Special Feature: Advanced Hardware Technologies

Advanced Hardware Technologies for
Ubiquitous Services
Yuichi Kado†
Abstract
In the coming ubiquitous era, computing, sensing, and communication functions will be present justabout everywhere in everyday living space, and novel services that can help make our lives safer, more
comfortable, and more convenient are expected. This article describes the current state of research anddevelopment in advanced hardware technologies supporting human-centered services and discusses theoutlook for services based on these technologies.

1. Trends in ubiquitous services
Passive radio frequency identification (RF-ID) tags
and sensors are becoming progressively smaller,
cheaper, and better at network interfacing. They are
expected to be used in future ubiquitous services giving us safer, more comfortable, and more convenient
lives. Figure 1 shows domestic and overseas trends inubiquitous services. The vertical axis represents the† NTT Microsystem Integration Laboratories
Atsugi-shi, 243-0198 Japan
E-mail: kado@aecl.ntt.co.jp

Wide-area
networkLocal+remoteMainly local

degree of network usage (i.e., service area coverage)
and the horizontal axis represents the types of devices
used. First, there are services that target distribution
and goods management by attaching compact passive-type RF-ID tags without built-in batteries togoods and combining them with readers connected to
the network. In this way, a wide range of such services can be envisioned, from ones that are mainly
local in nature [1] to ones that make use of wide-area
networks [2]. There are also plans for testing theattachment of ultrasmall tags to admission tickets forevent management [3]. In addition to services using
RF-ID tags, there are services that use network-con-• Environment sensing• TrackWave
distribution
asset management• Emergency communication system• Baggage Direct(airport baggage management)• Electronic posters• Admission tickets(µ-chip)• Smart Shelf(electronic product shelves)
RF-ID tags/readers(goods management)• X10 wireless(home security, remote operation of home appliances)• Xanboo(home/store security management)• Webcam home surveillance• MOTE(compact wireless sensors
with communication function)• Screenfridge(passive RF-ID tags andhome network)

RF-ID tags/readers+ sensors (including cameras)(objects and environments
are sensing targets)• Aware Home
(Georgia Institute of Technology)• Smart Room (MIT)• Easy Living (Microsoft)
RF-ID tags/readers +compact sensors +home network(human-oriented context
awareness)

Fig. 1. Trends in ubiquitous services.

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for Ubiquitous Services

nected sensors. These range from wide-area services
such as environment sensing, information-collection
services in disaster areas, and emergency communication systems to remote services such as home andbusiness security management and home surveillance[4], [5]. Although these services are currently in thedevelopment stage, trials of a local service that links
RF-ID tags with a home network are under way.
Finally, while the targets of sensing in the above twotrends are mainly objects and environments, studies
have also begun on ways of making life more comfortable and convenient by facilitating interaction
between people and appliances or the environment.
This will be accomplished by embedding many compact sensors in everyday living spaces such as a homeso that the system is aware of people’s locations andcurrent circumstances [6], [7].
At present, the services mentioned above are either
at the business feasibility study stage or the R&D
stage. As sensors equipped with a short-range wireless communication function become smaller, consume less power, and cost less [8], we foresee the formation of flexible sensor networks in individual living spaces that will eventually be linked to form awide-area sensor network. It should then be possible
to provide many diverse services to users regardlessof their location.

2. Requirements of basic hardware technologies
Based on these trends in ubiquitous services, we
expect to see services expand their focus from goods
management to human centric needs. Figure 2
defines ubiquitous services as human-centered valueadded services and summarizes the requirements ofbasic technologies supporting these services. The
idea here is to construct an environment having closeknit interaction between individuals and the living
space through the use of densely arranged computing,sensing, and communication functions. In such anenvironment, the sensor-network system is aware of auser’s circumstances including physical conditionand of events and phenomena occurring nearby.
These capabilities make it possible to provide a user
with daily living support.
The key device in this environment is a sensor
equipped with a short-range wireless communication
function that can even be attached to people. Thissensor must have a compact, low-power configuration and an automatic calibration function and benearly maintenance-free. A user must also be able touse such a sensor by simply attaching it to an object
or his/her own body, and there must be almost no
maintenance required on the part of the user likechanging batteries. The operating system for the CPU(central processing unit) that controls sensors of thisUbiquitous services support a safe, comfortable, and convenient life, making it easy to access information(virtual world) from actual objects (real world) and by providing information processing functions.

By “information processing” we mean:• Converting accessed information to aform useful for people• Converting information to environment-control
parameters

Construct a human-sensitive environment having close-knit interaction
between individuals and the living space using densely arranged
computing, sensing, and communication functions.

