Link-Correlation-Aware Opportunistic Routing in Wireless Networks

• Published in: IEEE transactions on wireless communications Vol. 14; no. 1; pp. 47 - 56
• Main Authors: Shuai Wang, Basalamah, Anas, Song Min Kim, Shuo Guo, Tobe, Yoshito, Tian He
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2015; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Computer networks; Correlation; Links; Mathematical analysis; Packet loss; Protocols; Receivers; Routing; Routing (telecommunications); Scheduling; Simulation; Wireless communication; Wireless networks; Opportunistic routing; wireless networks; protocol design; link correlation
• ISSN: 1536-1276; 1558-2248
• DOI: 10.1109/TWC.2014.2329568

Recent empirical studies have shown clear evidence that wireless links are not independent and that the packet receptions on adjacent wireless links are correlated. This finding contradicts the widely held link-independence assumption in the calculation of the core metric, i.e., the expected number of transmissions to the candidate forwarder set, in opportunistic routing (OR). The inappropriate assumption may cause serious estimation errors in the forwarder set selection, which further leads to underutilized diversity benefits or extra scheduling costs. We thus advocate that OR should be made aware of link correlation. In this paper, we propose a novel link-correlation-aware OR scheme, which significantly improves the performance by exploiting the diverse low correlated forwarding links. We evaluate the design in a real-world setting with 24 MICAz nodes. Testbed evaluation and extensive simulation show that higher link correlation leads to fewer diversity benefits and that, with our link-correlation-aware design, the number of transmissions is reduced by 38%.