Management of mimo communication systems

Abstract

Apparatuses of a user equipment (UE), a cellular base station, and radio access network (RAN) nodes are disclosed. An apparatus of a wireless communication device includes circuitry configured to measure reference signals received from a plurality of antennas of an other wireless communication device, and circuitry configured to cause one or more antennas of the wireless communication device to transmit information regarding the received reference signals back to the other wireless communication device to enable the other wireless communication device to estimate a utility function for different transmit parameter sets.

1 . An apparatus of a wireless communication device, comprising:
 circuitry configured to measure reference signals received from a plurality of antennas of an other wireless communication device; and   circuitry configured to cause one or more antennas of the wireless communication device to transmit information regarding the received reference signals back to the other wireless communication device to enable the other wireless communication device to estimate a utility function for different transmit parameter sets.   
     
     
         2 . The apparatus of  claim 1 , wherein the circuitry configured to cause the one or more antennas of the wireless communication device to transmit the information regarding the received reference signals is further configured to perform some pre-processing of the reference signals to reduce processing at the other wireless communication device to estimate the utility function. 
     
     
         3 . The apparatus of  claim 1 , wherein the circuitry configured to cause the one or more antennas of the wireless communication device to transmit the information regarding the received reference signals is further configured to quantize the reference signals, and the information regarding the received reference signals comprises data indicating the quantized reference signals. 
     
     
         4 . The apparatus of  claim 1 , wherein the one or more antennas of the wireless communication device comprise multiple antennas and the circuitry configured to cause the one or more antennas of the wireless communication device to transmit the information regarding the received reference signals is further configured to fix a receive beamforming vector before the reference signals are received. 
     
     
         5 . The apparatus of  claim 1 , wherein the information regarding the received reference signals comprises the reference signals themselves that have not been quantized by the circuitry configured to cause the one or more antennas of the wireless communication device to transmit the information regarding the received reference signals. 
     
     
         6 . The apparatus of  claim 1 , wherein the circuitry configured to cause the one or more antennas of the wireless communication device to transmit the information regarding the received reference signals is further configured to generate other reference signals and control the the one or more antennas to transmit the other reference signals to the other wireless communication device to enable the other wireless communication device to measure the uplink channel. 
     
     
         7 . The apparatus of  claim 1 , wherein the circuitry configured to cause the one or more antennas of the wireless communication device to transmit the information regarding the received reference signals is further configured to determine whether a codebook used to generate the reference signals at the other wireless communication device should be updated, and control the radio frequency circuitry and the one or more antennas to indicate to the other wireless communication device that the codebook should be updated. 
     
     
         8 . The apparatus of  claim 1 , wherein the wireless communication device includes a user equipment (UE) and the other wireless communication device includes a cellular base station. 
     
     
         9 . The apparatus of  claim 1 , wherein the circuitry configured to measure the reference signals received from the plurality of antennas of the other wireless communication device comprises radio frequency circuitry. 
     
     
         10 . The apparatus of  claim 1 , wherein the circuitry configured to cause the one or more antennas of the wireless communication device to transmit the information regarding the received reference signals back to the other wireless communication device comprises processing circuitry. 
     
     
         11 . An apparatus of a cellular base station, comprising:
 a data storage device configured to store data corresponding to a first codebook and a second codebook, the first codebook different from the second codebook; and   one or more processors configured to:
 precode reference signals to be transmitted to a user equipment (UE); and 
 precode, using the second codebook, data streams on a common resource element to prevent the data streams from interfering with each other. 
   
     
     
         12 . The apparatus of  claim 11 , wherein one or more of the first codebook or the second codebook is updated or replaced with a different codebook responsive to:
 a determination that a wireless propagation environment between the cellular base station and the UE has changed; or   an indication by the UE that the wireless propagation environment has changed.   
     
     
         13 . An apparatus of a Radio Access Network (RAN) node, comprising:
 a data storage device configured to store data corresponding to feedback information received from a UE; and   processing circuitry configured to:
 estimate a utility function for different transmit parameter sets based on the feedback information received from the UE; and 
 generate reference signals to be transmitted to the UE, the feedback information indicating information regarding measured signals measured by the UE responsive to transmission of the reference signals to the UE. 
   
     
     
         14 . The apparatus of  claim 13 , wherein the processing circuitry is configured to use a first codebook to precode the reference signals and a second codebook to precode data streams to be transmitted to the UE. 
     
     
         15 . The apparatus of  claim 14 , wherein the first codebook is the same as the second codebook. 
     
     
         16 . The apparatus of  claim 13 , wherein the processing circuitry is configured to optimize the estimated utility function for the different transmit parameter sets. 
     
     
         17 . The apparatus of  claim 13 , wherein the processing circuitry is configured to take into consideration statistical information about a wireless channel to estimate the utility function. 
     
     
         18 . An apparatus of a user equipment (UE), comprising:
 a data storage device configured to store a first beamforming codebook and a second beamforming codebook that is different from the first beamforming codebook; and   processing circuitry configured to:
 use the first beamforming codebook to reduce or compress dimensions of a receive beam space of a plurality of antennas of the UE; and 
 use the second beamforming codebook to filter data bearing signals received from a cellular base station. 
   
     
     
         19 . The apparatus of  claim 18 , wherein the processing circuitry is configured to transition to use a third beamforming codebook instead of one or more of the first beamforming codebook or the second beamforming codebook responsive to a change in a signal propagation environment. 
     
     
         20 . The apparatus of  claim 18 , wherein the one or more processors are configured to generate a message to be transmitted to a cellular base station, the message configured to indicate a number of reference signals that are to be transmitted by the cellular base station. 
     
     
         21 . The apparatus of  claim 20 , wherein the processing circuitry is configured to generate the message to be transmitted to multiple cellular base stations. 
     
     
         22 . The apparatus of  claim 18 , wherein the processing circuitry is configured to:
 estimate an effective channel gain for one or more beam pairs; and   generate a message to be transmitted to a cellular base station, the message indicating the estimated effective channel gain.   
     
     
         23 . The apparatus of  claim 18 , wherein the processing circuitry is configured to determine an optimal receive beam from the second beamforming codebook based on measurements of reference signals received from a cellular base station while using the first beamforming codebook. 
     
     
         24 . An apparatus of a user equipment (UE), comprising:
 a data storage device configured to store sample data indicating information measured from a uniformly sampled receive beam space; and   one or more processors configured to:
 estimate one or more parameters of a plurality of receive beams of a codebook based on the stored samples; 
 select a receive beam from a codebook based on the estimated one or more parameters; and 
 receive data from a cellular base station using the selected receive beam. 
   
     
     
         25 . The apparatus of  claim 24 , wherein the one or more processors are configured to generate an acknowledgement (ACK) message to be transmitted to the cellular base station, the ACK message indicating that a quality of samples of the uniformly sampled receive beam space is sufficient. 
     
     
         26 . The apparatus of  claim 24 , wherein the one or more processors are configured to classify some of the samples of the uniformly sampled receive beam space as useful and others of the samples of the uniformly sampled receive beam space as not useful. 
     
     
         27 . The apparatus of  claim 24 , wherein the one or more parameters used to select the receive beam from the codebook are determined by defining a function that depends on the sample data and a potential receive beam, the function chosen to approximate an effective channel gain.