wilamowski-b-m-irwin-j-d-industrial-communication-systems-2011

Communications in Medical Applications 30-9
through multiple clothes. The architecture of the system comprises three sensor nodes that are placed
on the inner wear and connected to each other through digital yarn (having conductivity). The sensor
node signals are transmitted to the outer wear through the woven inductor channel, being supplied to
a personal sensor controller that stores and processes the received information. This approach presents
benefits as it reduces power consumption and enables over-the-air energy transmission, which allows
a dramatic increase in sensor network autonomy. The authors claim a sensor power consumption of
300.μW under a 3.3.V supply voltage (at 1.Mbps).
The MICS/WMTS-based BAN described by Yuce and Ho [32] is a three-tiered communication system
composed of sensor nodes, central control units (CCUs), a base station (composed of a CCU and
a PC), and a server. The lowest tier includes sensor nodes that collect and forward data from inpatients
(in bed) to a CCU using MICS technology. Then, the CCU conveys this data to the base station using
WMTS technology (second tier). The received data are then transmitted to an external server using the
internet (third tier). The MICS band is used for network communications at the sensor level due to its
low transmission power (25.μW) that enables high-sensor autonomy. Because the WMTS is allowed
to operate with higher power transmissions (10.dBm ≤ transmit power < 1.8.dB), it is often applied in
application scenarios where higher ranges are required (e.g., CCU communications). The authors claim
communications without significant delays.
30.5 automation
Automation has found application in a broad range of scenarios going from industrial plants
with assembly and transport robots, to smart homes adapted for patients with functional impairments,
to healthcare institutions employing medical robots in surgery or in patient rehabilitation.
Currently, it is playing an increasingly important role in healthcare systems as it improves
efficiency, increases the quality of service, saves time and manpower, and supports the execution
of dull (e.g., processing blood samples), dirty, or dangerous (e.g., handling chemical substances)
tasks. The following subsections introduce two representative healthcare domains where automation
is being effectively applied.
30.5.1 Smart Homes
The world population aged over 65 years is growing fast and it is expected to rise above 1490 million
people by the year 2050 [1]. Dishman [33] identifies four requirements that should be addressed to cope
with the current trends of elderly demographic increase: promote healthy behaviors, detect diseases
at an early stage, improve treatment compliance, and provide support for informal caregiving. These
requirements can be met by maintaining elderly (or impaired) people living in their homes [34], within
their social network, and being assisted by automation systems that, besides helping them with the
activities of daily living (ADLs), also monitor their health condition.
Smart homes can be defined as dwellings incorporating a communication network that connects
electrical appliances and services and allows them to be remotely controlled, monitored, and accessed [35].
Smart home communication requirements are significantly distinctive from those of technologies
addressing large buildings (e.g., BACnet, LON, and KNX/EIB) mainly in what concerns coverage area,
number of supported devices, and per module cost. As such, technologies like X10, Z-Wave, and ZigBee
were specifically developed targeting home networking.
X10 [36] is an open and an international standard protocol for home communications supporting
two physical media: the house electrical network and the radio frequency. The communication of data
employs brief radio frequency bursts (120.kHz signals) representing digital information, which are
inserted immediately after the mains 50.Hz sine wave origin. This protocol defines no specific medium
access mechanism, and to cope with high noise levels, a bit is always sent together with its complement,
resulting in a transmission rate of one data bit per cycle of the electricity network.
© 2011 by Taylor and Francis Group, LLC