1. WF on DL LBT Scheme for DRS
3GPP TSG-RAN WG1 Meeting #81
Fukuoka, Japan, 25th-29th May 2015 AI
Document for: Decision
R1-15xxxx
WF on DL LBT Scheme for DRS
Huawei, HiSilicon, NEC

2. Proposal 1
LBT without random backoff is used for DL transmission burst containing DRS without PDSCH within the DMTC
A single CCA idle slot allows the start of the DRS transmission
Transmission of reservation signal between the CCA idle slot and the transmission of DRS is possible
Note: eNB may check multiple CCA slots before finding one idle slot
A defer period is included when applicable
Further discuss the length of the CCA slot, the length of the defer period, and the energy detection threshold, or their possible ranges
The ECCA counter used for LBT category 4 for the PDSCH is frozen during DL transmission burst containing DRS without PDSCH

3. Proposal 2 Agree on Alt2 for DRS transmissions:
Subject to LBT, allow the DRS to be transmitted in at least one of different time positions within the configured DMTC
More than one candidate time position can be configured within the configured DMTC