Method and apparatus for csi feedback in a mimo wireless communication system with elevation beamforming

Abstract

A method of operating a communication system is disclosed. The method includes transmitting a plurality of channel state information reference signal (CSI-RS) sub-resources and a plurality of mode configuration signals to a remote transceiver. The method further includes receiving channel state information (CSI) signals according to the mode configuration signals for the respective sub-resources.

What is claimed is: 
     
         1 . A method of operating a communication system, comprising the steps of:
 transmitting a plurality of channel state information reference signal (CSI-RS) sub-resources to a remote transceiver;   transmitting mode configuration signals to the remote transceiver; and   receiving channel state information (CSI) signals according to the mode configuration signals for the respective sub-resources.   
     
     
         2 . A method as in  claim 1 , wherein the CSI signals for different CSI-RS sub-resources are configured with different reporting priorities. 
     
     
         3 . A method as in  claim 1 , wherein the mode configuration signals are independent from each other. 
     
     
         4 . A method as in  claim 1 , wherein a CSI signal for a first CSI-RS sub-resource comprises at least one of a rank indicator (RI), a precoding matrix indicator (PMI), and a channel quality indicator (CQI), and wherein a CSI signal for a second CSI-RS sub-resource comprises at least one of a RI, a PMI, and a CQI. 
     
     
         5 . A method as in  claim 1 , wherein the CSI signals comprise a first CSI signal for a first bandwidth and a second CSI signal for a second bandwidth. 
     
     
         6 . A method as in  claim 1 , wherein the CSI signals comprise a first CSI signal having a first periodicity and a second CSI signal having a second periodicity. 
     
     
         7 . A method as in  claim 1 , wherein the CSI signals are received periodically in different subframes. 
     
     
         8 . A method as in  claim 1 , wherein the CSI signals are received aperiodically in response to an uplink (UL) grant. 
     
     
         9 . A method as in  claim 1 , wherein the CSI signals are received aperiodically in response to a trigger signal that requests one of no CSI report, a first CSI report, a second CSI report, and the first and the second CSI reports. 
     
     
         10 . A method of operating a communication system, comprising the steps of:
 receiving a plurality of channel state information reference signal (CSI-RS) sub-resources from a remote transceiver;   producing channel state information (CSI) signals in modes configured by radio resource control (RRC) signaling for the respective sub-resources; and   transmitting the respective CSI signals to the remote transceiver.   
     
     
         11 . A method as in  claim 10 , wherein the CSI signals for different CSI-RS sub-resources are configured with different reporting priorities. 
     
     
         12 . A method as in  claim 10 , wherein the mode configuration signals are independent from each other. 
     
     
         13 . A method as in  claim 10 , wherein a CSI signal for a first CSI-RS sub-resource comprises at least one of a rank indicator (RI), a precoding matrix indicator (PMI), and a channel quality indicator (CQI), and wherein a CSI signal for a second CSI-RS sub-resource comprises at least one of a RI, a PMI, and a CQI. 
     
     
         14 . A method as in  claim 10 , wherein the CSI signals comprise a first CSI signal for a first bandwidth and a second CSI signal for a second bandwidth. 
     
     
         15 . A method as in  claim 1 , wherein the CSI signals comprise a first CSI signal having a first periodicity and a second CSI signal having a second periodicity. 
     
     
         16 . A method as in  claim 10 , wherein the CSI signals are received periodically in different subframes. 
     
     
         17 . A method as in  claim 10 , wherein the CSI signals are received aperiodically in response to an uplink (UL) grant. 
     
     
         18 . A method as in  claim 10 , wherein the CSI signals are received aperiodically in response to a trigger signal that requests one of no CSI report, a first CSI report, a second CSI report, and the first and the second CSI reports. 
     
     
         19 . A base station, comprising:
 a processor; and   a transceiver coupled to the processor and arranged to transmit a plurality of channel state information reference signal (CSI-RS) sub-resources and a plurality of mode configuration signals to a remote transceiver, and receive respective independent channel state information (CSI) reports for the CSI-RS sub-resources according to the mode configuration signals.   
     
     
         20 . A base station as in  claim 19 , comprising a plurality of antenna panels controlled for respective azimuth and elevation beamforming.