Energy-Efficient Delay-Constrained Routing for
Sensor Networks with Low Duty Cycles
Lina Li
1,2
, Xiaohui Wei
1
, Hongliang Li
1 ∗
and Guodong Sun
3
1
College of Computer Science and Technology,JilinUniversity,Changchun,China
2
Department of Information Engineering,Jilin Economic Management Cadre College,Changchun,China
3
∗
lihongliang@jlu.edu.cn
Abstract—This paper investigates solutions for the delay-
constrained least-cost (DCLC) paths problem in low duty-cycled
sensor networks where nodes asynchronously sleep most of
their time. Solving DCLC problem in sensor networks is very
challenging not only because of its NP-Completeness, but because
of the stringent network resources. We propose an approximated
DCLC routing algorithm, called ADRA, which distributively
executes with a linear message complexity and a constant per-
node memory requirement, and achieves near-optimal solutions
as the network size or the radio range increases. Theoretical
analysis and extensive simulation evaluate our design.
Index Terms—Duty-cycled sensor network, routing, delay con-
straint, energy efficiency
I. INTRODUCTION
Wireless sensor network [1], [2] becomes a key research
field in past a few years, and it benefits many scenarios, such
as military surveillance[3], environment or assets monitoring
[4], [5], home healthcare[6], structural failure detection[7], [8],
and so on. A critical challenge is to prolong the system lifetime
of sensor networks. One major method of increasing longevity
of sensor networks is to reduce the duty cycles of nodes, i.e.,
let nodes keep a short period of active time to communicate
with others. Such a low duty-cycled sensor network, however,
makes the delay QoS guarantee be a significant challenge.
Even though some effort [9], [10], [11] has been put into
low duty-cycled sensor network to optimize the delivery delay,
or the energy efficiency, or the throughput, less attention has
been paid to optimizing a specific network performance while
meeting other constraints.
In this paper we focus on the energy-efficient routing for
low duty-cycled sensor networks with path delay constraint,
by jointly considering both metrics of the energy and delay of
path. Formally we investigate the delay-constrained least-cost
(DCLC) paths problem, an NP-Complete [12] one, to achieve
least-energy paths satisfying the delay constraint. In recent
years, there are many attempts [13], [14], [15] on the DCLC
problem for Internet and Ad hoc networks. Those work often
requires the centralized decision, or the support of end-to-end
message exchange, or the local maintenance of some global
network states, and hence can not be used in sensor networks
with scarce resources in computation and communication.
To overcome the limitations of the previous work, we
propose an approximated DCLC routing algorithm, called
ADRA to minimize the energy cost of paths under some delay
constraint in low duty-cycled sensor networks. Considering
the scalability requirement in terms of network size and node
density, ADRA is designed based on a non-linear, mixed
cost function which transforms the DCLC problem into a
two-constrained minimization problem. ADRA can execute
distributively with a linear message complexity and a O(1)
per-node memory requirement. Simulation results show that
ADRA returns near-optimal solutions as the network size or
the radio range increases.
The rest of this paper is organized as follows. Section II
introduces the background of duty-cycled sensor network as
well as the network model and assumptions used in this paper.
Section III gives the formal description of DCLC problem
to be addressed in this paper and then details the proposed
algorithm, with theoretical analysis in terms of complexity
and convergence. Section IV shows the simulation results and
analysis. We conclude this paper in section V.
II. B
ACKGROUND AND NETWORK MODEL
In this section we first introduce some backgrounds of the
duty-cycled mode adopted by many sensor network applica-
tions, which illustrate the necessity and importance of this
mode, and then present the network model and assumptions
used in our design and analysis.
A. Background
In wireless sensor networks node is often driven by the
constrained energy source, such as battery or capacitor be-
cause of the limitation of the size and cost. So it is very
critical to design energy-efficient schemes for prolonging the
system lifetime of sensor network. A sensor node can sample
the physical world and communicate with others nodes for
delivering its sensory data. A major method of extending
system lifetime is reducing the duty cycle of node such that the
node uses a short period of time to sample or communicate,
while sleeps for most of its time. This duty-cycling scheme
is reasonable because nodes are often redundantly deployed
in sensor network applications; in other words, nodes can
alternately wake up to work, without sacrificing the monitoring
fidelity. Additionally, for some applications, events have not to
be monitored all the time because they occurs periodically. In
our previous work [16], [17], for instance, which focuses on
monitoring corrosion in reinforced concrete structures, we find
2013 8th Annual ChinaGrid Conference
978-0-7695-5058-9/13 $26.00 © 2013 IEEE
DOI 10.1109/ChinaGrid.2013.27
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