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matured and technology rapidly advanced, it has
been extended to many civilian applications such
as environment and habitat monitoring, home au-
tomation, traffic control, and more recently health-
care applications (Hung,(2003); Jovanov, (2003);
Gao, (2005); Kafeza, (2004);Varshney,(2005)). In
particular, WBAN (Wireless Body Area Network)
technology has recently significantly increased the
potential of remote healthcare monitoring systems
(e.g. Jovanov, 2005; O'Donovan, 2009; Yazdan-
doost, 2009). WBAN is a particular kind of WSAN
consisting of strategically placed wearable or
implanted (in the body) wireless sensor nodes that
transmit vital signs (e.g., heart rate, blood pressure,
temperature, pH, respiration, oxygen saturation)
without limiting the activities of the wearer. The
data gathered can be forwarded in real time to
the hospital, clinic, or central repository through
a LAN (Local Area Network), WAN (Wide Area
Network) or cellular network. Doctors and carers
can at a distance access this information to assess
the state of health of the patient. Additionally, the
patient can be alerted by using SMS, alarm, or
reminder messages. In a more advanced WBAN,
a patient's sensor can even use a neighbor sensor
to relay its data if the patient is too far away from
the central server (e.g. the hospital data storage).
This communication mode is called ''Multi-hop''
wireless transmission. Generally speaking, multi-
hop not only extends the communication distance
but also saves energy consumption since direct
sensor-server long distance wireless communica-
tion is avoided through hop-to-hop relay.
WBANs will become increasingly pervasive
in our daily lives. In many applications (e.g. fetal
electrocardiogram monitoring and tele-cardiolo-
gy), communication links carry vital information
between the patient and the monitoring devices
that needs to be transmitted in short “bursts”,
requiring a reliable connection. On the other
hand, low “sensitive” file transmissions (e.g. in
temperature or breath monitoring) can be delay
tolerant. One of the critical issues is to design an
appropriate wireless protocol solution providing
reliability, energy efficiency, scalability, reduced
packet losses and a timely delivery without failure.
Several variants of the AODV (Ad Hoc Dis-
tance Vector) protocol (Zhang, 2005) have been
proposed in the literature to improve the QoS
in wireless sensor networks. We highlight that
the existing protocols that utilize AODV as the
underlying routing mechanism consider only the
end-to-end bandwidth and the distance metrics.
Moreover, most proactive and reactive protocols
choose a route based on the number of hops to the
destination that may be inappropriate when there is
congestion. Although recent AODV modifications
include load balancing operations during the route
set up, once the path is fixed they cannot efficiently
deal with a dynamic environment such as is the
case with healthcare applications (Argyriou, 2006;
Choi, 2003; Jung, 2004; Lee, 2005; Pham, 2004;
Saigal, 2004; Yoo, 2004).
Recently, the opportunity of introducing router
cooperation in order to improve healthcare sys-
tem reliability has been suggested (see Zhong,
(2007) and reference therein). In this scenario,
we propose a routing protocol built on the top of
AODV based on a minimal router cooperation
where each node is available to route neighbor
patient/router packets. Specifically, through the
proposed algorithm a patient's sensor/router can
dynamically transfer packets from overloaded
nodes to underloaded or idle nodes to relay its
data to mitigate dynamic congestion phenomena.
The main contribution of this chapter is to show
the enhancement of performance of a wireless
E-Healthcare system through a minimal routing
cooperation. In particular, a performance evalu-
ation of an enhanced AODV cooperative routing
algorithm QBAR (Queue Based Ad hoc Routing
algorithm) for WBAN applications has been as-
sessed demonstrating good performance in terms
of reliability, packet losses, scalability and time
delays. This would be particularly important in a
future real time E-Healthcare application where
it will be increasingly necessary for the observed
event (or action e.g. SMS, alarm, or reminder mes-
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