Ubiquitous living space
ComputerComputer

Network

VirtualVirtualReal
Real

VirtualReal

By “easy” we mean:• Easy on people• No adverse effects on the human body
• No awkward feeling when wearing a device• Considerate of human sensitivities• Easy to use• Anyone can use • Obvious operation• Simple or zero maintenance

Computer
VirtualReal

Requirements of basic technologies• Sensors with a short-range wireless communication function(compact, low power, automatic calibration, maintenance-free)• Ubiquitous OS for controlling above sensors(real-time operation, dynamic adaptation function)• Sensor network(ad hoc capabilities, flexibility)• Portable gateway terminal from the sensor group to the public network(compact, light, low-power; personal authentication function)• Middleware(personal authentication function, agent function, customization function)

Fig. 2. Definition of ubiquitous services and requirements of basic technologies.

Vol. 2 No. 2 Feb. 200449

Special Feature

type must be capable of real-time operation and havea dynamic adaptation function.
A group of sensors forms an ad hoc sensor networkthat can pass sensing information to a broadband network via a portable gateway terminal while maintaining flexibility with respect to changing conditions.
This portable gateway terminal must have a compact,
light, and low-power configuration and a personalauthentication function. Furthermore, to simplify theuse of this system, the middleware used by the terminal must have an agent function and a customization
function.
3. Key hardware technologies
Let us now turn our attention to basic hardware
technologies, the key to ubiquitous services. With reference to Fig. 3, the main features of the technologies
that will be introduced in this special feature are as
follows. First, a group of sensors connected to a network by short-range wireless communications isessential for detecting and analyzing the location andstate of people and things in everyday living space. In
other words, sensors are indispensable devices forproviding an individual with sophisticated valueadded services.
The second article in this special feature describes
a compact wireless sensing device called a stick-on
communicator (StiC) that can be attached to all kindsof real-world objects including people, things, andenvironments. It enables object location and sensing
information to be output to a network. The system
obtains location information because the StiC has an
infrared light-emitter and its light is detected by an
infrared camera to extract location. This techniquemakes it possible to perform high-speed location
recognition at a rate of about 50 objects per second
including moving objects, which means that the location of about 100 objects within the camera’s field ofvision can be detected. Furthermore, with the aim of
combining this ubiquitous technology with broadband services, the system will incorporate a function
for embedding the sensing and location information
obtained in this way in real video images and delivering that video to remote locations.
Such a ubiquitous service will also need a device toprovide the user with audio and video information
based on the data obtained from the sensor group. To
this end, we are developing an ultrasmall audio
receiving unit called “Voice Ubique” that incorporates an ultrasmall speaker as an actuator (as opposed
to a sensor) and uses infrared radiation for shortrange wireless communications. This device is sosmall that it can provide information in the form ofaudio messages to the user’s ear without causing discomfort or any feeling of awkwardness even if it isworn all the time. VoiceUbique also has a built-in RFID tag so that value-added audio information specificRemote access of
personal information

Ubiquitous living space
Broadband
network

Ubiquitous information
management + inter-object
communication-control center
Sensor-group ad hoc
communication network
OS for sensor control
Short-range wireless communications• Faint radio signal• Infrared signal (IrDA)
Sensor• Detect location and state of things• Human-body sensing• Environment sensing

Actuator• Speaker• Vibrator• etc

Sensing information management• Privacy protection/control• Customization function

Security measures• Authentication device foraccessing personal information“Fingerprint
Verification device”“Voice Ubique”“Stick-on Communicator”“Odor sensor”

Fig. 3. Hardware technologies supporting ubiquitous services.

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Connection/linking with networks

Special Feature

Environment sensing
Living spacesensing

Advanced network sensing
Personal authentication

Atmospheresensing

Odor sensor
RF-ID tagPhysical-quantities sensors
Chemical-analysis sensors
Physical sensor
Chemical sensor

Fingerprint
verification device

Physical-quantities sensor system
Chemical sensor systemBall-type (diameter: 1 mm)
3D acceleration sensor
Compact,
integrated,
intelligent

Glucose/lactic-acidsimultaneous measuring device
Intelligent/integrated sensors• Semiconductor fine-processing technology• MEMS (Microelectromechanical system) technology• Biochemical sensor technology• Integration with semiconductor devices (signal-processing LSIs, etc.)

