On the Limitations of Cooperation in Wireless Networks

Cooperation in a large wireless network (such as a cellular system) is shown to have certain fundamental limitations: namely, even perfect cooperation cannot in general change an interference-limited network to a noise-limited one. In contrast to existing literature that routinely assumes that the spectral efficiency scales with log P as the transmit power P grows large, the authors show the existence of a spectral efficiency upper bound that does not grow with P. The result uses well-accepted principles of information theory to reach the conclusion that it is not possible (or even helpful) to fully coordinate a large wireless network.