Fig. 8From: Geographical model-derived grid-based directional routing for massively dense WSNsThe relative mean of routing cost of the scenario in Fig. 7: the mean of the routing cost of FM (or GADM) is the average cost of all nodes to the sink using the routing directions derived by FM (or GADM). The relative mean of FM (or GADM) is defined as the mean of the routing cost of FM (or GADM) divided by the mean of the optimum routing cost (OPT)Back to article page