Towards 4G User centric, user controlled services and context-aware applications From a user prospective Multiple Heterogeneous network operators part of Multiple user environments accessed using Multiple heterogeneous devices

1. Mobility Management Challenges andMobility Management Challenges and
Issues in 4G Heterogeneous NetworksIssues in 4G Heterogeneous Networks
ByBy
AJAL.A.JAJAL.A.J
Towards 4GTowards 4G
User centric, user controlled services
and
context-aware applications

2. Technologies
ChallengesChallenges
• Convergence/integration/inter-working of all
existing and emerging fixed and mobile
(wired and wireless) networks including
broadcast
• Simple to select and easy to use desired
services
• Universal and low cost terminals
IP
Technology
Agent
Technology
Reconfigurable
Technology

3. The
Internet
IP backbone
Billing
VHE
Signalling
Gateway
WAP Accounting
UMTS
Broadcast Networks
(DAB, DVB-T)
Satellite FES
GSM /
GPRS
Context-aware information
Centre
IP-based
micro-mobility Wireless
LANs
ISPSIP Proxy
Server
Inter-Working

4. Global coverage
National coverage
Local area coverage
Wireless LANs
DAB and DVB-T, DVB-S
2G, 3G and 4G Cellular
Personal area coverage
Hierarchical coverage layers for 4G
Satellite
Regional coverage
Wireless PANs
Vertical Handover
Horizontal Handover
IP-based backbone

5. Multi-Agency Seamless Mobility

6. The Future Home…
DSL/Cable
or MSOTelephone
Wireless
camera
Wireless
media
gateway
NAS for
MP3 & Video
Content
Integrated networks, content,
and entertainment systems
Managed Security
Managed Voice
Managed Wireless

8. Success Story @ Work – Madras
Pharma
T.Nagar
Sholinganallur
• Point to Point and Point to Multi Point
• Backhaul spanning to 12kms from T.Nagar (H.O) to
Sholinganallur (Factory)

9. Success Story @ Work – Residency Group
Hotels
-Enable Point – to – Point Connectivity ( 1KM )
- Centralized accounting and reservation system
- Hotspot Zones for wireless internet access

10. Main BuildingAnnexe
Usman Road
• Point – to – Point Connectivity ( 600 meters )
• Enabling centralized billing and accounting systems
Success Story @ Work – GRT
Thangamaligai

11. The complexity of the problem: user prospective
From a user prospective
Multiple Heterogeneous
network operators
part of
Multiple user environments
accessed using
Multiple heterogeneous devices
owned by
heterogeneous users

12. A Heterogeneous Network Architecture
UTRAN WLAN 4G RAN
PAN
Wireless
Access Network
Core NetworkFuture Internet
Intra-Cell PAN
Ad-hoc Network PAN PAN
PAN

13. Re-configurable Technology
What does Reconfiguration mean?
“Reconfiguration refers to the software
re-definition and/or adaptation of every
element within each layer of the
communication chain.”
Baseband
Processing
User
Data
A/D Converter
D/A Converter
RF
Front End

14. Re-configurable Technology
Benefits
• Users
• Operators
• Manufacturers
- Select network depending on service requirements and cost.
- Connect to any network – Worldwide roaming.
-Access to new services.
- Respond to variations in traffic demand (load balancing).
- Incorporate service enhancements and improvements.
- Correction of software bugs and upgrade of terminals.
- Rapid development of new personalised and customised services
- Single platform for all markets.
- Increased flexible and efficient production.

15. Re-configuration Procedures
Reconfiguration
Trigger
Mode
Identification
Mode
Negotiation
Software
Download
Mode Switch
Decision
Mode
Monitoring
Reconfigure
Terminal
Initiated by network
operator or user
Download software
modules that are
required for the target
What networks are
available?
What is the most suitable
network (based on QoS,
user preferences etc.)?
Decision on preferred mode

16. Aggressive frequency re-use ⇒
High spectrum efficiency ⇒
Increased co-channel interference
Downlink Switched Beam Antenna
SIGNAL
OUTPUT
INTERFERENCE
SIGNAL
SIGNAL
OUTPUT
BEAMFORMER
WEIGHTS
Uplink Adaptive Antenna
SIGNAL
INTERFERENCE
BEAMFORMER
BEAM
SELECT
Smart antennas provide substantial interference
suppression for enhanced performance
Smart Antennas for 4G
• Key enhancement technique to improve system capacity and user experience
• Leverage Smart Antennas currently in development/deployment for IS-136 & GSM

17. Path Loss and Fading Challenge
Delay
Spread
Rayleigh
Fading
Path
Loss
rapid fading of 20 to 30 dB
(power varies by 100 to 1000 times
in level at rates of about 100 times per second)
path loss up to
~ 150 dB
(that is a 1 followed
by 15 zeroes)
Reflected signals
arrive spread out
over 5 to 20
microsecond

18. 4G Cellular Interference
Challenge
0.001
0.01
0.1
1
-5 0 5 10 15 20 25
1|3 reuse
2|6 reuse
3|9 reuse
4|12 reuse
7/21 reuse
Signal to Interference ratio in dB
CumulativeProbability
Each base station is equipped
with three 120 degree directional
antennas to reduce interference
& improve capacity

19. MIMO Measured Channel Capacity
Potential Capacity Relative to a Single Antenna System
• Capacity increase close to 4 times that of a single antenna is possible
with 4 transmit and 4 receive antennas
• Capacity for pedestrians is similar to mobile users

20. Space-Time Coding

21. OFDM for 4G Wireless
~ 6 kHz
~ 800
tones
~ 5 MHz
• OFDM is being increasingly used in
high -speed information transmission
systems:
- European HDTV
- Digital Audio Broadcast (DAB)
- Digital Subscriber Loop (DSL)
- IEEE 802.11 Wireless LAN
5 MHz channels
~ 6 KHz tones
~ 13/26 MHz sample rate
2048 FFT size (160 usec OFDM blocks)
256/512 sample OFDM block guard time
QPSK & 16-QAM modulation adaptive modulation/coding
1 to 2 msec time-slots in 20 to 40 msec frames
Mobile OFDM parameters: ex.