Recent advances in low-power wireless communication
technologies like Zigbee (IEEE 802.15.4) [3], low-power
Bluetooth [4], etc. have enabled the development of small,
body-wearable, wireless sensors network for patient
monitoring [10].
One such architecture [5] is shown in
Fig.2, wherein the body sensors are the Bio-Front End
devices (BFEs) and they enable monitoring of multiple
bio-parameters (such as ECG, Blood Pressure, etc.) of
multiple patients at a central location.
The signal Transmission Schematic is shown in Fig.3. There can be
multiple BFE devices connected to a patient for
monitoring multiple parameters.
Normally an aggregator (AGG) device worn by the patient performs the function of
receiving the wirelessly transmitted data and transmits the
aggregated data to a backend PC or server.
The AGG device can be a device like a Portable Digital Assistant
(PDA) or a scaled down version of that, without a Liquid
Crystal Display (LCD). The AGG and the BFE devices
form a localized WBSN, with each BFE device having a
unique device ID.
The network system is normally comprised of energy constrained sensor nodes.
Furthermore, communication interference between multi
mode nodes in such a dynamic system is also a challenge.
This limitation has led to the crucial need for energy and
mobility aware protocols to produce an efficient network.