Optimal relay selection for transmission rate maximisation in multi-hop wireless networks

A fundamental problem for wireless networks is how to select relays from all available network nodes to realise the optimal multi-hop relaying between a source node and a destination node. Mutual interference among wireless nodes makes this problem challenging. A surprising result of the reported work is that interference-free multi-hop relaying can be achieved in full-duplex decode-and-forward relaying. The broadcast nature of wireless transmissions can be exploited without suffering from mutual interference. Then, an efficient relay selection algorithm is developed that finds the optimal hop count and all the relays to maximise the source-destination multi-hop transmission rate. The complexity of the algorithm is O(N²) only, where N is the number of available network nodes or network size. Interestingly, this wireless network algorithm is similar to the well-known Dijkstra´s algorithm of wired networks. Simulations are conducted to demonstrate its optimality and efficiency.