Multi-RAT Heterogeneous Networks
Presenter: S. Vasudevan, Technical Manager, Advanced Technology Standards
2 | 12) CDG | Oct 2009 All Rights Reserved © Alcatel-Lucent 2009
What are Multi-RAT Heterogeneous Networks
Integrated Networks supporting a range of cell sizes and backhaul solutions that allow for seamless interworking between multiple radio access technologies and are operated using novel scalable self-organizing and self-optimizing techniques
• cell sizes include macro, micro, pico, and femto
• backhaul solutions include existing carrier-grade backhaul, commercial grade wired backhaul, DSL, Cable, in-band wireless backhaul, i.e. relays, and out-of-band wireless backhaul
• radio access technologies include 2G onwards + WiFi and other unlicensed technologies where coupled with LTE/LTE-A radio access networks
• self-organizing and self-optimizing techniques apply e2e and include those for RAN and CORE
Such networks allow for
• Seamless mobility
• Leveraging of Common Network Assets especially in the CORE
• Common architecture and infrastructure for service delivery across the entire network
• Unconstrained radio evolution to meet changing subscriber needs
A good example is CDMA networks evolving to LTE via eHRPD
3 | 12) CDG | Oct 2009 All Rights Reserved © Alcatel-Lucent 2009
eHRPD - Not Just a Bridge to LTE – Not just voice
Embrace the Web
Extend Communication Offers to PCs Bring IMS Services to Mobiles
Today – Voice Centric Svc
Applications Enablement: Enables 1xEV-DO to go beyond conversational services and offer converged multimedia, messaging & web services
4 | 12) CDG | Oct 2009 All Rights Reserved © Alcatel-Lucent 2009
LTE HotZone
Strategic LTE
In-bldg
Enabling Seamless Mobility - 1
CDMA/LTE Seamless Mobility will be critical for a successful LTE deployment
– LTE technology deployment will target high data traffic areas first
– Users will continue to demand uninterrupted coverage
– Interworking LTE with eHRPD (EV-DO) data and 1X voice maximizes ROI on all assets
eHRPD is required for seamless IP mobility between EV-DO and LTE:Standalone eHRPD enables mobile enterprise VPN services & “always on” user services in
advance of LTE migration
LTE Urban build-out
EV-DO UmbrellaNetwork
5 | 12) CDG | Oct 2009 All Rights Reserved © Alcatel-Lucent 2009
Enabling Seamless Mobility: Leveraging the LTE Air Interface for Hand-down to eHRPD
E-UTRAN broadcasts pre-registration zone indication and CDMA system timeAllows a UE to pre-register on HRPD and maintain the HRPD session via an inter-RAT tunnelSupports a UE in quickly acquiring the CDMA pilot and CDMA system timing
LTE HotZone
Strategic LTE
In-bldg
LTE Urban build-out
eHRPD UmbrellaNetwork
MMEeRNC
Pre-registration zone
6 | 12) CDG | Oct 2009 All Rights Reserved © Alcatel-Lucent 2009
Seamless Mobility: Pre-registration and Pre-registered Session Maintenance
Subnet 1 pre-
registion zone
Subnet 2
HRPD CoverageLTE Coverage
pre-registration zone. Pre-registration zone code =
HRPD color code
Pre-registration triggering
Boundaries
Subnet 1
Subnet 2 pre-
registion zone
A
B
C
D
A: Pre-registration to subnet 2
B: No activity.
C: Pre-registration to subnet 1. (Triggered session transfer from subnet 2 to subnet 1)
D: No activity.
