Mutual Information and Energy Tradeoff in Correlated Wireless Sensor Networks

We consider comparison of Mutual Information (MI)-Energy tradeoff in correlated wireless sensor network (WSN) for cooperative multiple input and multiple output (MIMO) and non-cooperative (referred to as single input and single output (SISO)) transmission schemes. Our numerical results indicate that for short distances SISO schemes achieve better Mi-Energy tradeoff than the cooperative MIMO schemes, while for long distances the cooperative MIMO schemes achieve better Mi-Energy tradeoff. We next consider the issue of sensor placement in a correlated WSN. Specifically, we prove that the spacing between nodes to maximize MI is in general an increasing function of observation SNR. From this structural result, we conclude that at high SNR, the various stages of the WSN can be separated by relatively large distances than at low SNR.