Data transmission method and apparatus

1. A method of a user equipment (UE), the method comprising:

receiving configuration information related to a channel state information (CSI) process; and

measuring a channel state based on the configuration information,

wherein the CSI process is associated with at least two non-zero power (NZP) channel state information reference signal (CSI-RS) resources,

wherein the UE determines reference physical downlink shared channel (PDSCH) transmitted power corresponding to different NZP CSI-RS resources via higher layer signaling when measuring channel states in the CSI based on the at least two NZP CSI-RS resources, and

wherein the reference PDSCH transmitted power is determined based on an assumption P c of the reference PDSCH transmitted power corresponding to each NZP CSI-RS resource.

2. The method of claim 1 , further comprising:

measuring interference based on one zero power (ZP) CSI interference measurement (CSI-IM) resource.

3. The method of claim 1 , further comprising:

receiving scheduling information from the base station; and

receiving downlink data based on the scheduling information.

4. The method of claim 3 , wherein:

the scheduling information comprises information of de-modulation reference signal (DMRS) ports allocated to the UE, a number of data transmission layers and a number of resource element (RE) collections actually occupied by a DMRS N DMRS ,

the UE receives DMRSs based on the allocated DMRS ports and the number of data transmission layers,

DMRS ports 7 - 10 are used for supporting multi-user multiple input multiple output (MU-MIMO) transmission of the DMRSs, and

the UE receives a PDSCH from the RE collection of port 9 when the N DMRS indicates the DMRSs are transmitted using the RE collection of port 7 .

5. The method of claim 3 , further comprising:

increasing a length of a time-expanded Walsh code to support multi-user multiple input multiple output (MU-MIMO) transmission of de-modulation reference signals (DMRSs) signals, DMRS ports having best orthogonality among all of DMRS ports that support MU-MIMO are allocated to different layers of a UE or to different UEs,

wherein the scheduling information comprises information of DMRS ports allocated to the UE and the number of data transmission layers.

6. The method of claim 1 , wherein measuring the channel state comprises:

measuring channel characteristics of a two-dimensional antenna array on an axis x and an axis y respectively,

wherein the x and the y are directions respectively corresponding to two dimensions of the two-dimensional antenna array.

7. The method of claim 6 , wherein receiving the configuration information comprises:

receiving CSI-RS signals via NZP CSI-RS ports on which channel characteristics on the axis x and the axis y are measured,

wherein an NZP CSI-RS signal for measuring the channel characteristics on the axis x and the axis y is received from one NZP CSI-RS port for a shared antenna unit on the axis x and the axis y, and an NZP CSI-RS signal for measuring channel characteristics of another antenna unit is received from the other NZP CSI-RS port for the shared antenna unit.

8. The method of claim 6 , wherein antenna units in a cross-polarized two-dimensional antenna array are divided into two groups according to polarization directions,

wherein the configuration information of the at least two NZP CSI-RS resources comprises configuration information of NZP CSI-RS ports corresponding to each group of antenna units having the same polarization direction, and

wherein the two groups of antenna units are configured with the same number of NZP CSI-RS ports.

9. The method of claim 1 , further comprising:

reporting a pre-coding matrix indicator (PMI) and information of a phase between each pair of PMIs.

10. The method of claim 1 , wherein the configuration information comprises configuration information of N NZP CSI-RS resources, the higher layer signaling comprises the assumption P c of the reference PDSCH transmitted power corresponding to each NZP CSI-RS resource,

wherein the assumption P c corresponds to an index k, k is the index of each NZP CSI-RS configuration, k=0, 1, . . . N−1, and N is an integer larger than 2,

wherein the UE determines reference PDSCH transmitted power corresponding to different NZP CSI-RS resources, and

wherein the UE determines the reference PDSCH transmitted power based on P c when measuring CSI based on the k th NZP CSI-RS resource.

11. The method of claim 1 , wherein the configuration information comprises configuration information of N NZP CSI-RS resources, the higher layer signaling comprises the assumption P c of the reference PDSCH transmitted power configured for all of the N NZP CSI-RS, the UE determines the reference PDSCH transmitted power corresponding to the N NZP CSI-RS resources based on the assumption P c in the higher layer signaling.

12. The method of claim 1 , wherein the UE calculates the reference PDSCH transmitted power corresponding to a portion of the NZP CSI-RS resources based on a pre-set assumption of the reference PDSCH transmitted power, and

wherein channel status is measured based on a portion of the NZP CSI-RS resources without using an assumption of reference transmission power.

13. A user equipment (UE) for data processing, the UE comprising:

a configuration signaling receiving module configured to receive configuration information related to a channel state information (CSI) process from a base station (BS); and

a CSI measuring and reporting module configured to measure a channel state based on the configuration information,

wherein the CSI process is associated with at least two non-zero power (NZP) channel state information reference signal (CSI-RS) resources,

wherein the UE determines reference physical downlink shared channel (PDSCH) transmitted power corresponding to different NZP CSI-RS resources via higher layer signaling when measuring channel states in the CSI based on the at least two NZP CSI-RS resources, and

wherein the reference PDSCH transmitted power is determined based on an assumption P c of the reference PDSCH transmitted power corresponding to each NZP CSI-RS resource.

14. The UE of claim 13 , wherein the UE measures interference based on one zero power (ZP) CSI interference measurement (CSI-IM) resource.

15. The UE of claim 13 , further comprising:

a scheduling signaling receiving module configured to receive scheduling information from the base station, receives downlink data based on the scheduling information.

16. The UE of claim 15 , wherein the scheduling information comprises information of DMRS ports allocated to the UE, the number of data transmission layers, and

wherein the UE increases the length of a time-expanded Walsh code to support MU-MIMO transmission of DMRS signals, DMRS ports having best orthogonality among all of DMRS ports that support MU-MIMO are allocated to different layers of the UE or to different UEs.

17. The UE of claim 13 , wherein the configuration information comprises configuration information of N NZP CSI-RS resources, the higher layer signaling comprises the assumption P c of the reference PDSCH transmitted power corresponding to each NZP CSI-RS resource,

wherein the assumption P c corresponds to an index k, k is the index of each NZP CSI-RS configuration, k=0, 1, . . . N−1, and N is an integer larger than 2,

wherein the UE determines reference PDSCH transmitted power corresponding to different NZP CSI-RS resources, and

wherein the UE determines the reference PDSCH transmitted power based on P c when measuring CSI based on the k th NZP CSI-RS resource.

18. The UE of claim 13 , wherein the configuration information comprises configuration information of N NZP CSI-RS resources, the higher layer signaling comprises the assumption P c of the reference PDSCH transmitted power configured for all the N NZP CSI-RS, the UE determines the reference PDSCH transmitted power corresponding to the N NZP CSI-RS resources based on the assumption P c in the higher layer signaling.