Achievable rates for Gaussian relay networks with a supplementary non-broadcast link

Large system analysis has shown that per-node throughput in purely wireless networks goes to zero as the network size increases. Thus it appears the world will never be totally wireless. This motivates the study of a new kind of hybrid network composed both of purely broadcast wireless (RF) nodes and what we call multi modal nodes, i.e., nodes that can transmit simultaneously over broadcast wireless and other non-broadcast nodes, e.g., wires, infrared, or acoustic links. Here we present achievable rates for three terminal networks using DF, CF, and partial DF when one additional non-broadcast mode is available. We also provide rates for the special case of Gaussian channels.