A predictive retransmission scheme for cooperative routing in intermittently connected sensor networks

Abstract

We consider energy harvesting sensor networks that are characterized by intermittent connectivity between sensor nodes due to random sleep and wake cycles caused by sporadic availability of energy sources. A retransmission strategy is developed that probabilistically predicts the best transmission interval between successive retransmissions in order to maximize the likelihood of successful packet delivery. We utilize this strategy for a cooperative routing approach to further improve the delay performance in such intermittently connected networks. An analytical model is formulated to study the delay characteristics of the proposed retransmission scheme. The performance of the proposed protocol in a multi-hop environment is evaluated through simulations. Results show that the retransmission scheme can provide significant performance improvements when compared to existing approaches.