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Abstract
Wireless Body Area Networks (WBANs) provide efficient communication solutions to the ubiquitous
healthcare systems. Health monitoring, telemedicine, military, interactive entertainment, and portable
audio/video systems are some of the applications where WBANs can be used. The miniaturized sensors
together with advance micro-electro-mechanical systems (MEMS) technology create a WBAN that
continuously monitors the health condition of a patient. This paper presents a comprehensive discussion
on the applications of WBANs in smart healthcare systems. We highlight a number of projects that enable
WBANs to provide unobtrusive long-term healthcare monitoring with real-time updates to the health
center. In addition, we list many potential medical applications of a WBAN including epileptic seizure
warning, glucose monitoring, and cancer detection.
Key Words: Wireless Sensor Networks (WSNs), Body Area Network (BAN), Body Sensor Networks
(BSNs), Healthcare and medical Applications, Smart Biosensor.

Introduction
Advances in wireless communication and micro-
electro-mechanical systems (MEMS) allow the
establishment of a large scale, low power, multi-
functional, and (ideally) low cost network. Wireless
sensor networks (WSNs) are finding applications in
many areas, such as medical monitoring, emergency
response, security, industrial automation,
environment and agriculture, seismic detection,
infrastructure protection and optimization,
automotive and aeronautic applications, building
automation, and military applications .Wireless
sensor networks can be effectively used in healthcare
to enhance the quality of life provided for the patients
and also the quality of healthcare services. For
example, patients equipped with a wireless body area
network (WBAN) need not be physically present at
the physician for their diagnostic. A body sensor
network proves to be adequate for emergency cases,
where it autonomously sends data about patient
health so that physician can prepare for the treatment
immediately.
The biosensor based approach to medical care makes
it more efficient by decreasing the response time, and
reducing the heterogeneousness of the application.
These sensors are implanted in the human body that
forms a wireless network between themselves and
some entities which are external to the human body.
A wired network requires laying wires within the
human body, which is not desirable therefore
wireless network, is the most suitable option. Such a
network can be used for a variety of applications.
These include both data aggregation and data
dissemination applications. Biosensors may be used
for monitoring the physiological parameters like
blood pressure, glucose levels and collecting the data
for further analysis. Wearable health monitoring
systems allow an individual to closely monitor
changes in her or his vital signs and provide feedback
to help maintain an optimal health status. If
integrated into a telemedical system, these systems
can even alert medical personnel when life-
threatening changes occur. During the last few years
there has been a significant increase in the number of
various wearable health monitoring devices, ranging
from simple pulse monitors, activity monitors, and
portable Holter monitors, to sophisticated and
expensive implantable sensor

Architecture
The proposed wireless body area sensor network for
health monitoring integrated into a broader multitier
telemedicine system is illustrated in Figure 1. The
telemedical system spans a network comprised of
individual health monitoring systems that connect
through the Internet to a medical server tier that
resides at the top of this hierarchy. The top tier,
centered on a medical server, is optimized to service
hundreds or thousands of individual users, and
encompasses a complex network of interconnected
services, medical personnel, and healthcare
professionals. Each user wears a number of sensor
nodes that are strategically placed on her body. The
primary functions of these sensor nodes are to
unobtrusively sample vital signs and transfer the
relevant data to a personal server through wireless
personal network implemented using ZigBee
(802.15.4) or Bluetooth (802.15.1). The personal
server, implemented on a personal digital assistant
(PDA), cell phone, or home personal computer, sets
up and controls the WBAN, provides graphical or
audio interface to the user, and transfers the
information about health status to the medical server
through the Internet or mobile telephone networks
(e.g.,GPRS, 3G). The medical server keeps electronic
medical records of registered users and provides
various services to the users, medical personnel, and
informal caregivers. It is the responsibility of the
medical server to authenticate users, accept health
monitoring session uploads, format and insert this
session data into corresponding medical records,
analyze the data patterns, recognize serious health
anomalies in order to contact emergency care givers,
and forward new instructions to the users, such as
physician prescribed exercises.

