262001
Mobile & Wireless Networking
Lecture 1:
Introduction & Wireless Transmission (1/2)
[Schiller, Section 1 & Section 2.1 - 2.5]
Geert Heijenk
Mobile and Wireless Networking
2009 / 2010
Outline of Lecture 1
Introduction
About the course “Mobile & Wireless Networking”
History
Current Wireless Technologies
Important trends
Wireless Transmission (1/2)
Frequencies
Signals
Antennas
Signal Propagation
Multiplexing
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Mobile and Wireless Networking
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Mobile & Wireless Networking
Mobile
user can use network services while moving
Wireless
communications without using a wire
w.r.t. point of attachment to network
Usually user is moving with his/her networking device
directly between two user nodes, or
(often) between user node and access point connected to the fixed
(wired) network
Networking
roughly, all architectures, protocols, and algorithms at the
link layer (mostly medium access control, MAC)
network layer, and
transport layer
(we will briefly address physical layer as well)
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Mobile and Wireless Networking
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What is different in wireless networks?
Higher loss-rates
Restrictive spectrum regulations
Lower transmission rates
Higher delays, higher jitter
Lower security
Shared and unbound medium
Mobility
change of point of attachment to network
how to find a user / device
Limitations of access devices
battery power
data loss
cpu
user interface
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Mobile and Wireless Networking
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Course Outline (Mobile & Wireless Networking, MW&N)
Basic principles:
•
•
•
•
•
•
Physical layer: propagation, multiplexing, modulation, spread
spectrum, OFDM
MAC layer: hidden terminals, medium access, random access,
CDMA, Hybrid ARQ
Cellular concepts: cell layout, interference
Dealing with mobility: handover, mobility management
Ad-hoc networks: problems of ad-hoc routing
Transport layer: problems with TCP over wireless
Systems:
•
•
•
•
•
Cellular: UMTS, LTE
Wireless LAN: IEEE 802.11a/b/g/e/n
Low power / short range systems: Bluetooth, Zigbee
Mobile IP: + Hierarchical Mobile IP, Fast Handovers for Mobile IP
Ad-hoc routing: DSDV, DSR, AODV
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Mobile and Wireless Networking
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Positioning Mobile & Wireless Networking
Telematica
Systemen
&
Toepassingen
networking
overview
Mobile
&
Wireless
Networking (1)
focus on link- and
network layer
of m&w networks
Telematica
Netwerken
Mobile
&
Wireless
Networking (2)
advanced:
ad-hoc
networks
networking
in-depth
Mobile
Radio
Communications
focus on
physical layer
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Mobile and Wireless Networking
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Course organization
See: http://www.cs.utwente.nl/~heijenk/mwn/
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Mobile and Wireless Networking
2009 / 2010
Outline of Lecture 1
Introduction
About the course “Mobile & Wireless Networking”
History
Current Wireless Technologies
Important trends
Wireless Transmission (1/2)
Frequencies
Signals
Antennas
Signal Propagation
Multiplexing
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Mobile and Wireless Networking
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History of wireless communication
Many people in history used light for communication
Discovery of electromagnetic waves
1831 Faraday demonstrates electromagnetic induction
1864 J. Maxwell theory of electromagnetic fields, wave equations
1886 H. Hertz demonstration of the wave character
of electrical transmission
Hertz: "It's of no use whatsoever[...] this is just an experiment that proves Maestro Maxwell was right - we just
have these mysterious electromagnetic waves that we cannot see with the naked eye. But they are there.”
