An Analytical Model of InterChannel Interference in Bluetooth based Systems

1
ETS Ingeniería Informática. Universidad de
Sevilla. Avda. Reina Mercedes s/n. 41012 Sevilla
(SPAIN)
Smart Homes, Ambient Intelligence.
José Luis Sevillano Robotics and Computer
Technology for Rehabilitation Lab. e-mail
sevi_at_atc.us.es
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Index

• Ambient Intelligence (AmI)
• Key Requirements
• AmI and Assistive Technologies
• Smart Homes
• A Layered Architecture
• Three levels of interactions
• Design issues
• Conclusions

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Ambient Intelligence (AmI)

• AmI concept Integration of digital devices and
  networks into everyday environments.
• The AmI vision is user centered.
• The user is the single master device
• New constraints
• Limited physical and/or cognitive abilities
• Mobility restrictions
• User's attention

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Ambient IntelligenceKey Requirements
Context Awareness
Ubiquitous Access
Natural Interactions
Intelligence
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Ambient IntelligenceKey Requirements

• Ubiquitous Access
• Anytime, anywhere and from any device.
• Mobile users (not just mobile computing but
  actually on the move)
• Handheld/wearable devices
• Wireless connections
• Implicit interactions computers and connections
  are pushed into background.

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Ambient IntelligenceKey Requirements

• Context awareness
• Use of information to characterize the situation
  of an entity (person, place, object).
• Context is continuously changing.
• Several dimensions
• Location awareness. Adaptation to users changing
  geographical positions and location based
  services.
• Temporal awareness. Time schedule of events.
• Personal awareness. Dynamic adaptation to user's
  needs or preferences.
• Other dimensions Device (processing power,
  battery, etc.) or Physical environment (noise,
  bandwidth, etc.).

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Ambient IntelligenceKey Requirements

• Intelligence
• Adapts itself to the people.
• Learns from users behaviour.
• Infers in the presence of ambiguity.
• Reflection the system modifies itself by means
  of
• Inspection.
• Adaptation.

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Ambient IntelligenceKey Requirements

• Natural interactions
• Natural languages speech, gestures, etc.
• Services should be easy to find and use.
• Reduce learning effort.
• Design for All.
• Guarantee accessibility

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AmI and Assistive Technologies

• Ubiquitous access
• Access to services not restricted by the location
  of resources/users.
• Especially useful with people with mobility
  restrictions.
• key issue new applications should not introduce
  additional barriers.
• Beware of useless technology.
• Context awareness
• Location
• Useful in special situations (e.g. unfamiliar
  environments).
• Assisted navigation (e.g. semi-automatically
  guided wheelchairs).
• Care of people that may get lost.

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AmI and Assistive Technologies

• Personal Awareness adaptation to users
  needs/abilities
• E.g. propose alternative routes for wheelchair
  users in structured environments.
• Time Awareness
• E.g. time orientation for mental disabled people.
• Intelligence
• Learn from users behaviour
• E.g. infer voluntary movements from uncontrolled
  tremor.
• Natural interactions
• Accessible human-machine interfaces

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Smart Homes

• Domestic environments in which we are surrounded
  by interconnected technologies that are
  responsive to our presence and actions.
• Not just domotics (control of devices), but also
  AmI issues.
• Access to multimedia contents.
• Homes are not custom designed from the start to
  accommodate and integrate these technologies.
• Two main approaches
• appliance model (functions are incorporated into
  devices).
• utility model some of the "intelligence" resides
  in the network (e.g. Telephone system).

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A Layered Architecture

• Focusing on networking issues, we consider 3
  layers
• Internetworking Layer
• All lower level functions.
• Middleware Layer
• Provides applications with a higher level of
  abstraction using primitives of the Network
  Operating System.
• Hides the complexity introduced by distribution
• Heterogeneity, resource sharing, scalability,
  etc.
• Applications Layer

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A Layered Architecture Three levels of
interaction

• The systems to interconnect may be distributed
  themselves

Interfunctionality
Interoperability
Interconnectivity
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A Layered Architecture Design Issues

• Mobility.
• Scarce resources
• Bandwidth, Computational power, battery power,
  screen sizes, etc.
• Fault-tolerance
• Intermittent failures, reachability, etc
  Dynamic connections
• Heterogeneity.
• Risk islands of functionality
• Context awareness.
• Adapt to user's location, characteristics, etc.

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A Layered ArchitectureInterconnectivity common
channel

• Mobility
• Asynchronous communications.
• Client and server may not be connected at the
  same time.
• Heterogeneity
• Nomadic (vs. Ad-Hoc) System A backbone, fixed
  infrastructure plus a number of mobile devices
  connected through wireless links.
• The infrastructure maintains knowledge about
  device characteristics and manages coherent
  device interactions.
• All IP networks.
• Internet Successful in the interconnection of
  heterogeneous devices.
• Connectionless (vs. connection oriented) well
  suited for intermittent connections (asynchronous
  communications).
• Context awareness
• Sensing and collecting context information

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Smart Home Scenario
HOME
Residential Gateway
PAN
USER
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A Layered ArchitectureInteroperabilitySyntactic
interaction

• Mobility
• Addressing devices obtain an IP address.
• Heterogeneity
• Service discovery and description.
• Context awareness
• Abstract context representation.
• Services at this level are Operating System-like
  functions

Generic, common protocols
Also for multimedia content distribution
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A Layered ArchitectureInteroperabilitySyntactic
interaction

• If Nomadic systems are used at the
  Interconnectivity level, then the fixed
  infrastructure may support some Interoperability
  functions (utility model)
• E.g. A central unit (Residential Gateway) may
  gather and distribute some services.
• E.g. The context captured by the closest service
  access point/provider can approximate that of the
  client.
• Or instead a fully distributed solution is
  possible (appliance model)
• Devices advertise services (multicast).
• Some technologies are available at this level
  (Jini, UPnP).

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Example UPnP Protocol Stack
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A Layered ArchitectureInterfunctionalitySemanti
c interaction

• Mobility
• Ability of use new functions with little or no
  advance planning.
• Heterogeneity
• Compatible authentication authorization
  mechanisms.
• Mix services from incompatible techs.
• Distributed proxies (Virtual services).
• Centralized gateways (OSGi Open Systems Gateway
  Specification).
• Difficult to foresee potential uses (services
  that the device were not designed for).
• Can the application level see a single, unified,
  universal interface to the whole system?.

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Conclusions

• 4 Key Requirements for AmI
• Ubiquitous access
• Context awareness
• Intelligence
• Natural interactions
• A Layered Architecture for Smart Homes
• Three levels of interactions
• Interconnectivity
• Interoperability
• Interfunctionality
• Design issues Mobility, Heterogeneity and
  Context Awareness

Effects on Assistive Technologies