Data Monitoring
The medical server keeps electronic medical records
of registered users and provides various services to
the users, medical personnel, and informal caregivers.
It is the responsibility of the medical server to
authenticate users, accept health monitoring session
uploads, format and insert this session data into
corresponding medical records, analyze the data
patterns, recognize serious health anomalies in order
to contact emergency care givers, and forward new
instructions to the users, such as physician prescribed
exercises. The patient’s physician can access the data
from his/her office via the Internet and examine it to
ensure the patient is within expected health metrics
(heart rate, blood pressure, activity), ensure that the
patient is responding to a given treatment or that a
patient has been performing the given exercises. A
server agent may inspect the uploaded data and create
an alert in the case of a potential medical condition.
The large amount of data collected through these
services can also be utilized for knowledge discovery
through data mining. Integration of the collected data
into research databases
Biosensors
A biosensor is an analytical device for the detection
of an analyte that combines a biological component
with a physicochemical detector component. It
consists of 3 parts:
The sensitive biological element or biological
material (e.g.: tissue, microorganisms, receptors,
enzymes, antibodies etc.). The sensitive elements can
be created by biological engineering.
The transducer or the detector element (works in
physicochemical way, optical, piezoelectric, electro
chemical etc.) that transforms the signal resulting
from the interdiction of the analyte with the
biological element
Associate electronics or signal processors that are
primarily responsible for the display of the results in
a
and quantitative analysis of conditions and patterns
could prove invaluable to researchers trying to page link
symptoms and diagnoses with historical changes in
health status, physiological data, or other parameters
(e.g., gender, age, weight). In a similar way this
infrastructure could significantly contribute to
monitoring and studying of drug therapy effects. A
vital sign monitoring system is shown in figure 2.
user friendly way. This sometimes accounts for the
most expensive part of the sensor device.
Bioreporters
Bioreporters refer to intact, living microbial cells that
have been genetically engineered to produce a
measurable signal in response to a specific chemical
or physical agent in their environment (Figure 3).
Bioreporters contain two essential genetic elements, a promoter gene and a reporter gene. The promoter
gene is turned on (transcribed) when the target agent
is present in the cell’s environment. The promoter
gene in a normal bacterial cell is linked to other
genes that are then likewise transcribed and then
translated into proteins that help the cell in either
combating or adapting to the agent to which it has
been exposed. In the case of a bioreporter, these
genes, or portions thereof, have been removed and
replaced with a reporter gene. Consequently, turning
on the promoter gene now causes the reporter gene to
be turned on. Activation of the reporter gene leads to
production of reporter proteins that ultimately
generate some type of a detectable signal. Therefore,
the presence of a signal indicates that the bioreporter
has sensed a particular target agent in its
environment. The cell’s environment. The promoter
gene in a normal bacterial cell is linked to other
genes that are then likewise transcribed and then
translated into proteins that help the cell in either
combating or adapting to the agent to which it has
been exposed. In the case of a bioreporter, these
genes, or portions thereof, have been removed and
replaced with a reporter gene. Consequently, turning
on the promoter gene now causes the reporter gene to
be turned on. Activation of the reporter gene leads to
production of reporter proteins that ultimately
generate some type of a detectable signal. Therefore,
the presence of a signal indicates that the bioreporter
has sensed a particular target agent in its
environment.
Requirements
Widespread BASN adoption and diffusion will
depend on a host of factors that involve both
consumers and manufacturers.
User-oriented requirements include the following:
Value
Perceived value can depend on many factors, such as
assessment ability, but overall, the BASN must
improve its user’s quality of life.
Safety
Wearable and implanted sensors will need to be
biocompatible and unobtrusive to prevent harm to the
user safety critical applications must have fault-
tolerant operation.
Security
Unauthorized access or manipulation of system
function could have severe consequences. Security
measures such as user authentication will prevent
such consequences.
