Exploiting spatial diversity in cooperative copper units

The paper explains how spatial diversity can be exploited by cooperative copper units (CCU) to increase the Shannon capacity in a crosstalk dominated environment. Contrary to the rank instability of the frequency dispersive wireless channel, CCU always experience full rank MIMO channels. Nevertheless, the major gain inherent in CCU optimal joint processing does not stem from the channel full rank property but from the pair-to-pair alien crosstalk correlation. For that purpose, the probability distribution of the normalized correlation coefficient is modeled by a beta probability distribution. Limited to just two pairs, MIMO-CCU operates either in full multiplexing (FM) or full diversity (FD) modes, transmitting independent or identical data streams.