Transcript Location Sensing (Inference) CS492B proposal 2005.11.3 이영기, 배진석

Location Sensing (Inference)
CS492B proposal
2005.11.3
이영기, 배진석
Contents
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Definition of location sensing
Motivation
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Location sensing system
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Ubiquitous computing
Location-based computing
Requirements
Possible technologies
Technology examples
Expected results and plans
Locating the exact position of moving objects (end
users, mobile devices)
Motivation
(Ubiquitous Computing)
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Ubiquitous applications
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Collect context or environmental information
Process the collected information
Deliver useful services
First step of most ubiquitous applications
is collecting context information
Location will be significant information
for future ubiquitous services
Motivation
(Location-aware Computing)
Indoor
802.11 WiFi
Moving
Objects
Location Data
Outdoor
CDMA
Location data filters
GPS. RFIDs, beacons
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Location-based services
The location is an important context that changes whenever the
object moves
Location-aware services allow to offer value-added service to th
e user, depending on their current geographic position and will b
e a key feature of many future mobile applications
Requirements of Location System
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Affordability
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Resource requirements
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Fast evolution of mobile devices
Precision
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Hide users’ location
Portability
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Limited memory, computational capabilities, and power
Privacy
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Client cost + infrastructure cost
Granularity that a system is capable of measuring
Accuracy
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Percentage of the time a known level of precision is
reached
Technologies
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Outdoor
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GPS, triangulation in cellular network
Indoor
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RFIDs
Ultra-wideband
802.11 timing
802.11 signal strength
Many low-power 802.11 access points
Many low-power Bluetooth sensors
Technologies: Wireless LAN
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Timing and signal strength
Technologies:
Ultrasonic pulses and radio signals
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Active Bat
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ultrasound time-of-flight
measurement
can locate Bats to within
9cm of their true position
for 95 percent of the
measurements
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Cricket
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Ultrasonic time-of-flight
and a radio frequency
control signal
Lateration and proximity
techniques
Decentralized scalability
Technologies: RFIDs
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LANDMARK and SpotOn
b
a
c
RF
Reader1
d
f
e
tracking
tag
Four
Nearest
g
h
i
k
l
RF
Reader2
g
Expected Results
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What to do
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Extensive survey
A Seminar and a survey paper
Additional Work
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Implement one of the location inference
system and demonstrate
New location sensing system design
Plans
Date
Category
Contents
11.4~11.10
Outdoor
sensing
GPS, cellular network (e.g.
E911/E112, Place Lab)
11.11~11.16
Indoor
sensing
active badge(AT&T), active bat
cricket(MIT)
11.17~11.23
Indoor
sensing
wireless LAN based technologies
11.24~11.30
Indoor
sensing
RF-based systems(RADAR,
Pinpoint, SpotOn, LANDMARK)
11.30~12.6
Commercial
systems
commercial systems, other stateof-the art technologies
12.7~
seminar, survey paper