1. Views for The LTE-Advanced Requirements
3GPP TSG RAN IMT Advanced Workshop REV
Shenzhen, China,
April 7 – 8, 2008
Views for The LTE-Advanced Requirements
Agenda Item: 2.2 Manufacturers views
Source: Nokia & Nokia Siemens Networks

2. Outline Requirements from ITU-R IMT-A process Mobile Internet Outlook
LTE-Advanced Optimization for Nomadic / Local Area
LTE-Advanced Requirements - Suggested Upgrades to
Conclusions

3. IMT-A Requirements: Requirements from ITU-R IMT-A process
Mobile Internet Outlook
LTE-Advanced Optimization for Nomadic / Local Area

4. Status on IMT-A: Outcome from ITU-R WG5D meeting in January
The technical minimum requirements to IMT-A are given in draft IMT.TECH from ITU-R WG5D #1 in January to be finalized in WG5D #2 in June
The following minimum requirements are defined (values still largely open):
Cell spectral efficiency
Peak data rate (=peak spectral efficiency)
Bandwidth
Cell edge user throughput
Latency
Mobility
Handover
VoIP capacity

5. Draft IMT-A Minimum Requirements Summary
Draft values
Comments
Cell spectral efficiency
Base coverage Urban
DL: [2.1] b / s / Hz /cell
UL: [1.5] /[1.2] b / s / Hz / cell
Downlink – 4x2,
Uplink – 2x4 / 1x4
Peak data rate (=peak spectral efficiency)
DL: [7/10] b / s / Hz
UL: [2.5/5] b / s / Hz
Downlink – 4x4,
Uplink – 2x4
Bandwidth
[20/40] MHz.
Extensions up to 100 MHz
Cell edge user throughput
DL: [0.06] b / s / Hz / user
UL: [0.03] b / s / Hz / user
Latency
[100 ms] Control plane
[10ms] User Plane
From idle to active state
One-way transit time
Mobility
Up to 350 km / h
Handover
Intra Frequency [25/30]ms
Inter Frequency [tbd]
VoIP capacity
[40] active users / MHz / cell
Maximum number of users per cell ?
Note: “Red” numbers in [ ] are draft number to be agreed in ITU-RWG5D #2 in June

6. Mobile Internet Outlook
Internet traffic volume is increasing exponentially – doubling approximately each 6-12 months
~ x increase in data volume can be expected within the next decade
Large fraction of Internet services will go mobile
Low flat-rate tariffs for mobile data services have just started the mobile data tornado
Cost per bit reduction must follow the trend in user traffic volume increase
Real user data rates
10-50 Mbps at “preferred” user locations (home, work, coffee shops, centers, airport, hotel)
1-10 Mbps everywhere else.
80-90% traffic volume generated in indoor and hot-spot Nomadic scenarios
One secure subscription / identification ({U}SIM)
Best connected everywhere
Subscription portability
Transparent mobile / nomadic connectivity (Wide Area / Local Area)
Local decentralized services: Local WEB cacheing, proxy and content servers to achieve low response time and minimize backhaul transmission
Location and context aware services

7. LTE-Advanced Optimization for Nomadic / Local Area
EUTRA/EUTRAN is close to fulfilling the minimum requirements for high mobility wide area coverage
Focus needed on improvements for nomadic and local area (LA) scenarios
Backwards compatible solutions may not seize all (local area) optimization opportunities and new deployment options, e.g.
Optimization of numerology for low mobility LA
Optimization of physical and data link layers for
High data rate
High spectral efficiency
Low mobility
Reduced network complexity for LA
Low number of users per cell (not VoIP optimization centric)
Support of uncoordinated LA eNB deployment
Support of flexible spectrum use and spectrum sharing
Support of relays

