:
 a local transceiver circuit comprising a plurality of substantially identical transceiver modules; and   a far-end crosstalk pre-compensation circuit configured to pre-compensate far-end crosstalk, the far-end crosstalk pre-compensation configured to interface with at least parts of transmitted data of respective local transceiver modules, the far-end crosstalk pre-compensation circuit to implement an algorithm for at least one victim subscriber line for training the far-end crosstalk pre-compensation circuit with respect to signals transmitted by the respective other transceiver modules and with information from the remote transceiver of the victim subscriber line.   
     
     
         8 . The arrangement of  claim 7 , wherein the far-end crosstalk cancellation circuit is arranged as a chip-integrated canceller unit which is separate from transceiver modules. 
     
     
         9 . The arrangement of  claim 7 , each of the transceiver modules at an output side comprises an Inverse Fast Fourier Transform Unit, an input of the inverse Fast Fourier Transform Unit being connected to a data output of the far-end crosstalk pre-cancellation circuit. 
     
     
         10 . An arrangement for use in a telecommunication system, comprising:
 a local transceiver circuit comprising a plurality of substantially identical transceiver modules, each of the modules being associated with at least one channel; and   a far-end crosstalk cancellation circuit configured to at least partly cancel far-end crosstalk between channels, the far-end crosstalk cancellation circuit associated with at least part of the local transceiver circuit, and wherein an algorithm for at least one victim data channel is implemented for training the far-end crosstalk cancellation circuit.   
     
     
         11 . The arrangement of  claim 10 , wherein the far-end crosstalk cancellation circuit is arranged as a chip-integrated canceller unit which is separate from chip-integrated transceiver modules. 
     
     
         12 . The arrangement of  claim 10 , wherein each of the transceiver modules at an input side comprises a Fast Fourier Transform unit, an output of the Fast Fourier Transform unit being connected to a data input of the far-end crosstalk cancellation circuit. 
     
     
         13 . The arrangement of  claim 10 , wherein the far-end crosstalk cancellation circuit comprises:
 a plurality of multipliers, each configured to weigh at least a part of an input signal with a complex coefficient, and a subtracting unit having an input of which is connected to the outputs of the multipliers.   
     
     
         14 . A method of operating a telecommunication system, the system comprising a binder of subscriber lines originating from a switch and operably coupled to a plurality of user terminals, the method comprising:
 performing dedicated far-end crosstalk cancellation on predetermined selected subscriber lines of the binder, at the end of a switch and/or at the end of selected user terminals.   
     
     
         15 . The method of  claim 14 , wherein the system is an xDSL-type system and the step of performing dedicated far-end crosstalk cancellation further comprises; performing an initial training of relevant correction coefficients corresponding to crosstalk cancellation for a first subscriber line during a Quiet Phase of the first subscriber line. 
     
     
         16 . The method of  claim 14 , wherein the system is an xDSL-type system and the step of performing dedicated far-end crosstalk cancellation further comprises: updating relevant correction coefficients corresponding to a crosstalk cancellation for a first subscriber line during reception of a synchronization symbol of the first subscriber line. 
     
     
         17 . The method of  claim 14 , further comprising performing initial training for at least a first subscriber line, the initial training using one of a group of algorithms consisting of a least-mean-squared (LMS) algorithm, a sign-LMS algorithm, and a sign-sign-LMS algorithm. 
     
     
         18 . The method of  claim 16 , wherein the update of the far-end crosstalk cancellation coefficients is carried out using one of a group of algorithms consisting of a least-mean-squared (LMS) algorithm, a sign-LMS algorithm, and a sign-sign-LMS algorithm. 
     
     
         19 . A method of operating a telecommunication system, the system comprising a plurality of channels between a switch and a plurality of user terminals, the method comprising:
 performing dedicated far-end crosstalk cancellation on predetermined channels, at the end of a switch and/or at the end of selected user terminals.   
     
     
         20 . The method of  claim 19 , wherein the system is an xDSL-type system and the step of performing dedicated far-end crosstalk cancellation comprises performing an initial training of relevant correction coefficients during a Quiet Phase of a respective channel. 
     
     
         21 . The method of  claim 19 , wherein the system is an xDSL-type system and the step of performing dedicated far-end crosstalk cancellation comprises performing an update of relevant correction coefficients during reception of a synchronization symbol of a respective channel. 
     
     
         22 . The method of  claim 20 , wherein the initial training is carried using one of a group of algorithms consisting of a least-mean-squared (LMS) algorithm, a sign-LMS algorithm, and a sign-sign-LMS algorithm. 
     
     
         23 . The method of  claim 21 , wherein the update of the far-end crosstalk cancellation coefficients is carried out using one of a group of algorithms consisting of a least-mean-squared (LMS) algorithm, a sign-LMS algorithm, and a sign-sign-LMS algorithm.