Research On Data Gathering Protocols For Energy-Harvesting Wireless Sensor Networks

Wireless Sensor Networks (WSN) is one of the rapidly developed technologies and owns prosperous application foregrounds. The energy restrain issue, however, set limitations for the WSN to its large-scaled, as well as long-time application scenarios, which is highly focused in the researching fields recent years. Through harvesting environment energy, especially the solar energy, to charge the wireless sensors is an reliable means to maintain its proper work currently, but many of the classic data harvesting protocols were not suitable for the wireless sensors which are embarked with solar energy harvesting modules. Therefore, to research how to design the reasonable data harvesting protocols based on the energy harvesting wireless sensor networks to maximize the utility of the network as well as to prolong the lifetime of WSN, has a great significance.The basic characteristics of wireless sensor networks were outlined in this paper, and some classical data harvesting protocols like Directed Diffusion, LEACH and Opportunistic Routing were also analyzed with a conclusion that all those protocols were not suitable for the wireless sensors which are embarked with solar energy harvesting modules. Through theoretical analysis, SRS, a data harvesting protocol based on region scheduling was proposed, and its mathematic model and energy model were also discussed in this paper. Besides, the topology structure of SRS was extended to two dimensional planar to fit in practical uses. Next, by anatomizing the shortcomings of SRS, the dynamic region scheduling, or DRS was pulled up. Compared with SRS, the DRS had uprated in data transmission path, identifier of data packet and data processing missions for achieving the goal of maximizing the energy utility and prolonging the lifetime of WSN. The mathematic model and energy model of DRS were also analyzed in this paper.The simulation results had proved that the SRS and DRS were excelled in the delivery rate of nodes, effective outputs, transmission redundancies, energy consumption ratio and the number of survived nodes with the other three data harvesting protocols like Directed Diffusion, LEACH and Opportunistic Routing, which means the SRS and DRS are properly suitable for the wireless sensor networks equipped with solar energy harvesting modules.