Wireless Body Area Networks Case Study

This examination is in the context of whether or they qual-ify for ULP operations or not, and what can be done to make them qualify for such. A taxonomy of WSNs applica-tions is shown in Fig. 6. In our opinion, applications of wire-less sensor networks can be broadly categorized into two groups, namely; bio-medical and non-biomedical applica-tions.
A. Wireless body area networks (WBANs)
Wireless body area networks (WBANs) is a wireless net-work which permits the full exploitation of wireless sensors and complementary technologies in health care system. They comprise of miniaturized intelligent devices attached on or surgically implanted in the body capable of establish communication link, to provide real-time feedback to medi-cal experts or
With WBANs, patients can be alerted via text message, alarm, and precautionary/curative treatment can be given automatically [46]. Other WBANs could be used in the treatment or monitoring of gastrointestinal tract [47], cancer detection and myocardial infarction [48], to monitor asth-ma, diabetics, heart attack [49]. As an example, a complete and flexible sensor network for electromamogram (EMG)-for monitoring and assessing electrical activity generated by skeletal muscles, electroencephalogram (EEG)-for detecting medical problems connected with electrical activity of the brain, and electrocardiogram (ECG)-for monitoring the op-erations of the heart, built on SoC which incorporated adap-tive power management technology such as the use of boost circuits, sub-threshold processing, less energy consuming transmitter and bio-signal front-ends, and body heat energy harvesting was developed in [49]. Recognizing that existing sensors are not stretchable, limiting their body sensing capa-bilities, Maiolo et al. [50] reported on the use of PVD-TrFE pressure sensor and strain-gauge sensor with high stretchabil-ity in a wearable wristband to monitor the heart rate and fine muscle movement of
User comfort should be of paramount importance. The sensors should consumes ultra-low power to prevent unnecessary battery replacement. Furthermore, as noted by researchers from Stanford Univer-sity [53], pressure sensor miniaturization results in less trau-ma for patient. They also observed that tethered and wired sensor solution are beset by constraint in frequency. Mean-while, requirements of desirable wireless contact lens include [54]: (a) maintain reliability despite several eye blinks (b) flexibility and stretchability to enhance comfort (c) optically transparent, so as not to obstruct vision, and the materials used and its constituents after mixing with eye physiological parameters like tear, and glucose must be harmless to the eye. Previously existing micro electromechanical systems (MEMS)-based IOP sensors based on capacitance meas-urement are opaque and rigid. Chen et al. [55] reported an intra-ocular eye pressure monitor implantable in the eye of a person having glaucoma. To power itself, the sensor scavenges solar energy that gets to the eye since the sensor consists of a sized solar cell. With 10 hours of indoor light or 1 ½ hours of daylight the sensor could achieve lifetime operation. The authors in [52] developed a lens with a frequency response of 8 kHz/mmHg capable of sensing corneal curvature deformation. Zeng et al. [56] pre-sented a graphene based lens,