8. LTE-A Requirements
Suggested Upgrades to

9. 6. LTE-A Capability-Related Requirements
Peak Data Rate
IMT.TECH set requirements to minimum bandwidth and peak spectral efficiency.
We anticipate a research target of 1 Gbps for DL and 500 Mbps for UL in 100 MHz BW, but at this stage we do not suggest this stretching target as a system requirement.
Suggested requirements:
Peak spectral efficiency of 15 bits/s/Hz in DL and 7.5 bits/s/Hz in UL
Scalable bandwidth exceeding 20 MHz, potentially up to 100 MHz
Latency
C-plane Latency: 100 ms (Similar to )
U-Plane Latency: 5 ms (Similar to )
Supported number of users
C-plane Capacity: 400 users in active state (potentially less for LA) (Similar to )

10. 7. LTE-A System Performance Requirements
User throughput
IMT-A set minimum requirements to user throughput (in terms of spectral efficiency)
We anticipate significantly higher targets for UL and slightly higher for DL
Suggested requirements:
DL [tbd] bits/s/Hz (numbers from IMT.TECH can potentially be used)
UL [tbd] bits/s/Hz (numbers from IMT.TECH can potentially be used)
Spectrum efficiency
IMT-A set minimum requirements to spectrum efficiency
Mobility: Similar to
Coverage: Similar to with increased attention to improved indoor coverage solutions
Further Enhanced MBMS: Similar to
Network synchronization: Similar to Option of loose “air-interface” synchronisation

11. 8. LTE-A Deployment-Related Requirements
Deployment Scenarios
LTE-A should in general be considered to be a backwards compatible enhancement to E-UTRA / E-UTRAN
LTE-A Local Area solution should also be considered for standalone deployment, e.g. with no previous wide area E-UTRA / E-UTRAN, but with interworking with existing UTRAN and/or GERAN coverage
Spectrum flexibility
Scalable bandwidth exceeding 20MHz, potentially up to 100MHz
Channel bonding should be considered
Necessity of channel aggregation and possible target bands should be carefully evaluated
Solutions for both paired and unpaired operation
Spectrum deployment
Similar to
New IMT-A bands (total IMT bands)
The potential of flexible spectrum usage mechanisms to enable FSU within the same Radio Access Technology between operators
Co-existence and interworking with 3GPP RAT

12. 9. LTE-A Requirements for E-UTRAN Architecture and Migration
Similar to
Advanced E-UTRAN shall be backwards compatible with E-UTRA, potentially enhanced with new functionalities and architecture elements if justified by performance enhancements or cost reduction.
Increased focus on decentralized network architecture, especially for nomadic/local deployment solutions

13. 10. LTE-A Radio Resource Management Requirements
Enhanced support for end-to-end QoS
Requirements similar to
Efficient support for transmission of higher layers
Support of load sharing and policy management across different radio access technologies
Increased focus on advanced E-UTRAN Wide Area / Local Area deployment scenarios

14. 11. LTE-A Complexity Requirements
Complexity requirements for overall system
Requirements similar to
Simplified operability by introducing additional automated functionalities
Complexity requirements for UE
Avoid setting mandatory requirements to UE’s which are in practice optional to the E-UTRAN and not supported by the majority of E-UTRAN vendors

15. 12. LTE-A General requirements
Cost-related requirements
Requirements similar to
Advanced E-UTRA/E-E-UTRAN should have increased focus on cost reduction solutions
Backhaul cost reduction
Cost per bit reduction
OPEX and CAPEX reduction by automatic and autonomous network configuration and operation
Service-related requirements
Similar to
Increased focus on new service scenarios

16. Conclusions
LTE Advanced shall meet or exceed the IMT-Advanced minimum capabilities.
Requirements for LTE Advanced shall not be less than those contained in TR
Advanced E-UTRA / E-UTRAN shall be based on E-UTRA / E-UTRAN evolution.
Non-backwards compatible elements can be studied as part of LTE-A SI, but subject for evaluation in RAN level.
Main focus on Requirements:
Nomadic / Local Area deployment scenarios
Increased focus on cost reduction solutions
Peak spectral efficiency of 15 bps/Hz (DL) and 7.5 bps/Hz (UL)
Enhanced average cell capacity of [tbd] (DL) and [tbd] (UL)
Enhanced (cell edge) user throughput of [tbd] (DL) and [tbd] (UL)
Scalable bandwidth exceeding 20 MHz, potentially up to 100 MHz
Spectrum flexibility