Optimal power aware routing for Decode-and-Forward multi-hop relay networks

A novel cross-layer routing protocol is presented for Decode-and-Forward multi-hop relaying systems which lead to optimal power allocation for a given power budget by maximizing the capacity of source to destination. The problem of rate maximization by jointly allocating power and selecting relays nodes with limited total power constraint of network nodes is formulated when the channel state information (CSI) for all of the links is available and constant during the transmission. Showing the convexity of the problem we had separated the problem into two independent sub-problems without loss of optimality. The first problem related to power allocation and the second problem leads to standard routing problem. Our routing problem has introduced new routing metric which by using it we can hold optimality when applying power allocation to the selected route. Simulation results show that our power aware routing works well in middle SNR too. A comprehensive simulation setup is performed to analyze our algorithm in a realistic scenario which shows large performance gain over the previous power allocation (such as uniform power allocation) and other routing algorithms. Even significant gain is achieved when optimal power allocation or optimal routing algorithm are bundled with non-optimal version of each other.