LTA-Advanced related technologies

3GPP release 10 is to introduce some LTE-A features. LTE-A can archieve >1Gbps data rate by 4-by-4 MIMO, on ~70MHz system bandwidth.

The spectrum efficiency for LTE Rel-8 satisfies IMT-Advanced requirements in the downlink, however, in the uplink, SE needs to double to satisfy IMT-Advanced requirements.

LTE-A related Rel-10 work items:

• Carrier Aggregation (CA)
• Enhanced downlink multiple antenna transmission
• Uplink multiple antenna transmission
• Relay
• Enhanced ICIC for non-CA deployments of Heterogeneous networks (eICIC)

1) Carrier Aggregation (CA)
Entire system BW up to 100MHz, composed of component carriers
Each component carrier can be configured in a backward compatible way
Support both contiguous and non-contiguous spectrum


2) Enhanced downlink multiple antenna transmission
Up to 8 layers transmission, increased from 4 layers in Rel-8/9
Additional RS signal specified
MU-MIMO (max 4 layers, 2 per user)
Dynamic switching between SU and MU-MIMO


3) Uplink multiple antenna transmission
UL transmit diversity for PUCCH
SU-MIMO up to 4-streams

4) Relay
For places where wired backhaul is not avialable or very expensive
"type 1" - inband relay, RN (Relay Node) appears to be a Rel-8/9 eNB.
"type 1a" - outband relay, backhaul use a different frequency from access link

5) eICIC
For Micro-Pico scenario,
DL - No Problem for control channel, reuse Rel8/9 ICIC for data channel
UL - Reuse ICIC for data channel, reuse power control in Rel8/9

For Micro-Femto scenario,
Consider power control and time domain solution as baseline solutions.
At least one common TDD and FDD solution whenever possible