Link-Correlation-Aware Opportunistic Routing in Low-Duty-Cycle Wireless Networks

Area of Science:

• Wireless Networking
• Network Protocols
• Energy Efficiency in Networks

Background:

• Opportunistic Routing (OR) is inefficient in low-duty-cycle networks due to unreliable, correlated links and misaligned node schedules.
• High energy consumption and poor transmission efficiency limit the application lifetime in such networks.

Purpose of the Study:

• To propose a novel node scheduling scheme (LDC-COR) for opportunistic routing in low-duty-cycle wireless networks.
• To improve performance by considering link correlation and link quality for node grouping and scheduling.
• To reduce energy consumption and enhance transmission efficiency.

Main Methods:

• Developed a polynomial-time node scheduling algorithm (LDC-COR) that groups nodes with low link correlation.
• Scheduled nodes within groups to wake up simultaneously for packet forwarding.
• Incorporated both link correlation and link quality into the scheduling decisions.
• Evaluated LDC-COR using extensive simulations and a physical wireless testbed with 20 TelosB nodes.

Main Results:

• LDC-COR significantly improves performance by aligning schedules of low-correlation nodes.
• The protocol enhances the expected transmission count (ETX) by considering link correlation and quality.
• Energy consumption in low-duty-cycle OR is substantially reduced.
• Minimal communication overhead is introduced as only one-hop neighbor information is required.

Conclusions:

• LDC-COR effectively bridges the gap between limited node energy resources and application lifetime requirements.
• The proposed scheme significantly improves transmission efficiency and reduces energy consumption for low-duty-cycle OR.
• A slight increase in end-to-end delay was observed, but overall performance gains are substantial.