For node Sj to hear Si, we must have that: d (Si, Sj) �� r, and (xj, yj) ��i, where d (Si, Sj) is the Euclidean distance between nodes Si and Sj, and ��i is the scanning area of node Si. Two distinct sets of neighbors are defined for each node Si: the set FNeb(Si), known as Si’s forward neighborhood, Lenalidomide supplier contains all Inhibitors,Modulators,Libraries nodes that Si can talk to directly; and the set BNeb(Si), known as Si’s backward neighborhood, includes all nodes that can directly talk to Si. In Figure 3(b), Sj is a successor of Si and Si is a predecessor of Sj [9]. Si can get to Sj by one hop transmission, but Sj has to visit Sa and Sb before reaching to Si.Figure 3.(a) Network parameter; (b) Sj can talk to Si through multiple hops Sj��Sa��Sb��Sj.The design of algorithms and protocols for FSOSNs is very challenging.
First, though current technology continues to drive the advances in sensor fabrication, including processing design and computing, advances of battery technology still lag behind, Inhibitors,Modulators,Libraries making energy resources the fundamental constraint in sensor networks, whether in RFSNs or FSOSNs. Besides, because of the large amount of nodes, recharging the battery when exhausted is unpractical for sensor network applications, particularly for those operating in hostile environments like volcanoes and swarms. Moreover, especially for FSOSNs, the property of directionality demands high network connectivity for data communication. For example, as the time goes by during data transmission, when a certain sensor node died of the depletion of energy, the network Inhibitors,Modulators,Libraries connectivity would probably drop dramatically, because the BS would lose contact with those nodes that had to go through the dead one for up-link communication.
Any data originated from these nodes was meaningless and wasting energy. As a consequence, power and connectivity management becomes a main ingredient in the design of algorithms and protocols.A recent trend in wireless directional communication aims at leveraging the smart antenna, which either consists of N beam patterns or can dynamically change the direction of the beam [10,11]. Inspired Inhibitors,Modulators,Libraries by this technology, we assume that the sensor nodes in our work are able to reconfigure their direction of the active transmitter during data transmission. Accompanied with the leverage of localization techniques such as global positioning system (GPS) [12], in this paper, we propose a reconfigurable routing protocol (RRP) for FSOSNs to achieve efficient data delivery and extended lifetime by network reconfiguration.
Brefeldin_A Specifically, RRP focuses on dynamically adjusting the orientation and communication radius of nodes during data transmission so as to maintain the network connectivity, guarantee packet delivery, and prolong lifetime. kinase inhibitor Dovitinib It works in three phases: (1) virtual topology construction, (2) routing establishment, and (3) reconfigurable routing.