A sun energy harvester model for the network simulator 3 (ns-3)

Machine to machine communications (M2M) areretained as one of the most important enabling technologies forthe fulfilment of the Smart City paradigm. Unfortunately, M2Mcommunications are still far to be a fully viable technology.One of the most important research topics concerning M2M ishow to extend, as long as possible, the lifetime of the devicesinvolved in the communication process by: (i) reducing the energyconsumption and, (ii) using an harvesting system as an optionalcapability to recharge the devices. However, one important issuehindering the research advancement of this topic is the lackof an accurate simulation environment. Although the networksimulator-3 (ns-3) offers many features to resolve that issue, thenatively embedded models of energy harvesting systems are verysimple and fail to take into account many aspects of the harvestingprocess. In this paper, we focus on solar energy harvesting systemsand we propose an extension to ns-3 to accurately model them.Through simulation results, we show how our model allows torealistically simulate the behaviour of the devices powered bysolar energy harvesters with different time scales ranging froma few seconds to several days.