Four major Release-13 projects have been approved now that Release-12 is coming to a conclusion. One of them is Full dimension MIMO. From the 3GPP website:
There was also an interesting post by Eiko Seidel in the 5G standards group:
The idea is to introduce carrier and UE specific tilt/beam forming with variable beam widths. Improved link budget and reduced intra- and inter-cell interference might translate into higher data rates or increased coverage at cell edge. This might go hand in hand with an extensive use of spatial multiplexing that might require enhancements to today’s MU-MIMO schemes. Furthermore in active antenna array systems (AAS) the power amplifiers become part of the antenna further improving the link budget due to the missing feeder loss. Besides a potentially simplified installation the use of many low power elements might also reduce the overall power consumption.
At higher frequencies the antenna elements can miniaturized and their number can be increased. In LTE this might be limited to 16, 32 or 64 elements while for 5G with higher frequency bands this might allow for “massive MIMO”.
WG: Primary RAN1 (RP-141644)
started 06/2014 (RAN#64), completion date 06/2015 (RAN#68)
work item might follow the study with target 12/2015 (RAN#70)
Samsung/NSN, all major vendors and operators
Based on RAN1 Rel.12 Study Item on 3D channel model (TR36.873)
Phase 1: antenna configurations and evaluation scenarios Rel.12 performance evaluation with 3D channel model
Phase 2: study and simulate FD-MIMO enhancement identify and evaluate techniques, analyze specification impact performance evaluation for 16, 32, 64 antenna elements enhancements for SU-/MU-MIMO (incl. higher dimension MU-MIMO) (keep the maximum number of layer per UE unchanged to 8)
An old presentation from Samsung is embedded below that will provide more insight into this technology: