Energy dissipation characteristics of Wireless Sensor Networks with unidirectional links

Link unidirectionality is a commonly encountered phenomena in Wireless Sensor Networks (WSNs), which is a natural result of various properties of wireless transceivers as well as the environment. Transmission power heterogeneity is the dominant factor that creates unidirectional links. In this study, we investigate the impact 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 bidirectional links as well as unidirectional links. Our results show that transmission power heterogeneity can lead to more than 25% decrease in network lifetime for networks that utilize only 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%.