Dynamic duty cycle control for end-to-end delay guarantees in wireless sensor networks

• Published in: 2010 IEEE 18th International Workshop on Quality of Service (IWQoS) pp. 1 - 9
• Main Authors: Xiaodong Wang, Xiaorui Wang, Guoliang Xing, Yanjun Yao
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.06.2010
• Subjects: Communication system control; Control systems; Costs; Delay effects; Dynamic scheduling; Energy efficiency; Feedback control; Runtime; Sleep; Wireless sensor networks
• DOI: 10.1109/IWQoS.2010.5542743
• ISBN: 1424459877; 9781424459872
• ISSN: 1548-615X

It is well known that periodically putting nodes into sleep can effectively save energy in wireless sensor networks, at the cost of increased communication delays. However, most existing work mainly focuses on static sleep scheduling, which cannot guarantee the desired delay when the network conditions change dynamically. In many applications with user-specified end-to-end delay requirements, the duty cycle of every node should be tuned individually at runtime based on the network conditions to achieve the desired end-to-end delay guarantees and energy efficiency. In this paper, we propose DutyCon, a control theory-based dynamic duty cycle control approach. DutyCon decomposes the end-to-end delay guarantee problem into a set of single-hop delay guarantee problems along each data flow in the network. We then formulate the single-hop delay guarantee problem as a dynamic feedback control problem and design the controller rigorously, based on feedback control theory, for analytic assurance of control accuracy and system stability. DutyCon also features a queuing delay adaptation scheme that adapts the duty cycle of each node to unpredictable packet rates, as well as a novel energy balancing approach that extends the network lifetime by dynamically adjusting the delay requirement allocated to each hop. Our empirical results on a hardware testbed demonstrate that DutyCon can effectively achieve the desired tradeoff between end-to-end delay and energy conservation. Extensive simulation results also show that DutyCon outperforms two baseline sleep scheduling protocols by having more energy savings while meeting the end-to-end delay requirements.