Patent ID: 8565418

Claim:
A method for extending channels, comprising: generating a non-cascade extended channel by using a first channel and a second channel; and generating a first-level cascade extended channel by using the non-cascade extended channel and a third channel, wherein the first channel and the second channel are both twisted-pair channels, and the third channel is a twisted-pair channel or another non-cascade extended channel; wherein the number of the twisted-pair channels is N, a total number of all generated extended channels is M, wherein N and M are both natural numbers, and all the extended channels comprises non-cascade extended channels and cascade extended channels, the method further comprising: after receiving a signal from the N twisted-pair channels and the M extended channels, performing a crosstalk cancellation process on the received signal, wherein a crosstalk cancellation matrix used in the crosstalk cancellation process is a matrix of (N+M) rows and (N+M) columns on each sub-carrier; and when sending a signal to the N twisted-pair channels and the M extended channels, performing a vector precoding process on the signal and then sending the signal, wherein a vector precoding matrix used in the vector precoding process is a matrix of (N+M) rows and (N+M) columns on each sub-carrier.