مطالعه عددی مصرف انرژی و بهره وری زمان از شبکه های سنسور با توپولوژی های ساختاری مختلف و روش های مسیریابی

This paper reports a numerical study of energy consumption and time efficiency of sensor networks with five different structural topologies and four different routing methods, regarding their performances and costs, which might provide some references and guidelines for designing sensor networks under various conditions for possible applications.

Complex networks, deferring from traditional regular or random networks, have more complex architectures in general [1]. Recent work on analyzing network structures has found that many real-world networks are small-world networks or scale-free networks because the statistical analyses of many real datasets highly fit to such mathematical models. Watts and Strogatz [2] and [3] found that many networks have a common feature from the small-world model. Barabás and Albert [4] mapped the topology of the World Wide Web to a scale-free model. Faloutsos et al. [5] showed that some power-law relationships exist in the Internet topology. Jeong et al. [6] found the large-scale organization of metabolic networks to follow a power-law in node-degree distribution. Newman [7] pointed out that the structure of scientific collaboration network also has a scale-free degree distribution. These coincident findings in various disciplines provided great insights to and confidence on further studying more general mathematical network models which, in turn, offer useful tools for in-depth studies of real-world networks regarding their degree distributions, average shortest paths, cluster coefficients, community structures, Laplacian spectra, and so on [8], [9], [10], [11] and [12]. In addition to the aforementioned common structural features, many complex networks share another feature that the nodes are resource-limited. Examples include the Internet which consists of finite-buffer network devices, cooperation networks which are composed of time-limited people, and wireless sensor networks which are constituted of self-powered sensors. Therefore, studying resource-limited networks is quite important from an engineering point of view. In this paper, wireless sensor network is chosen as a reprehensive to investigate its energy consumption and lifetime performances in common interest.

This paper has shown extensive simulation results on energy consumption and lifetime efficiency of sensor networks on five different structural topologies with four different routing methods, by comparing their energy and lifetime performances. As is well known, routing method is the most important factor affecting the lifetime of a network. For network designers, if the network topologies are fixed, a random walk with memories is shown to be the best choice to prolong the lifetime of the networks. Also, when running a random walk scheme, the difference due to different topologies is less than that of the other schemes. Thus, it becomes clear that the network topology is the second important factor affecting the lifetime of a network, regarding which scale-free networks are the best among the tested topologies. Compared to both topologies and schemes, the distribution of initial energy has less influence in general. Needless to say, sensor networks constitute a large field of intensive research today, where there are many different network models and many different routing methods available. A few related methods include: LEACH [21], PEGASIS [22], FA [23], and SOR [24]. This paper is unable to compare to other routing methods, especially on different network topologies, which will be further examined, simulated and analyzed in the future. It is expected that the finding of this study might provide some references and guidelines for designing sensor networks under various conditions for different applications.