Abstract:
On Network Lifetime Maximization in Wireless Sensor Networks with
Sink Mobility
Wireless Sensor Networks (WSNs) extend human capability to monitor and control
the physical world, especially, in catastrophic/emergency situations where human
engagement is too dangerous. There is a diverse range of WSN applications
in terrestrial, underwater and health care domains. In this regard, the wireless
sensors have significantly evolved over the last few decades in terms of circuitry
miniaturization. However, small sized wireless sensors face the problem of limited
battery/power capacity. Thus, energy efficient strategies are needed to prolong the
lifetime of these networks. This dissertation, limited in scope to routing only, aims
at energy efficient solutions to prolong the lifetime of terrestrial sensor networks
(i.e., WSNs) and Underwater WSNs (UWSNs).
In WSNs, we identify that uneven cluster size, random number of selected Cluster
Heads (CHs), communication distance, and number of transmissions/receptions
are mainly involved in energy consumption which lead to shortened network
lifetime. As a solution, we present two proactive routing protocols for circular
WSNs; Angular Multi-hop Distance based Clustering Network Transmission
(AM-DisCNT) and improved AM-DisCNT (iAM-DisCNT). These two protocols
are supported by linear programming models for information flow maximization
and packet drop minimization. For reactive applications, we present four routing
protocols; Hybrid Energy Efficient Reactive (HEER),Multi-hop Hybrid Energy Efficient
Reactive (MHEER), HEER with Sink Mobility (HEER-SM) and MHEER
with Sink Mobility (MHEER-SM). The multi hop characteristic of the reactive
protocols make them scalable. We also exploit node heterogeneity by presenting
four routing protocols (i.e., Balanced Energy Efficient Network Integrated Super
ix
Heterogeneous (BEENISH), Mobile BEENISH (MBEENISH), improved BEENISH
(iBEENISH) and improved Mobile BEENISH (iMBEENISH)) to prolong the
network lifetime. Since the problems of delay tolerance and mobile sink trajectories
need investigation, this dissertation factors in four propositions that explore
defined and random mobile sink trajectories. On the other hand, designing an
energy efficient routing protocol for UWSNs demands more accuracy and extra
computations due to harsh underwater environment. Subject to nodes’ energy
consumption minimization, we present Autonomous Underwater Vehicle (AUV)
and Courier Nodes (CNs) based routing protocol for UWSNs. We validate our
propositions for both WSNs and UWSNs via simulations. Results show that the
proposed protocols where we incorporated sink mobility perform better than the
existing ones in terms of selected performance metrics.