Privacy
BASNs will be entrusted with potentially sensitive
information about people. Protecting user privacy
will require both technical and nontechnical
solutions. BASN packaging will need to be
inconspicuous to avoid drawing attention to medical
conditions. Encryption will be necessary to protect
sensitive data, and encryption mechanisms will need
to be resource-aware.
Compatibility
BASN nodes need to interoperate with other BASN
nodes, existing inter-BASN networks, and even with
electronic health record systems. This will require
standardization of communication protocols and data
storage formats.
Ease of use
Wearable BASN nodes will need to be small,
unobtrusive, ergonomic, easy to put on, few in
number and even stylish.
Applications of WBAN
Current healthcare applications of wireless sensor
networks target heart problems, asthma, emergency
response, stress monitoring.
Cardiovascular diseases
Smart sensor nodes that can be installed on the
patient in an unobtrusive way can prevent a large
number of deaths caused by cardiovascular diseases.
The corresponding medical staff can do treatment
preparation in advance as they receive vital
information regarding heart rate and irregularities of
the heart while monitoring the health status of the
patient
Cancer detection
A sensor with the ability to detect nitric oxide
(emitted by cancer cells) can be placed in the suspect
locations. These sensors have the ability to
differentiate cancerous cells, between different types
of cells.
Alzheimer and depression
Wireless sensor network can help homebound and
elderly people who often feel lonely and depressed
by detecting any abnormal situation and alerting
neighbors, family or the nearest hospital
Glucose level monitoring
. A biosensor implanted in the patient could provide a
more consistent, accurate, and less invasive method by monitoring glucose levels, transmit the results to a
wireless PDA or a fixed terminal, and by injecting
insulin automatically when a threshold glucose level
is reached.
Asthma
A wireless sensor network can help those millions of
patients suffering from asthma by having sensor
nodes that can sense the allergic agents in the air and
report the status continuously to the physician and/or
to the patient himself.
Preventing medical accidents
Approximately 98’000 people die every year due to
medical accidents caused by human error. Sensor
Network can maintain a log of previous medical
accidents, and can notify the occurrence of the same
accident and thus can reduce many medical
accidents.
Epileptic Seizures Strike Early Warning
Strokes affect 700,000 people each year in the US
and about 275,000 die from stroke each year.
Wearable sensor system has the ability to monitor
home bounded people by measuring motor behavior
at home for longer time and can be used to predict
clinical scores
HipGuard System
HipGuard system is developed for patients who are
recovering from hip surgery. This system monitors
patient’s leg and hip position and rotation with
embedded wireless sensors. Alarm signals can be
sent to patient’s Wrist Unit if hip or leg positions or
rotations are false.
MobiHealth
MobiHealth aims to provide continuous monitoring
to patients outside the hospital environment [36].
MobiHealth targets, improving the quality of life of
patients by enabling new value added services in the
areas of disease prevention, disease diagnosis, and
remote assistance, physical state monitoring and even
in clinical research. Therefore, a patient who requires
monitoring for short or long periods of time doesn't
have to stay in hospital for monitoring. Figure 4
shows the typical structure of MobiHealth project.
UbiMon
UbiMon (Ubiquitous Monitoring Environment for
Wearable and Implantable Sensors) aims to provide a
continuous and unobtrusive monitoring system for
patient in order to capture transient events. This is
shown in figure 5.
Advantages of WBAN
The biosensor based approach to medical care makes
it more efficient by decreasing the response time, and
reducing the heterogeneousness of the application.
The following are some of the advantages of WBAN:
Small and Efficient
Wearable BASN nodes will be small, unobtrusive,
ergonomic, easy to put on, few in number stylish and
efficient.
Remote health monitoring
Since the proposed WBAN is connected to a medical
server through GPRS or positioned with the help of a
GSM network remote health monitoring is possible.