A mobile travels along the
border area
The mobile’s pre-registration activities:
HRPD Subnet border era
identified by Secondary color codes
LTE/HRPD coverage boundary
7 | 12) CDG | Oct 2009 All Rights Reserved © Alcatel-Lucent 2009
Seamless Mobility: Idle Hand Up from eHRPD to LTE
Global HRPD Coverage
LTE + HRPD Overlapped Coverage
HRPD Coverage HoleLTE coverage only
LTE Coverage Border Indication Triggers LTE to
HRPD Re-selection
HRPD Coverage Border Indication enables HRPD to
LTE soft Re-direction
Spatial Hysteresis
LTE LTE + HRPD HRPD
HRPD Traffic
LTE Traffic
HRPD Traffic
HRPD TrafficLTE Traffic
HRPD to LTE reselection
triggering border
LTE to HRPD reselection
triggering border
8 | 12) CDG | Oct 2009 All Rights Reserved © Alcatel-Lucent 2009
High Level eHRPD Network
BTS
eRNC PDN-GWeHRPD
AT
HSGW
EAP AKA’
3GPP2 AAA
A10/A11 S2a
BTS
RNC HAPDSNA10/A11HRPD
AT
HRPD AT
HRPD
eHRPDInternetIntranet
IMS
3GPP AAA/HSS
STa
3GPP2 AAA
A12
A10/A11
9 | 12) CDG | Oct 2009 All Rights Reserved © Alcatel-Lucent 2009
1xEV-DO
(HRPD)
3GPP2
LTE
3GPP
IMSIMS
Core Network Integration: Hierarchical 1xEV-DO and A Flatter, All IP RAN and Core for LTE
eNode B
IP channel
Packet Switched Core
IP channel
PDSN
BSC / RNC
AAA
HSS/ SPRPCRF
Potential SW upgrade on
existing equipment
Legacy EV-DO AT
LTE AT
VPN
HA
Internet / IntranetInternet / Intranet
MME
SGW PDN
GW
eHRPD
eBTSeHRPD AT eRNC HS GW
BTS
Evolved Packet Core
10 | 12) CDG | Oct 2009 All Rights Reserved © Alcatel-Lucent 2009
1xEV-DO
(HRPD)
3GPP2
IMSIMS
Service Enablement: Integrating eHRPD RAN with Converged ServiceControl Core
Packet Switched Core
IP channel
PDSN
BSC / RNC
AAA
Potential SW upgrade on
existing equipment
Legacy EV-DO AT
VPN
HA
Internet / IntranetInternet / Intranet
eHRPD
eBTSeHRPD AT eRNC HS GW
BTS
HSS/SPR
SPR (Subscriber Profile Repository)• Pre-emption Priority• QoS Class identifiers• Guaranteed bandwidth (GBR) • Max Bit rates• Charging related information;• Subscriber category
PDN
GW
PCEF Policy & Charging Rules Function• Subscriber Identifier• IP address of the UE• IP-CAN bearer attributes• Request type (initial, modification, etc.)• Type of IP-CAN (e.g.HPRD, I-WLAN, etc.)• Location of the subscriber• PDN & PLMN ID• IP-CAN bearer establishment/modification
A policy management entity that provides dynamic control of QoS, gating & charging policies for the EPS bearers at the SDF level
• Determines how SDF’s should be treated by the PCEF (HS-GW & PDN-GW)
AF
OCS Online Charging SystemOFCS Offline Charging System
OFCSOCS
PCRF
AF (Application Function)• Subscriber Identifier• IP address of the UE• Media type and format• Flow description• Application identifier• Application Event Identifier• Priority • Emergency
11 | 12) CDG | Oct 2009 All Rights Reserved © Alcatel-Lucent 2009
Radio Evolution
Upgrade to HRPD Rev B while maintaining all IWK capabilities with LTE
Add software features from HRPD Rev C in a way that is transparent to the other radio accesses, for ex: to increase performance at cell edge
Multi-streaming is a promising technology with performance that can improve even further with interference cancellation enabled mobile receivers
Scheduler 1
RNC
Parse Incoming Data Stream for UserFlow Control based on Outflow
BS 1 BS 2
Scheduler 2Priority metric for
handoff users: each scheduler uses
combined throughput (at BS 1 + BS 2)
Throughput (sector 1) calculated from mobile feedback
Throughput (sector 2) calculated from mobile feedback