Method for reception in cooperative transmission environment and terminal
One embodiment of the present specification provides a reception method for a terminal supporting cooperative multi-point (CoMP). The reception method for the terminal may comprise the steps of: receiving a signal which indicates that a channel state indicator-reference signal (CSI-RS) port and a cell-specific reference signal (CRS) port are almost quasi co-located; and determining a frequency offset between a CRS and a demodulation-reference signal (DM-RS), which is quasi co-located with the CRS, on the basis of the signal which indicates that the CSI-RS port and the CRS port are almost quasi co-located. Herein the frequency offset between the CRS and the DM-RS may be within 50 Hz.
1. A receiving method by a user equipment (UE) supporting CoMP (Cooperative Multi-Point), the receiving method comprising:
receiving a signal indicating that a channel state indicator-reference signal (CSI-RS) port and a cell-specific reference signal (CRS) port are quasi co-located; and
determining a frequency offset between the CRS and a quasi co-located demodulation-reference signal (DM-RS) based on the signal indicating that the CSI-RS port and the CRS port are quasi co-located, wherein the frequency offset between the CRS and the DM-RS is within 50 Hz,
wherein the determining step of the frequency offset includes:
determining whether the CRS and the quasi co-located DM-RS are received from the same transmission port (TP); and
unless receiving the same transmission point (TP), estimating a frequency offset between the CRS and the quasi co-located DM-RS.
2. The method of claim 1 , wherein the signal is a radio resource control (RRC) signal.
3. The method of claim 2 , wherein the RRC signal includes one or more of a cell ID for the quasi co-located CRS and information on the number of CRS ports.
4. The method of claim 1 , further comprising
compensating for the frequency offset using the CRS when the frequency offset between the CRS and the DM-RS is larger than 50 Hz.
5. The method of claim 1 , further comprising
demodulating a physical downlink shared channel (PDSCH) using the DM-RS to receive data.
6. A user equipment (UE) supporting CoMP (cooperative multi-point), the UE comprising:
a radio frequency (RF) unit receiving a signal indicating that a channel state indicator-reference signal (CSI-RS) port and a cell-specific reference signal (CRS) port are quasi co-located; and
a processor controlling the RF unit and determining a frequency offset between the CRS and a quasi co-located demodulation-reference signal (DM-RS) based on the signal indicating that the CSI-RS port and the CRS port are quasi co-located, wherein the frequency offset between the CRS and the DM-RS is within 50 Hz,
wherein the processor determining the frequency offset determines whether the CRS and the quasi co-located DM-RS are received from the same transmission port (TP), and unless receiving the same transmission point (TP), estimates a frequency offset between the CRS and the quasi co-located DM-RS.
7. The UE of claim 6 , wherein the signal is a radio resource control (RRC) signal.
8. The UE of claim 7 , wherein the RRC signal includes one or more of a cell ID for the quasi co-located CRS and information on the number of CRS ports.
9. The UE of claim 6 , wherein the processor compensates for the frequency offset using the CRS when the frequency offset between the CRS and the DM-RS is larger than 50 Hz.