Low cost
Advances in wireless communication and micro-
electro-mechanical systems (MEMS) allow the
establishment of a large scale, low power, multi-
functional, and (ideally) low cost network
Easy to implement
Since we use a three layer architecture the
complexity involves in the implementation of the
proposed WBAN is comparatively very low when we
compared with other PAN (Personal Area Network).
Scope
The scope of this proposed technology is not confines
to provide efficient communication solution to health
care system but also to provide efficient solutions for
telemedicine, military interactive entertainment etc.Advanced Diagnosis
The WBAN allow the physicians to monitor the
health care of a patient in real time and this
advantage allows the physicians or the caregiver to
provide advance diagnosis.
Challenges
For quality life healthcare is always a big concern for
an individual. Generally, health monitoring is
performed on a periodic check basis, where the
patient must remember its symptoms; the doctor
performs some tests and plans a diagnostic, then
monitors patient progress along the treatment.
Challenges in healthcare application includes: low
power, limited computation, security and
interference, material constraints, robustness,
continuous operation, and regulatory requirements.
Power challenge
As most wireless networks based devices are battery
operated therefore, power challenge is present in
almost every area of application of wireless sensor
networks, but limitation of a smart sensor implanted
on a person still poses even further challenge. To deal
with these power issues the developers have to design
better scheduling algorithms and power management
schemes
Computation
Due to both limited power as well as memory,
computation should also be limited. Unlike
conventional wireless sensor network nodes,
biosensors do not have much that computational
power. A solution is that some sensors may have
varying capabilities that communicate with each
other and send out one collaborative data message.
Security and Interference
One of the very important issues that could be
consider, especially for medical systems is Security
and interference. It is critical and in the interest of the
individual, to keep this information from being
accessed by unauthorized entities. This is referred to
as Confidentiality, which can be achieved by
encrypting the data by a key during transmission
Material Constraints
A biosensor should be implanted within the human
body; therefore the shape, size, and materials might
be harmless to the body tissue. Also chemical
reactions with body tissue and the disposal of the
sensor are of extreme importance.
Continuous operation
Continuous operation must be ensured along the
lifecycle of a biosensor, as it is expected to operate
for days, sometimes weeks without operator
intervention.
Regulatory Requirements
Regulatory Requirements must always be met, there
must be some testimony that these devices will not
harm human body. Therefore, it is imperative to have
diligent oversight of these testing operations.
Robustness
Whenever the sensor devices are deployed in harsh or
hostile environments Robustness rates of device
failure becomes high. Protocol designs must therefore
have built-in mechanisms, that the failure of one node
should not cause the entire network to cease
operation. A possible solution is a distributed
network where each sensor node operates
autonomously though still cooperates when
necessary.
Future
These advances in diagnostics, medicine and therapy
can only become reality by bringing life sciences
research to the next level. Life sciences can benefit
from progress in nanoelectronics which is now
working at dimensions and with a precision equaling
those of biology. In future autonomous sensor nodes
can be used to create a body-area network that is
worn on the body and that monitors vital body
parameters in an unobtrusive way during daily life.
When alarming values are reached, a caregiver can be
contacted.
Modeling and visualization of WBAN is another
future application. Another future concept is
Immersive Visualization System. This allows the
system to present to the user a 3D virtual world
within which the user can move and interact with the
virtual objects.
Conclusion
This paper demonstrates the use of Wearable and
implantable Wireless Body Area Networks as a key
infrastructure enabling unobtrusive, constant, and
ambulatory health monitoring. This new technology
has potential to tender a wide range of assistance to
patients, medical personnel, and society through
continuous monitoring in the ambulatory
environment, early detection of abnormal conditions,
supervised. restoration, and potential knowledge
discovery through data mining of all gathered
information. This paper proves that wireless sensor
networks can be widely used in healthcare
applications. We believe that the role of wireless
sensor networks / Body sensor networks in medicine
can be further enlarged and we are expecting to have
a feasible and proactive prototype for wearable /
implantable WBAN system, which could improve the
quality of life.
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