Transcript Document

4G Network Architectures
Final report to survey
 System issues
 Selected concepts for 4G
 Self-organizing ,Ad-hoc network for 4G
林家彬
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“4G” Design
Challenges
Although 3G is an important first step, several
basic issues still need to be addressed for next
generation wireless systems:
Fast/reliable broadband radios (PHY/MAC) with QoS
~100 Kbps 1-10 Mbps with adaptivity, link reliability & Qos
Scalable system capacity for mass-market services
high service penetration implies ~Gbps/Sq-Km
Integration of multiple radio technologies into single IP network
unified mobility architecture
New networking modes, e.g. multicast, multihop & peer-topeer
...lower-cost infrastructure, networks that grow organically
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4G System Issues
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4G System Issues: Scaling of
Capacity
 The
grand vision of ubiquitous wireless
and pervasive computing leads to a
serious capacity problem.
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4G System Issues: Scaling of
Capacity (cont.)
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2G cellular:
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3G Cellular:
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avail BW ~ 5 Mhz, spectral eff ~ 0.2-0.3 bps/Hz
max capacity ~ 100 Kbps avg, 1 Mbps peak (with packet
MAC) per sq-Km
avail BW ~ 25 Mhz, spectral eff ~ 0.3-0.5 bps/Hz
max capacity ~ 1 Mbps avg, 10 Mbps peak (with packet MAC)
per sq-Km
Wireless LAN (802.11x, Hiperlan):
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avail BW ~ 100 Mhz, spectral eff ~ 0.2-0.3 bps/Hz
max capacity ~ 100 Mbps avg, 1 Gbps peak per sq-Km
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4G System Issues: Evolution of
Radio Speed vs. Moore’s Law
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4G systems can exploit Moore’s law advances in
radio speed, but need to work with shorter range...
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4G System Issues: Protocol
Evolution
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Selected Concepts for 4G
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Potential “4G” Network Ideas
A few techniques for achieving the 4G design goals
discussed earlier:
3G/WLAN Hot-Spots
Use of WLAN in hot-spots for lower system cost,
better end-user performance and more total capacity
Infostations
Use of “radio caches” for significant reduction in
average cost per bit, facilitating qualitatively new
mobile services
Self-organizing, ad-hoc wireless access networks
Ad-hoc wireless network protocols which support
multihop and peer-to-peer service models, particularly
for low-tier uses (in-home, sensors, etc.)
Content-based multicasting
...new network service paradigms for location- and
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person-aware information delivery to mobiles
Self-organizing, ad-hoc
networks for 4G
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4G Mobile Network features
 Some
desirable new features for 4G
networks are:
 Unified
IP-based protocol architecture with
support for multiple radios
 Multicasting, caching and security features, etc.
 Hierarchical support of high-tier (cellular), med
tier (WLAN) and low-tier (personal area, sensor
nets)
 Self-organizing, ad-hoc wireless discovery &
routing
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4G Mobile Networks: Hierarchy &
Self-Organization
 Hierarchical,
self-organizing network
concept currently under consideration,
based on:
3
service tiers (cellular, WLAN, personal area)
 BS’s, AP’s, FN’s (forwarding radio nodes),
user devices
 automatic discovery and power management
protocols
 hierarchical, ad-hoc multi-hop routing
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4G Mobile Networks: “network of
wireless networks”
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4G Mobile Networks: An Experimental
Testbed
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Compare 3G & 4G
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Comparison of 3G and 4G
3G:
--Back compatible to 2G.
--Circuit and packet switched networks.
--Combination of existing & evolved equipment.
--Data rate (up to 2Mbps).
4G:
--Extend 3G capacity.
--Entirely packet switched networks.
--All network elements are digital.
--Higher bandwidth (up to 100Mbps).
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The NEWS about 4G
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ASIA : South Korean is already arranging an auction of 4G wireless licenses
across wireless and broadband internet.
• Successful Demo of Beyond-3G Wireless IP
• NEC Europe Ltd announced the successful completion of the three-year
“Moby Dick Project”, aimed at developing a seamless converged mobile
network architecture based on Internet Protocol version 6 (IPv6).
• Life After 3G Wireless
• With 3G set for widespread launch in 2004 across Europe, operators are
already thinking about the post 3G world and what comes next.
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• First Step Towards Full Range of WiMax / 4G Applications
• This successful implementation of the OFDM waveform is the first step in
Military Technologies plan to implement the complete IEEE 802.16 family of
wireless data applications
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• 4G Wireless 10 Years Away
• 4G? Not in this decade. “I would recommend that the newspaper
community forget about 4G,” Dr Keiji Tachikawa, president and CEO
of NTT DoCoMo
• Basestation Architectures for 3G Wireless
• picoChip Designs Ltd announced the world's most powerful
processing device for wireless infrastructure.
• The New WiFi Gels With 4G
• more robust standard for high-speed broadband wireless
delivery to laptops and desktops will augment the
burgeoning WiFi market beginning in late 2004. The
position of the 802.16a standard today parallels that of
WLAN technology in the late 1990’s, when the market
finally grew as 802.11 price vs. performance gains
converted WLAN from a niche to mass market.
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