DL Signals to Support Mobility Sample Clauses

DL Signals to Support Mobility. In LTE, the UEs monitor the quality of the active connection using the C-RSs as well as the UE- specific RSs. These signals can be used for estimating e.g. the Channel Quality Indicator (CQI), the RSRP (Reference Signal Received Power) and RSRQ (Reference Signal Received Quality), see [3GPP14-36214] for more details. To measure the quality of neighboring cells, the C-RS are used. The UE-specific RSs signals may be embedded in the data for specific UEs and are often called DeModulation Reference Signals (DM-RSs). They were standardized in Release 8, but enhanced in Releases 9 and 10. Discovery reference signals (DRS) were introduced in Release- 12, allowing more efficient small cell on/off operation via configurable periodicity of DRS occasions. As said above, XXXXX-XX believes the major difference between 5G and LTE for mobility will be the lean design of the control signaling and the use of massive beam forming in some scenarios. As said earlier, the reason for the lean design of the control signaling such as the reference signals is to be more energy efficient than LTE and also future proofness requirements, see Section 4.2. This means that 5G probably will not have the same cell concept as LTE with a C-RS transmitted continuously (see Section 4.2). However, METIS-II still believes there will a mobility function similar to LTE regardless of the cell concept and DL reference signal design in 5G. Exactly how this should look like will be further investigated. The other aspect that affects the mobility is that massive beamforming may be crucial for 5G in some scenarios. In order to handle this issue, different aspects should be considered. A first aspect that needs to be studied is the design of reference signals for the beams and its configurations used for link quality monitoring (for the serving beam) and neighbor link measurements and UE reporting mechanisms. Differently from LTE, these reference signals need to be designed to possibly be beamformed in wide and/or narrow beams. Assuming a network based approach as a baseline (as in LTE) the UE should be capable to synchronize and detect this signal(s) from neighbor beams(s) and report some indication to the network (e.g. absolute or relative neighbor beam quality/measurements) in order to get some sort of mobility command from the serving beam to the UE so the UE can synchronize and access the target selected beam before the sudden SINR drop occurs. The delay of this kind of procedure should be studied ...