Systems, methods, and devices for hybrid full-dimensional multiple-input multiple-output

1. A UE configured to:

receive a channel state information reference signal (CSI-RS) from an evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node B (eNB);

determine channel state information based on the CSI-RS and send the channel state information to the eNB, wherein the channel state information comprises a precoding matrix indicator corresponding to a first precoding matrix, wherein the first precoding matrix comprises a matrix used for closed-loop beamforming (P d ), and wherein P d comprises a first dimension corresponding to a number of antenna ports and a second dimension corresponding to a number of layers;

receive a UE specific reference (UE-RS) signal and a physical downlink shared channel (PDSCH) signal, wherein the UE specific reference signal is precoded with a second precoding matrix, wherein the second precoding matrix comprises a matrix used for open-loop beamforming (P c ), and wherein P c comprises a first dimension corresponding to a number of transmitting antennas and a second dimension corresponding to the number of antenna ports;

estimate a UE-RS effective channel comprising the second precoding matrix based on the UE-RS; and

decode data from the PDSCH signal based on the first precoding matrix and the UE-RS effective channel.

2. The UE of claim 1 , wherein decoding data from the PDSCH comprises decoding further based on a plurality of additional matrices comprising one or more of:

a channel matrix H;

a cyclic delay diversity matrix for each resource element D(i); and

a square matrix U.

3. The UE of claim 2 , wherein the decoding component is configured to decode the data communication based on an assumed effective channel of one or more of:

HP c P d ;

HP c D(i)UP d ; and

HP c P d D(i)U.

4. The UE of claim 1 , wherein estimating the effective channel comprises estimating a value for HP c .

5. The UE of claim 1 , wherein the UE-RS is further precoded with the second precoding matrix and wherein estimating the effective channel comprises estimating a value for HP c P d .

6. The UE of claim 1 , wherein the CSI-RS comprises a first CSI-RS, the UE-RS comprises a first UE-RS, the PDSCH signal comprises a first PDSCH signal, and the first precoding matrix comprises a first precoding matrix corresponding to the first UE-RS, wherein the UE is further configured to:

determine second channel state information based on one or more second CSI-RS and send the second channel state information to the eNB, wherein the second channel state information comprises one or more second precoding matrix indicators corresponding to one or more second precoding matrices corresponding to the one or more CSI-RS;

receive one or more second UE-RS and one or more second PDSCH signals;

measure one or more second UE-RS effective channels for the one or more the second UE-RS; and

decode data from the one or more second PDSCH signals based on the one or more second UE-RS effective channels and the one or more second precoding matrices.

7. The UE of claim 1 , wherein the UE is further configured to measure a CSI-RS effective channel between the UE and the eNB based on the CSI-RS received from the eNB, wherein the CSI-RS comprises a CSI-RS precoded with the second precoding matrix.