Fig. 4. Trends in sensing technologies.

to wearer can be provided. The third article describes
details of the device. To facilitate the creation ofvalue-added services, it will be necessary to obtainand analyze a large volume of information, including
personal information, and to provide the user withinformation timely in any connected environment.
Needless to say, it is vital that privacy be protected insuch a system. It is therefore essential to incorporate
network authentication for accessing personal information and personal authentication for the personusing the portable gateway terminal that transfers
information from the wearable sensor group to public
networks. The fourth article introduces a “fingerprint
verification device” for personal authentication thatanyone can operate.
The source of information for value-added services
is the vital signs of the person living at the place inquestion and environmental information from thatplace. The key device for obtaining this informationis the sensor. As shown in Fig. 4, sensors are becoming smaller, more integrated, and more intelligent
through the merger of microelectromechanical system (MEMS) and biochemical sensor technologies
based on semiconductor fine-processing technology
with analog-signal-processing LSI technology. In
addition, if we equip these devices with a wirelesscommunication function and connect and link themwith networks, it will be possible to perform
advanced real-time sensing while maintaining flexibility with respect to changing circumstances. In
other words, a sensor-network system will evolve to
become constantly aware of events and phenomena
occurring within the targeted living space.
At NTT Microsystem Integration Laboratories, weare researching and developing a number of advanced
Vol. 2 No. 2 Feb. 2004

sensing devices including the fingerprint verification
device, a glucose/lactic-acid simultaneous measuring
device integrating chemical sensors, and a bloodstream sensor that integrates optical devices. Given
the importance to one’s health of living in a comfortable and clean environment, the fifth article describes“odor sensor technology” that can perform highly
accurate analysis of trace substances in room air.
4. Outlook for ubiquitous services
Finally, let us discuss the outlook for ubiquitous
services and associated issues including the potential
for new forms of communication using ubiquitous
linking technologies.
The top half of Fig. 5 shows ubiquitous services
focused on managing goods. These types of services
are currently being studied for their business potential. In the future, we expect these services to expand
into human-centered value-added services and merge
with broadband businesses to provide new communication services that “transform the real world into
content”, as shown in the bottom half of the figure.
For example, we can envision the provision of animage-communication service that enables the user tointeract with remote people and things. In the initialstage of commercialization, as passive RF-ID tags
become smaller and cheaper, we expect ubiquitous
services to target needs like reducing distributionmanagement costs and improving the traceability offoodstuffs. Developing operations for managing suchinformation at a data center will also facilitate theprovision of sophisticated value-added services suchas health management and environment control for amore comfortable lifestyle.
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Special Feature

Services focused on goods management

Present

Household-goods management and home-security services using RF-ID tags
Machine-to-machine data-communication services distribution-management
centerADSL/ISDN
Human-centered value-added services

New communication services

Obtain real-world information in real timeusing sensor networks
Health-management and environmentcontrol services

Convergence of ubiquitous technologies and broadband businesses
Creation of new services that transform the real world into content

Image-communication services providing
interactivity with remote people and things

Vital-signs/environmental-information management center

Inter-object communication control center

FutureBroadband
networkFig. 5. Outlook for ubiquitous services.

We plan to continue researching and developing
advanced hardware technologies with an eye toproposing novel communication services based on
the convergence of ubiquitous technologies andbroadband enterprises.
References
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]

[9]

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http://www.y12.doe.gov/orsens/smrtshlf.
http://www.trackwave.com.sg/index.htm
http://www.rhc.renesas.com/business/package_rfid.html
http://www.x10.com/homepage.htm
http://www.xanboo.com/
http://research.microsoft.com/easyliving/
http://www.cc.gatech.edu/fce/ahri/
J. Terada, Y. Satoh, F. Morisawa, S. Mutoh, K. Fujii, and Y. Kado, “A
Wireless Sensor-Network System with a Dynamically Programmable
Sensor Interface,” Abstracts of IEEE Sensors, pp. 202-203, 2003.
Y. Kado, Y. Matsuya, and T. Tsukahara, “Low-power Circuit Technology toward Ultra-small Network Appliances,” NTT REVIEW,
Vol. 14, No. 5, pp. 49-55, 2002.

Yuichi Kado
Executive Manager, Smart Device Laboratory,
NTT Microsystem Integration Laboratories.
He received the M.E. and Ph. D. degrees inelectronics from Tohoku University, Sendai,
Miyagi in 1983 and 1998, respectively. In 1983,
he joined NTT Electrical Communications Laboratories, where he engaged in research on SOI
structure formation by heteroepitaxial growth.
From 1989 to 1998, he worked on the development of fully-depleted CMOS/SIMOX LSIs andultralow-power CMOS circuits. From 1999, heengaged in R&D on compact network appliances
using ultralow-power CMOS circuit technologies for ubiquitous communications. He hasserved as a program committee member of the
ISSCC (International Solid-State Circuits Conference) since 1999 and a technical committee
member of IEEE Computer Elements since 2003.
He is a member of IEEE and the Institute of Electronics, Information, and Communication Engineers of Japan.

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