1895
1907
1915
1920
1928
1933
Guglielmo Marconi, first demonstration of wireless
telegraphy (long wave)
Commercial transatlantic connections
Wireless voice transmission New York - San Francisco
Marconi, discovery of short waves
many TV broadcast trials (across Atlantic, color TV, TV news)
Frequency modulation (E. H. Armstrong)
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Mobile and Wireless Networking
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History of wireless communication II
1956
1972
1979
1982
First mobile phone system in Sweden
B-Netz in Germany
NMT at 450MHz (Scandinavian countries)
Start of GSM-specification
» goal: pan-European digital mobile phone system with roaming
1992
1997
1998
1998
1999
Start of GSM
Wireless LAN - IEEE802.11
Specification of UMTS
(Universal Mobile Telecommunication System)
Iridium: portable satellite telephony
IEEE Standard 802.11b, 2.4 GHz, 11 Mbit/s
Bluetooth, 2.4 GHz, < 1 Mbit/s
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Mobile and Wireless Networking
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History of wireless communication III
2001
2002
2004
2009
2010
Start of 3G (Japan)
UMTS trials in Europe
Start of UMTS in Europe
IEEE 802.11g
mobile subscribers overtake fixed-line subscribers
worldwide
1 billion cellular subscribers
UMTS launch in Netherlands
IEEE 802.11n standard
(December) First LTE Network (Stockholm / Oslo)
?? billion cellular subscribers
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Mobile and Wireless Networking
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Wireless systems: overview of the development
cellular phones
1981:
NMT 450
satellites
1983:
AMPS
1986:
NMT 900
1992:
GSM
1994:
DCS 1800
analogue
1982:
Inmarsat-A
1991:
D-AMPS
1984:
CT1
1987:
CT1+
1989:
CT 2
1992:
Inmarsat-B
Inmarsat-M
1993:
PDC
1991:
DECT
1998:
Iridium
2000:
GPRS
199x:
proprietary
1997:
IEEE 802.11
1999:
802.11b, Bluetooth
2000:
IEEE 802.11a
2001:
IMT-2000
digital
4G – fourth generation: when and how?
wireless LAN
1980:
CT0
1988:
Inmarsat-C
1991:
CDMA
cordless
phones
200?:
Fourth Generation
(Internet based)
Mobile and Wireless Networking
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Current wireless technologies (1/2)
Telecommunication Systems
WLAN
initial / primary service: mobile voice telephony
large coverage per access point
(100s of meters - 10s of kilometers)
low - moderate data rate
(10s of kbit/s - Mbits/s)
Examples: GSM, UMTS, LTE
initial service: wireless ethernet extension
moderate coverage per access point
(10s of meters - 100s of meters)
moderate - high data rate
(Mbits/s - 10s of Mbits/s)
Examples: IEEE 802.11b, a, g, n.
Short-range
Other systems
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Mobile and Wireless Networking
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Current wireless technologies (2/2)
Short-range
direct connection between devices (< 10s of meters)
typical low power usage
examples: Bluetooth, IrDA, ZigBee
Other systems
Satellite systems
global coverage,
applications
– audio/TV broadcast; positioning
– personal communications
Broadcast systems
Fixed wireless access
several technologies (DECT, WLAN, IEEE802.16 (11-60GHz))
DECT
satellite/terrestrial
DVB, DAB (Support of high speeds for mobiles)
Digital Enhanced Cordless Telecommunication
TETRA
Terrestrial Trunked Radio
Netherlands: C2000 system
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Mobile and Wireless Networking
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Standardization
3GPP (3G partnership project) (UMTS, LTE)
3GPP2 (CDMA2000)
IEEE (Institute of Electrical and Electronics Engineers)
www.3gpp.org
specification downloadable (free of charge) from ftp://ftp.3gpp.org/
Specs/
802.11 (Wireless LAN: WiFi)
802.15 (Wireless PAN: Bluetooth, Zigbee)
802.16 (Broadband Wireless Access: WiMAX))
IETF (Internet Engineering Task Force)
Mobile IP
AODV
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Mobile and Wireless Networking
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Outline of Lecture 1
Introduction
About the course “Mobile & Wireless Networking”
History
Current Wireless Technologies
Important trends
Wireless Transmission (1/2)
Frequencies
Signals
Antennas
Signal Propagation
Multiplexing
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Mobile and Wireless Networking
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Mobile subscriptions
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Mobile and Wireless Networking
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Mobile subscriptions per region
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Mobile and Wireless Networking
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Trends in computing
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Mainframe (one computer, many people)
PC (one person, one computer)
Ubiquitous computing
(one person, many computers)
16
14
A proliferation of small, lowcost, embedded devices
incorporating computing and
communication capabilities
10
8
6
4
Moving towards pervasive
computing
Yr
2005
2000
1995
1990
1985
1980
1975
1970
1965
1960
1955
1950
0
1945
2
1940
Sales/Yr
12
Source: Presentation by Marc Weiser ”Nomadic issues
in Ubiquitous computing”, Xerox, Palo Alto. Research Center, 1996.
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Mobile and Wireless Networking
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Wireless and mobile systems evolution
Vehicle
Walk
Fixed
4G
Cellular
Short range
0,1
1
WLAN
10
100 Mbps
User Bitrate
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Mobile and Wireless Networking
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