Browsing by Author "Ozyer, Sibel T."

Now showing 1 - 2 of 2

Citation - WoS: 1
Optimal Energy Efficient Routing in Wireless Sensor Networks With Link Asymmetry
(Ieee, 2012) Ozyer, Sibel T.; Tavli, Bulent; Koyuncu, Murat; Information Systems Engineering; 06. School Of Engineering; 01. Atılım University
In Wireless Sensor Networks (WSNs), link unidirectionality is an unavoidable phenomenon. The existence of unidirectional links can be attributed to several physical factors induced by the transceiver characteristics as well as other environmental phenomena. Transmission power heterogeneity is the dominant paradigm that leads to unidirectionality. In this study, we investigate the effects of transmission power heterogeneity on the lifetime of WSNs through a novel Linear Programming (LP) framework both for networks that utilize only bidirectional links and for those that can use unidirectional links in addition to bidirectional links. Our results show that transmission power heterogeneity can lead to more than 25 % decrease in network lifetime for protocols that can operate only on bidirectional links when compared to a network without any heterogeneity. However, if the use of unidirectional links is also enabled then, the decrease in network lifetime is at most 12 %.
Citation - WoS: 4
Citation - Scopus: 6
Systematic Investigation of the Effects of Unidirectional Links on the Lifetime of Wireless Sensor Networks
(Elsevier, 2013) Ozyer, Sibel T.; Tavli, Bulent; Dursun, Kayhan; Koyuncu, Murat; Information Systems Engineering; 06. School Of Engineering; 01. Atılım University
Link unidirectionality is a commonly encountered phenomenon in wireless sensor networks (WSNs), which is a natural result of various properties of wireless transceivers as well as the environment. Transmission power heterogeneity and random irregularities are important factors that create unidirectional links. Majority of the internode data transfer mechanisms are designed to work on bidirectional links (i.e., due to the lack of a direct reverse path, handshaking cannot be performed between a transmitter and receiver) which render the use of unidirectional links infeasible. Yet, there are some data transfer mechanisms designed specifically to operate on unidirectional links which employ distributed handshaking mechanisms (i.e., instead of using a direct reverse path, a multi-hop reverse path is used for the handshake). In this study, we investigate the impact of both transmission power heterogeneity and random irregularities on the lifetime of WSNs through a novel linear programming (LP) framework both for networks that utilize only bidirectional links and for those that can use bidirectional links as well as unidirectional links. (C) 2013 Elsevier B.V. All rights reserved.