Towards Safer Roads
New Frontiers for Wireless and Transport
Mahbub Hassan
PROFESSOR – Computer Science and Engineering
University of New South Wales, Sydney, Australia
Keynote Speech, 2011 Saudi International Conference on Information
Technology, Riyadh, 18-19 Sep
New Frontiers for Wireless Networking
From human consumers to real-time embedded systems
Embedded systems
need to be aware of
each others status
in real-time!
NOW
(already very challenging)
FUTURE
(even more challenging)
Vehicular Networking and Road Safety
A New Frontier for Transport

Wireless networking could
save many lives (1 million
people die each year from road
accidents)

Very attractive proposition
for Governments (new
spectrum already allocated)
Pump vehicular
data out 10 times
a second
Simple Idea, but Challenging to Realize
Too many cars, too many beacons on the air
We need smart beacon management
Reception
probability could
be as low as 30%
on a 8-lane road
INFOTAINMENT on the Road
New Market Opportunities
But high-speed
mobility poses new
challenges for
content delivery to
a vehicular user
This Presentation

Overview of Our Past Research



SAFETY as well as
INFOTAINMENT
Conclusion and Future Directions
Our research

SAFETY (Smart Beacon Management)




Smart repetition of beacons
Adaptive position update
Leveraging beacons to improve positioning accuracy
INFOTAINMENT


Intelligent streaming for high-speed mobility
Smart radio sharing between safety & infotainment
Smart Repetition
of safety beacons
Zhe Wang and Mahbub Hassan, “Blind XOR: Low-Overhead Loss Recovery for
Vehicular Safety Communications", IEEE Transactions on Vehicular Technology,
accepted with minor revision.
The Idea – Blind XOR


XOR multiple beacons from different vehicles into a single
one  recover more beacons per repetition
XOR without trying to learn receiver status via feedback (blind
XOR)  no feedback overhead
A
B
1
A
A⊕B
B
2
B
=
A ⊕ A⊕B
3
A
=
B ⊕ A⊕B
Reduces beacon failure probability by up to 60%
Adaptive Position Update
Quanjun Chen, Salil Kanhere, and Mahbub Hassan, “Adaptive Position Update for
Geographic Routing in Mobile Ad-hoc Networks", IEEE Transactions on Mobile
Computing, under minor revision.
The Idea and Results

Frequency of
beaconing is
adapted to the
location uncertainty
of a mobile node
Our Scheme
Cooperative Positioning
Jun Yao, Asghar Balaei, Mahbub Hassan, Nima Alam, Andrew Dempster “Improving
Cooperative Positioning for Vehicular Networks", IEEE Transactions on Vehicular
Technology, 60(6), July 2011.
The Idea of cooperative positioning


Reduce range information
exchange overhead via
network coding and other
protocol improvements
Reduction in load reduces
reception failure
probability, which
increases positioning
accuracy
PDR – packet delivery ratio
PAG – Positioning accuracy gain
Even under dense road traffic conditions, we achieve a 2-fold
reduction in beacon loss probability and 40% increase in positioning
accuracy
Content Streaming for Vehicular Mobility
Jun Yao, Salil Kanhere, and Mahbub Hassan, “Improving QoS in High-speed
Mobility Using Bandwidth Maps", IEEE Transactions on Mobile Computing, in
press (preprint - http://www.computer.org/portal/web/csdl/doi/10.1109/TMC.2011.97).
Available bandwidth is sensitive to road locations
31
19
Location = 500 meter road segments (Our Sydney 3G data)
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17
Content streaming to vehicular user
Geo-TFRC
TFRC
Makes use of bandwidth
knowledge per road segment
No bandwidth
knowledge
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18
Smart Switching between Safety &
Infotainment
Zhe Wang and Mahbub Hassan, “How Much of DSRC is Available for Non-safety
Use?", ACM VANET 2008 (in conjunction with MOBICOM 2008)
Zhe Wang and Mahbub Hassan, “Context-Aware Channel Coordination for DSRC”,
IEEE AUTONET 2008 (in conjunction with GLOBECOM 2008)
Use time and location contexts to switch DSRC between safety and
infotainment
We can achieve close
to theoretical optimum
capacity for
infotainment (based on
vehicle flow data for 5
locations in Sydney)
Conclusion (1)

Road Safety is very attractive for governments, but not much
of a ‘commercial driver’


May be slow to realize due to lack of govt. funding in some countries
Current communication-based road-safety models are
‘vehicle-centric’ (depends heavily on vehicle manufacturers and
specialized road-side units to communicate specifically with vehicles)
 Long penetration period (may be 15-20 years!)

May be we should investigate new communication models
with reduced or no dependence on vehicle hardware, no
requirement of specialized road side units, and comes with a
handy commercial driver of its own
Conclusion (2)

Contrary to safety, infotainment has a big business driver



By 2015, content streaming will constitute more than 50% of all mobile
data (market size - tens of billions of dollars)
Much of that streaming will be to moving vehicles
Infotainment does not have to rely on vehicle hardware, but would
benefit from better integration of ‘road knowledge’ to networking
protocols
Future Directions

SAFETY - Investigate new communication models



With reduced or no reliance on ‘vehicle hardware’
With good commercial driver
INFOTAINMENT

Better integration of ‘road knowledge’ to networking protocols
Back up slides
Measurement Architecture
Probe Server @ UNSW
Downlink Probe
(Packet Train)
Probe Trigger (every 200m)
Internet
Bandwidth is measured
every 200 meters of a road
Provider B
(HSDPA)
Provider A
(HSDPA)
Provider C
(pre-wimax)
Probe Client
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Measurement Hardware/Software

Off-the-shelf Hardware (Soekris)

Totally user-driven (no support from service provider)
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Routes Taken



•
Two routes (inbound: 7Km & outbound: 16.5Km)
Typical urban driving speed ~70-80Kmh
75 repeated trips spread over 8 months (Aug’07 – Apr’08)
Collectively 60 driving hours & 1600Km
outbound
inbound
UNSW
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