C. Çeken
(AP). A SN is an embedded device that is capable of sensing biological signals such as; heart rate, blood pres-
sure, oxygen saturation levels, blood glucose, brain activity, etc. from human body and can send them to the AP
using its wireless interface. Well-known ZigBee protocol is employed in the WSN and this module is modeled
and simulated using OPNET Modeler Software for performance evaluation. CN structure has a BS and two
transceiver interfaces which are integrated into the nodes AP in WSN and Server in Data Center. CN employs
GSM/GPRS protocol so that the biological data sensed can be delivered to the Data Center (DC), and modeled
using OPNET Modeler as well.
The framework has also a MATLAB interface which is presently monitor the sensed data (later, it will be uti-
lized in potential upcoming studies). Finally, the web based monitoring interface developed is responsible for
revealing the sensed biological data clearly and storing it into the database. In order to test the framework, a case
study that includes sensing, transferring, storing and web based monitoring processes of ECG signal is also in-
troduced in the study.
The contributions of this study can be summarized as follows:
• A new healthcare information system framework has been designed and implemented using several compo-
nents and various tools.
• Even though building a healthcare information system is quite complicated, related research studies can eas-
ily be realized by means of the framework developed, which implies that lots of time can be saved from
creating an experimental environment.
• A new bridge node (AP) that receives the sensed data from SNs using ZigBee protocol and delivers to the
Server in DC using GSM/GPRS, is developed.
The remainder of the paper is organized as follows: In Section 2, a brief literature search is given related to
the study. Overall properties and the components of the framework introduced are presented in Section 3. Sec-
tion 4 presents a case study that includes sensing, transferring, storing and web based monitoring processes of
ECG signal using the framework developed. The paper is concluded with the last section providing summary
about the study with final remarks.
2. Related Works
Several studies related to healthcare information systems can be found in the literature. In [3] [4], the authors
design a test platform based on TTCN-3 standard for interoperability testing of healthcare applications. The ar-
ticle [5] introduces a new XML-aware compression technique for improving performance of healthcare infor-
mation systems. In the study, two XML-aware compressors compress patient messages transferred between Web
clients and servers. In order to manage complex medical data, a framework for interoperable healthcare infor-
mation systems is proposed in [6]. In [7], a Smart Healthcare Systems Framework is proposed for conceptualiz-
ing data-driven and mobile/cloud enabled smart healthcare systems. Another healthcare information system is
introduced in [8] that enables standardized exchange and homogeneous management of ECG formats.
3. Architecture of the Framework
The framework developed consists of several components such as; body area network or WSN, cellular net-
works (CN), MATLAB interfaces, a database structure, and a web based monitoring interface. Here in this sec-
tion, all of the framework modules that are outlined in Figure 4 will be explained.
3.1. Body Area Network
WSN technology can commonly be deployed in industrial, medical, military, and environmental areas, for mon-
itoring, tracking, data processing and decision making purposes. ZigBee is based on an IEEE 802.15 standard
and is a specification for a suite of high level communication protocols used to create wireless personal/body
area networks [9]. In the framework, SNs firstly senses the biological signal from the human body and then
transferred it to the AP using ZigBee protocol. SNs and AP are both modeled in OPNET Modeler Software that
is a powerful event-driven tool for modeling and simulating various electronic communications systems. The
Node Model of the SNs built in OPNET is illustrated in Figure 1.
Sink, SourceGenerator, Network, and DLL modules in the figure are programmed using Proto-C language.
Proto -C is a special language includes state machines, transitions between states and C/C++ language. In Sour-
ceGenerator module, for the case study presented in the next section, the ECG signal is read from the “ECG.txt”