Effect of channel correlation on the capacity scaling in wireless networks

A hierarchical cooperative multiple-input multiple-output (MIMO) transmission can greatly improve the throughput scaling in wireless networks as shown in [1]. In this paper, we analyze the effect of channel correlation on the throughput scaling in wireless networks by focusing on an achievable rate of the cooperative MIMO transmission between two clusters of nodes as a function of the number of nodes in each cluster, the physical size of each cluster, and the distance between the two clusters. Channel correlation occurs naturally in a regime when the effect of the wavelength cannot be ignored. We use a realistic channel model that can model this channel correlation accurately. Although it is not critical, we assume more generally multiple antennas are allowed per node since this assumption becomes natural for our channel model. Our main results are in a sense consistent with the upper bounds in [2], [3] on the degrees of freedom in MIMO and in wireless networks.