Paul Dalsgaard

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FACEFuture Adaptive Communication Environment

• Paul Dalsgaard
• Center for PersonKommunikation
• Aalborg University

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Outline

• Motivation
• FACE target environments
• Potential use scenarios
• Key Research Issues
• short-range networks
• speech multimedia
• Cellular systems
• Adaptable multimodal applications

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Motivation
Present - access to services through
A variety of Wireless Networks
A variety of Interfaces

• Cellular Network
• Wireless Local Area Network
• Wireless Personal Area Network
• Home Network

• Keyboard
• Touch Pad
• Mouse
• Display

Future integrated access
Access Anytime and Anywhere Terminal Small
Wireless
What is the most user-friendly environment ?
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FACE Target Environment
Interfaces Conversational and user-friendly
Networks Anytime and Anywhere
Spoken Language Processing Technologies
Wireless Technologies
Integration
Future Adaptive Communication Environment
Target is to provide users (customers) with
access to available services anytime and
anywhere using conversational interfaces
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Potential User Scenarios
Cellular Core Network
Dialog Management
Speech Recognition Server
IP-based Core Network
TTS (Text-to-Speech) Server
Spoken Language Functionalities
WLAN AP
Potential applications

• Voice-Enabled interactions with peripherals
• and appliances
• Voice-Enabled information retrieval
• Interactive voice response, etc

AP Access Point BS Base Station
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Key Research Issues - short-range network
The role of short-range network

• Establish network among devices around the
  user and provide person-centered network
• Provide users with connection to other
  networks and access
• to diverse services

WLAN AP
WPAN
Efficient Ad Hoc connectivity
QoS Support
Inter-working and Co-existence of different
short-range networks
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Challenges in MAC protocol design
Efficient MAC (Medium Access Control) Protocol
Design in Ad Hoc networks
Control transmission of each terminal sharing the
same medium
Challenges

• QoS support
• - How is QoS achieved (in environment
  influenced by delay, delay jitter,
• etc) when completely distributed MAC protocol
  such as CSMA is used?
• - How to interact with routing protocols
  constrained by the demand of
• achieving (user) requested end-to-end QoS?
• Power-Efficiency
• - How to design power-efficient MAC protocol?
• Inter-working/Co-existence
• - How to reduce interference among different
• short-range networks by using
• MAC-level scheduling?

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Key research issues speech multimedia

• Distributed Speech Recognition
• DSR client-server architecture
• A typical DSR system consists of two functional
  parts
• a Front-End (Client) and a Back-End (Server)
• IP and mobile channel are error-prone
• gt I.e. transmission error protection is
  essential
• Aimed at dealing with the degradations of speech
  recognition over mobile channels
• Standard published by ETSI - February 2000

MFCC
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Network-based spoken language processing

• Speech interaction User-friendly

Client
Server
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Key research issues Cellular systems

• Development of emulator for UMTS network
  behaviour
• Investigating the performance of application
  layer protocols over
• a UMTS network
• Application data sent through emulator for
  modification similar
• to real UMTS network
• Evaluation and tests conducted in conjunction
  with DSR system

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UMTS emulator
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Speech results so far

• Frame-based error protection scheme
• is able to better maintain the recognition rates,
  compared to the ETSI-DSR frame-pair scheme
• at the cost of only a marginal increase in
  bit-rate, from 4,800 bits/s to 5,000 bits/s for
  which there is plenty of bandwidth available in
  GSM and higher bandwidth wireless channels
• A FER-based OOV detection
• has proven successful in maintaining a constant
  false rejection rate across a range of
  transmission error rates
• Further research
• The principle of exploiting information about the
  channel will be used to adapt dialogue, grammars
  and vocabularies
• gt self-adaptable and re-configurable spoken
  language system.

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Adaptable multimodal applications

• Exploiting information about the quality of
  transmission channel
• e.g. fading channels, overloading services,
  congested networks and degraded acoustic
  environments
• to adapt dialogues, applied grammars and
  vocabularies in DSR
• Such further research will enable
• Self-adaptability and graceful modification of
  the behaviour of a given dialogue application (as
  given by current quality of the channel)
• The end-user is offered a system that give
  optimal Perceived Quality of Service

? Equal to User-friendliness ?
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Thank you for your attention