Transcript Mobile Communications

Mobile Communications
Chapter 11 : Outlook
The future of mobile and wireless
networks – Is it 4G? All IP? Licensed?
Public? Private?
Mobile and wireless services –
Always Best Connected
UMTS, GSM
LAN
LAN, WLAN
16 Mbit/s
GSM 53 kbit/s
Bluetooth 500 kbit/s
115 kbit/s
100 Mbit/s,
WLAN
54 Mbit/s
UMTS
2 Mbit/s
GSM/EDGE 384 kbit/s,
WLAN 1 Mbit/s
GSM 115 kbit/s,
WLAN 11 Mbit/s
UMTS, GSM
384 kbit/s
Wireless systems: overview of the
development
cellular phones
satellites
1983:
AMPS
1982:
Inmarsat-A
1984:
CT1
1986:
NMT 900
1987:
CT1+
1988:
Inmarsat-C
1991:
CDMA
1991:
D-AMPS
1989:
CT 2
1992:
Inmarsat-B
Inmarsat-M
1993:
PDC
1994:
DCS 1800
analogue
wireless LAN
1980:
CT0
1981:
NMT 450
1992:
GSM
cordless
phones
1991:
DECT
1998:
Iridium
2000:
GPRS
1997:
IEEE 802.11
1999:
802.11b, Bluetooth
2000:
IEEE 802.11a
2001:
IMT-2000
digital
4G – fourth generation: when and how?
199x:
proprietary
200?:
Fourth Generation
(Internet based)
Overlay Networks - the global goal
integration of heterogeneous fixed and
mobile networks with varying
transmission characteristics
regional
vertical
handover
metropolitan area
campus-based
in-car,
in-house,
personal area
horizontal
handover
Wireless access technologies
DAB
100
50
5
EDGE
FDD
GSM, TETRA
relative speed [km/h]
250
physical/
economic border
UMTS
TDD
DECT
802.11b
802.11a/g/n
Bluetooth
0
Point-to-multipoint distribution systems
10 kbit/s
2 Mbit/s
20 Mbit/s
bandwidth
150 Mbit/s
Key features of future mobile and
wireless networks
•
Improved radio technology and antennas
– smart antennas, beam forming, multiple-input multiple-output (MIMO)
• space division multiplex to increase capacity, benefit from multipath
– software defined radios (SDR)
• use of different air interfaces, download new modulation/coding/...
• requires a lot of processing power (UMTS RF 10000 GIPS)
– dynamic spectrum allocation
• spectrum on demand results in higher overall capacity
•
Core network convergence
– IP-based, quality of service, mobile IP
•
Ad-hoc technologies
– spontaneous communication, power saving, redundancy
•
Simple and open service platform
– intelligence at the edge, not in the network (as with IN)
– more service providers, not network operators only
Long Term Evolution (LTE)
• Initiated in 2004, focus on enhancing the Universal Terrestrial Radio
Access (UTRA) and optimizing 3GPP’s radio access architecture.
• Targets: Downlink 100 Mbit/s, uplink 50 Mbit/s
• 2007: E UTRA progressed from the feasibility study stage to the first issue
of approved Technical Specifications
• 2008: stable for commercial implementation.
• Downlink: OFDM, QPSK, 16QAM, and 64QAM
• Uplink: SC-FDMA, BPSK, QPSK, 8PSK and 16QAM
• Channel bandwidths between 1.25 and 20 MHz
• 4 x Increased Spectral Efficiency, 10 x Users Per Cell (MIMO), reduced RTT
• FDD and TDD supported, co-existence with earlier 3GPP standards incl.
handover
• Core network: System Architecture Evolution (SAE), optimizing it for
packet mode and in particular for the IP-Multimedia Subsystem (IMS)
LTE advanced
• GSM – UMTS - LTE
– LTE advanced as candidate for IMT-advanced
•
•
•
•
Worldwide functionality & roaming
Compatibility of services
Interworking with other radio access systems
Enhanced peak data rates to support advanced services
and applications (100 Mbit/s for high and 1 Gbit/s for
low mobility)
• 3GPP will be contributing to the ITU-R towards the
development of IMT-Advanced via its proposal for LTEAdvanced.
Example IP-based 4G/Next G/…
network
SS7 signalling
server farm,
gateways, proxies
broadcast
PSTN, CS core
gateways
MSC
IP-based
core
SGSN
BSC
GSM
firewall, GGSN,
gateway
router
Internet
access
points
private
WPAN
RNC
UMTS
public
WLAN
private
WLAN
Potential problems
•
Quality of service
–
–
–
–
•
Today‘s Internet is best-effort
Integrated services did not work out
Differentiated services have to prove scalability and manageability
What about the simplicity of the Internet? DoS attacks on QoS?
Internet protocols are well known…
– …also to attackers, hackers, intruders
• security by obscurity does not really work, however, closed systems provide some protection
•
Reliability, maintenance
– Open question if Internet technology is really cheaper as soon as high reliability
(99.9999%) is required plus all features are integrated
•
Missing charging models
– Charging by technical parameters (volume, time) is not reasonable
– Pay-per-application may make much more sense
•
Killer application? There is no single killer application!
– Choice of services and (almost) seamless access to networks determine the success
Have fun with mobile
communications!
This is the end of the slide set – but there
is so much more to say about mobile
communications!
Thanks for following so far and enjoy
digging into the fascinating wireless and
mobile world!
Jochen Schiller, Berlin/Germany, 2009