 |
Ambient Intelligence is a vision where
environment becomes smart, friendly, context-aware and responsive
to any type of human needs. In this world, computing and networking
technology coexist with people in a ubiquitous and pervasive way.
In this world, numerous miniature and interconnected smart devices
create a new intelligence and interact with each other seamlessly.
Wireless Sensor Networks (WSNs) are one of the first real world
examples enabling that vision of Ambient Intelligence. Within a
WSN, sensory data originate from multiple sensors of different types
spread over potentially wide areas. Virtually any kind of physical
quantities such as temperature, voltage, pressure, acceleration,
ultrasound, gas flow, etc. can be acquired. |
| Likewise, actuators
can be used as a means to influence or control the environment.
For coordination and information exchanges, the various nodes
communicate over a wireless mesh network in a self-organized manner.
Originally motivated by military applications such as battlefield
surveillance, the applications of WSNs are many and varied. Industrial
and home automation benefit from the capability to wirelessly
monitor data that would be difficult or too expensive to monitor
using wired sensors. Likewise, health care or environmental control
applications take advantage of the miniaturization and self-organized
nature of WSNs.
The many potential applications recently motivated
major players of the semiconductor industry to invest in this
promising field. STMicroelectronics has been among the first companies
to enter the WSN market with the introduction of sensors, low-power
microcontrollers, wireless radio devices, etc., in its portfolio.
STMicroelectronics is a promoter of the ZigbeeTM alliance, an
industry consortium working on the definition of network, security
and application layers towards truly interoperable WSNs.
One major technical challenge of WSNs is to produce low-cost,
low-power and tiny sensor and actuator nodes. Research work is
thus needed and involves numerous fields such as Radio Frequency
communication, ad-hoc networks, low-power microcontrollers, transduction
principles, energy management, middleware, etc. Another key aspect
is the coexistence and interoperability of WSNs with existing
technologies such as the Internet, broadband wireless networks
or database management systems. Given this wide list of topics,
this issue of the ST Journal of Research includes several overview
papers that help the reader capture the most important challenges
as well as a selection of contributions covering specific design
topics. Eleven papers have been selected from worldwide recognized
experts and ST researchers in the field.
The first section of this special issue includes three tutorial
papers. A general introduction to the problems and challenges
of developing Wireless Sensor Network devices is given, in the
first paper by Chalard et al. from STMicroelectronics. A particular
emphasis on ad-hoc networking technologies is proposed in the
second paper by Blasi et al. from STMicroelectronics and Bononi
from Universita di Bologna. Sheets et al. from the Univeristy
of California, Berkeley and Cervini from STMicroelectronics describe
in the third paper the main technical challenges faced in the
PicoRadio Project carried out at the Berkeley Wireless Research
Center.
Four contributions describing the application-specific nature
of WSN optimization are included in the second part of the issue.
An indoor climate monitoring prototype developed by our STMicroelectronics
colleagues illustrate the challenges of integrating WSNs with
the Internet via gateway and database client-server tools. Thonet
and Bruel from Schneider Electric discuss the mass market adoption
of ZigbeeTM solutions in the segments of Building Automation,
Home control, Automated Meter Reading and Industrial Automation.
The third paper, authored by Yao from UCLA and Lorenzelli from
STMicroelectronics, introduces different techniques for source
and node localization. In the last paper of this section, Farella
et al. from University di Bologna and Urbino expose the reader
to the application of WSN and MEMS sensors in the context of body
area networks, more specifically posture and activity recognition.
As mentioned above, a WSN device is a complex integrated system
implementing a combination of functions such as communication,
security and signal or application processing. The last part of
the issue includes four papers dedicated to specific design experiences
carried out in those areas. Two papers explore the promising use
of low data rate UltraWideBand radio communications in the context
of WSN. Specifically, Flury et al. from EPFL analyze the impact
of impulsive interference on network throughput and energy consumption.
Di Benedetto et al. from University La Sapienza focus their work
on medium access control schemes proposed for the IEEE 802.15.4a
standard. In the third paper Necchi and Lavagno from Politecnico
di Torino together with Pandini and Vanzago from STMicroelectronics
present their work in trading off power consumption and die area
for the design of an asynchronous 8-bit processor. Finally, in
the last paper, performances of two Elliptic Curve Cryptography
coprocessors are explored by Bertoni from STMicroelectronics together
with Breveglieri and Venturi from Politecnico di Milano.
Wireless Sensor Networks have the potential to open a new era.
However, as illustrated by the broad range of topics covered by
this special issue, technical issues still exist in the production
of low-cost small devices operating for years in a self-organized
way and seamlessly integrated with Internet access and appropriate
human interfaces. We believe that only companies having the capability
to master this broad spectrum of activities and to succeed in
both “more Moore” and “more-than-Moore”
directions will provide winning solutions for Ambient Intelligence.
The Guest Editors would like to thank all the Authors as well
as all those involved in the review and editorial process, with
a special mention to Antoine Hue for his huge contribution.
|
